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Transition from the sow to nursery pens is a stressful time for pigs and commonly leads to postweaning anorexia and growth check. This can have negative impacts on pig health, welfare, and lifetime performance. The objective of this study was to test the relationship between enrichment use and feeder use immediately post-weaning on final nursery pig body weight (BW). At arrival, 29 mixed-sex pigs (Camborough 1050 X 337, PIC), 19 to 24d of age, were randomly sorted into 3 pens (~0.29 m2/pig) at the Iowa State University Swine Nutrition Farm. Each pen was equipped with a 4-hole, dry self-feeder measuring 0.6 m long. Each pen had two enrichment devices, consisting of one cotton rope and two biscuits, suspended from the feeder at pig height. Biscuits were replaced daily. Total number of interactions with the enrichment and feeder were collected at the individual pig level. All pigs were continually observed for two 1 h periods (h 1 and the h 6 after biscuit replacement) each day over wk 1 (d 0 – d 6). A pig was considered interacting with enrichment if its snout contacted the rope or enrichment biscuit. A pig was considered interacting with the feeder if 1) its head was over the feeder tray, and 2) its nose down in the feeder. Both enrichment and feeder interactions were considered terminated if the pig ceased active interaction for 3 s or more. Behaviors were summed together by time period and day for each pig. Individual BW were taken at the end of the 42-d nursery study. After the nursery trial was completed, the 29 pigs were allocated to a light BW treatment (n = 14) and a heavy BW treatment (n = 15) using the final average BW (24.22 kg) of the. Pigs with a final BW lighter than the group average were assigned to the light treatment, while pigs with a heavier BW than average were assigned to the heavy treatment. T-tests were conducted for enrichment and feeder interactions by final BW group and the pig was the experimental unit. A P ≤ 0.05 was considered significant. There were no observed differences between final pig body weight treatments and the enrichment and feeder interactions over the first week of nursery (P ≤ 0.87). Numerically, there were more overall enrichment interactions than feeder interactions for both BW treatments over wk 1 (Table 1). In conclusion, this enrichment device was of biological interest to the pigs, but other factors impact feeder usage in the first week and need to be considered in future work. [ABSTRACT FROM AUTHOR]

The yeast extract, derived from 100% natural and pure Saccharomyces cerevisiae, boasts a high digestibility coefficient (> 95%). It is an excellent source of vitamins, minerals, and amino acids, particularly aspartic and glutamic acids, and is noted for its exceptional palatability (Figure 1). This study aimed to assess the impact of dietary yeast extract supplementation on the performance of nursery-phase piglets. Mixed-sex piglets (n = 1,360) were allocated across 18 pens, with 75 animals per pen, and subjected to two treatments (9 replicates each) on a commercial farm in Minas Gerais, Brazil. The treatment groups included a positive control (PC) group, receiving a phase-specific standard diet, and a yeast extract (YE) group, supplemented with 1% yeast extract on top. Initially, all piglets were fed a commercial diet for the first 7 d (from 21 to 27 d old), followed by a farm-specific diet (PC and YE). The YE was administered as a liquid via an oilinjection system at the feed mill. Performance metrics evaluated included body weight gain (BWG) and feed conversion ratio (FCR), with feed intake (FI) being constant due to automated feeding. Data analysis employed ANOVA at a 90% confidence level, with mean differences assessed using the F-test. Piglets in the YE group demonstrated significantly greater BWG from wk 1 post-supplementation, maintaining statistical differences throughout the study (Table 1). The final BWG difference favored the YE group by 1.560 kg (PC = 15.106 kg; YE = 16.666 kg; P-value = 0.05). Notably, animal uniformity within each treatment was superior in the YE group, exhibiting a 49% reduction in variance across the study period compared with the PC group (Figure 2). This improvement in BWG was accompanied by enhanced batch uniformity relative to the PC group. FCR differences were statistically significant from wk 1 of supplementation, concluding with a final FCR of 1.49 for the PC group and 1.39 for the YE group (P-value = 0.02; Table 2). Given the fixed FI across phases, this FCR improvement primarily reflects the observed weight gain differences. These findings indicate that YE supplementation can enhance performance parameters and piglet uniformity in the nursery phase, offering nutritional benefits throughout this critical growth stage. [ABSTRACT FROM AUTHOR]

Thirty five barrows (initial body weight [BW]: 15.1 ± 1.0 kg) were used to determine the effect of partially replacing Gly + Ser with Thr in reduced crude protein (CP) diets on growth performance, protein deposition in carcass and viscera, and skin collagen abundance during the late nursery phase to 25 kg BW. Pigs were individually fed one of five iso-nitrogenous diets (n = 7) for 21 d. The basal diet met estimated essential amino acids (AA) requirements by using all essential AA plus Gly and Ser in free form (CON; 12.1% CP; as-fed, analyzed contents). The remaining four diets were formulated by reducing total Gly and Ser concentrations to 60% or 20% of the CON diet. The N removed with Gly and Ser was replaced with either crystalline Thr or Glu. Total analyzed Thr made up either 1.59% (T1; 12.5% CP) or 2.34% (T2; 12.2% CP) of the Thr-supplemented diets, and total analyzed Glu made up either 3.47% (G1; 12.7% CP) or 4.64% (G2; 12.9% CP) of the Glu-supplemented diets. Pigs were slaughtered on day 21 to determine body composition and skin collagen abundance via bright field microscopy. Overall, average daily gain (ADG) and G:F and final carcass weights were greater for pigs fed diets supplemented with Glu (G1 + G2) vs. those fed diets supplemented with Thr (T1 + T2; P < 0.05, P = 0.060, and P = 0.050 for ADG, G:F, and final carcass weight, respectively); intermediate values were observed for CON. Nitrogen retention in carcass plus viscera and the AA profile of deposited protein in the carcass were not influenced by dietary treatment. Pigs fed the T2 and G2 diets had greater retention of Thr (vs. CON and G2) and Glu (vs. CON and T2) in the viscera protein, respectively (P < 0.05). The apparent utilization efficiency of standardized ileal digestible Thr for protein deposition in carcass plus viscera was less for pigs fed T2 (15.1%) vs. those fed CON (56.7%) or G2 (58.6% ± 2.9%) diets (P < 0.001). Only pigs fed T1 had skin collagen abundance not different from CON; pigs fed G1, G2, and T2 had reduced skin collagen abundance compared with CON and T1 (P < 0.01). Using Glu as an N source when Gly and Ser were reduced to 60% and 20% of CON in reduced CP diets maintained ADG for pigs between 15 and 25 kg BW, whereas supplying Thr as a N source reduced ADG and carcass weight. When dietary Gly and Ser were supplied at 60% of CON, only Thr supplementation rescued skin collagen abundance. Therefore, supplemental Thr at excess levels is not sufficient to replace N from Gly and Ser in reduced CP diets fed to late nursery pigs, despite supporting skin collagen abundance as a secondary indicator of Gly status. [ABSTRACT FROM AUTHOR]

Previous work by our group has found that housing pigs with a ramp in the pen during only the nursery period increased the speed of trailer ramp loading at marketing. However, the presence of the ramp may also alter pig behavior during the nursery period. The objective of this study was to evaluate whether ramp exposure affects pig behavior during the nursery period. We predicted that pigs exposed to a ramp would exhibit reduced aggressive behaviors, but similar eating, drinking, and postural behaviors during the nursery period compared with pigs not given access to a ramp. Two hundred four pigs (17 to 21 d of age) were placed in 8 pens (n = 24 to 27 pigs per pen) that were allocated to 1 of 2 treatments: 1) RAMP (n = 4 pens; standard commercial pen equipped with a ramp), or 2) CONTROL (n = 4 pens; standard commercial pen without a ramp). One day after placement (D1) and again 18 days later (D2), incidences of eating, drinking, aggressive, and postural (standing, lying) behaviors within each pen were collected for a period of 60 min at 0800, 1200, and 1600 h using a 5-min instantaneous scan sampling strategy. Data were analyzed using the GLIMMIX procedure in SAS with treatment, experimental day (D1, D2), hour (0800, 1200, 1600 h), and all 2-way interactions as fixed effects. Pen was included as a random effect. No treatment differences (P > 0.55) were detected for the evaluated behaviors. Greater incidences of eating were observed on D2 than on D1 (P < 0.0001). There were fewer pigs drinking at 1600 h on D1 than all other time points (P < 0.04) except for 1200 h on D1 (P = 0.64). There were also fewer pigs drinking at 1200 h on D1 than at 1600 h on D2 (P = 0.047). A greater incidence of aggressive behavior was observed at 0800 h on D1 compared with all other time points (P < 0.01), with no other differences observed (P > 0.40). Standing behavior was greater at 0800 h on D1 compared with all other time points (P < 0.02) except for 1600 h on D2 (P = 0.42). There were also fewer incidences of standing at 1600 h on D1 than 0800 or 1200 h on D2 (P = 0.01 and 0.03, respectively). Finally, there were more lying incidences at 1600 h on D1 than all other time points (P < 0.02) except for 1200 h on D1 (P = 0.81). Taken together, eating, drinking, aggressive, and postural behaviors changed by experimental day and hour after weaning. However, pig behavior was not altered due to ramp exposure. [ABSTRACT FROM AUTHOR]

Two experiments were conducted to understand the growth and health benefits of including treated wheat straw in weanling pig diets. The first experiment evaluated feeding treated versus untreated wheat straw on young pig growth performance and localized immunological markers. One hundred and ninety-two (PIC 359 x Yorkshire) pigs were weaned at 26.8 ± 1.1 d old (8.3 ± 1.1 kg) and randomly allotted to 24 pens with 8 pigs per pen. Three dietary treatments were fed over a 28-d period, control (CON), control plus 5% untreated wheat straw (UWS), and control plus 5% treated wheat straw (TWS). Diets were formulated to meet or exceed all nutrient requirements of NRC, 2012. Growth performance data was recorded on a weekly basis. One pig per pen (equal number of males and females) was randomly selected for sacrifice and sample collection on d 28. The second experiment evaluated the impact of 5% dietary TWS on the local and systemic health of nursery pigs experiencing a vaccination-induced immune challenge. Twenty barrows (PIC 800 x Yorkshire) were weaned at 27.7 ± 0.75 d (8.6 ± 1.2 kg) and assigned to four pens, with 5 pigs per pen. A heavy and light-weight pen for each treatment (CON and TWS) resulted. All pigs were sacrificed for sample collection on d 42. In both experiments, before euthanasia, blood was collected to assess plasma immunoglobulin A (IgA) and intestinal fatty acid binding protein (iFABP) concentration. Upon sacrifice, segments of the distal ileum and ascending colon were removed to collect mucosal scrapings for the analysis of localized immunological markers interleukin (IL) 6, IL-10, IL-12, and tumor necrosis factor-alpha (TNF-α). In experiment one, overall ADG and ADFI were similar among treatments. Gain-to-feed ratio of TWS pigs was greater (P < 0.05) than that of UWS pigs and tended to be greater (P = 0.07) than that of CON pigs (0.70, 0.67, and 0.68, respectively; SEM = 0.01). Both straw treatments decreased the expression of ileal and colonic mucosa IL-6, in addition with less expression of ileal IL-12. Plasma IgA concentrations in UWS pigs were greater than those in CON and TWS pigs (P < 0.05). In experiment two, TWS pigs had greater gene expression of colonic TNF-α and IL-6 (P < 0.05). Ileal gene or protein expression of markers did not differ, nor did amounts of plasma IgA or iFABP. Overall, feeding 5% treated wheat straw in the nursery pig diet does not negatively impact growth and results in increased feed efficiency. Nursery diets with 5% treated wheat straw can impact the expression of immune markers in the gut, but the question of how this is related to performance and overall health needs further elucidation. [ABSTRACT FROM AUTHOR]

Current recommended room temperatures for newly weaned pigs are based on historical research carried out several years ago. Since that time, major changes have occurred in the genotype of the pigs and in the management and the housing environment. This study was carried out to determine if a temperature regimen based on the choice of temperature of the pigs would improve post-weaning performance of pigs of different weaning weights. This study was carried out over the first 4 weeks after weaning (21 ± 1 d) using a split-plot design with 2 treatments: 1) Room Temperature Regimen (RT; main plot; Preferred vs. Control); 2) Weaning Weight (WW; subplot; Light vs. Heavy). Room temperatures for the Preferred treatment were 32, 32, 30, and 28℃ for wk 1, 2, 3, and 4 of the study, respectively. Room temperatures for the Control treatment (based on current recommendations) were 28, 26, 24, and 22℃ for week 1, 2, 3, and 4 of the study, respectively. The WW treatments were based on the lightest and heaviest pigs, respectively, from each litter. Four identical rooms of a wean-tofinish facility were used (2 rooms/RT treatment); 256 newly weaned pigs were housed in mixed-sex pens of 8 (16 pens/RT treatment) at a floor space of 0.78 m2/pig. Growth performance (ADG, ADFI, G:F) and mortality were measured over the 4-wk study period. The average start and end weight was 4.6 ± 0.32 kg and 12.7 ± 0.89 kg, respectively, for the Light WW treatment and was 6.4 ± 0.40 kg and 15.8 ± 1.47 kg, respectively for the Heavy WW treatment. There were no interactions (P > 0.05) between RT and WW for growth performance measures. There was no effect (P > 0.05) of RT on overall growth performance. Light WW pigs had less (P < 0.05) overall ADG (0.29 vs. 0.34 kg; SEM 0.009) and ADFI (0.40 vs. 0.46 kg; SEM 0.010) but similar G:F (0.733 vs. 0.739 kg; SEM 0.0115) compared with Heavy WW pigs. There was an interaction (P < 0.05) between the RT and WW treatments for overall mortality. There was no effect (P > 0.05) of RT for Heavy WW pigs (3.1 vs. 1.6 % for the Preferred and Control treatments, respectively; SEM = 1.89); however, mortality was less (P < 0.05) for Light pigs on the Preferred than on the Control treatment (1.6 vs. 7.8 %, respectively; SEM 1.89). In conclusion, the Preferred RT treatment did not impact growth performance in the first 4 weeks after weaning but reduced mortality of pigs of light, but not heavy weaning weight. This finding warrants verification under commercial conditions. [ABSTRACT FROM AUTHOR]

Changes in weaning age and diet complexity can impact pig growth post-weaning. Weanling gilts and barrows [n = 432 Topigs Duroc X (US York X Landrace)] from the same farrowing group were utilized for a 30 or 35 day growth trial to compare early (EW) versus late weaning (LW) and high or low levels of specialty proteins in nursery diets. Pigs (n = 216) were EW (18 or 19 d, average Age = 18.4 days, average BW = 5.96 kg) and 216 pigs were LW 5 days later (24, 25 or 26 d, average Age = 24.6 d, average BW = 7.50 kg). At weaning pigs were blocked by weaning age, BW, sex and litter, and randomly allotted to 48 pens with 9 pigs/pen. Pigs at each weaning age were fed a High Complexity (HC) or a Low Complexity (LC) diet. The trial was conducted as a 2X2 factorial design: 1) EW+HC; 2) EW+LC; 3) LW+HC; 4) LW+LC. Pigs and feeders were weighed on d 0, 7, 14, 21, 28, and 35 for EW, and on d 0, 7, 14, 21, 28, and 30 for LW. The LW pigs had improved ADG and ADFI from days 0-7, 7-14, 14-21, and the final week of the nursery (P < 0.05). There were no differences in ADG and ADFI from days 21-28 (P > 0.05) between weaning ages. G:F decreased for LW pigs from days 21-28 (P < 0.01) compared with EW pigs; however, for the overall nursery trial LW pigs had increased G:F (P = 0.01). The LW pigs had increased overall nursery ADG vs EW pigs (452.5 g/d vs 400 g/d; P < 0.01). End of nursery BW was greater for LW vs EW pigs (21.70 kg vs 20.74 kg; P = 0.001). When comparing pigs of similar BW at weaning, LW pigs were lighter at end of nursery (20.13 kg vs. 21.66 kg; P < 0.01) but were more feed efficient (P < 0.01) than EW pigs. There was a BW block by weaning age interaction, EW heavy pigs had less ADG compared with LW heavy pigs; however, when comparing light weight pigs, the EW light pigs had improved ADG compared with LW light weight pigs (P = 0.017). The EW pigs were lighter at market (approximately day 146 of age) compared with LW pigs (120.78 vs 124.16 kg; P = 0.014). An interaction between weaning age, nursery diet, and sex (P < 0.07) was observed for market weight, EW barrows fed LC diets were lighter at market (120.77 kg) than EW barrows fed HC diets (126.54 kg). Whereas for LW barrows fed LC had greater market weights (130.04 kg) than LW barrows fed HC diets (127.59 kg). A similar, but nonsignificant pattern was observed for gilts. Weaning age and feeding pigs the correct diet for their age in the nursery can have a lifelong effect on the pig. [ABSTRACT FROM AUTHOR]

An experiment was conducted to evaluate the effect of dietary medium-chain fatty acid (MCFA) addition on nursery pig growth performance, fecal microbial composition, and mitigation of porcine epidemic diarrhea virus (PEDV) following storage. A total of 360 pigs (DNA 400 × 200, Columbus, NE; initially 6.7 ± 0.07 kg) were randomized to pens (5 pigs per pen) on the day of weaning (approximately 20 d of age), allowed a 6-d acclimation, blocked by BW, and randomized to dietary treatment (9 pens per treatment). All MCFA (Sigma–Aldrich, St. Louis, MO) were guaranteed ≥98% purity, including hexanoic (C6:0), octanoic (C8:0), and decanoic (C10:0) acids. Treatment diets were formulated in 2 phases (7 to 11 and 11 to 23 kg BW) and formulated to meet or exceed NRC requirement estimates. Treatments (n = 8) were a dose response including 0%, 0.25%, 0.5%, 1.0%, and 1.5% added MCFA blend (1:1:1 ratio C6:0, C8:0, and C10:0), as well as treatments with individual additions of 0.5% C6:0, C8:0, or C10:0. Fecal samples were collected from pigs fed control and 1.5% MCFA blend diets on days 0 and 14 and analyzed using 16s rDNA sequencing. Following feed manufacture, feed was stored in bags at barn temperature and humidity for 40 d before laboratory inoculation with PEDV. Subsamples of retained feed were inoculated with PEDV to achieve a titer of 104 TCID50/g and separate sample bottles were analyzed on 0 and 3 d post-inoculation (dpi). Overall, ADG and ADFI were increased (linear, P ≤ 0.010) and feed efficiency (G:F) improved (linear, P = 0.004) with increasing MCFA blend. Pigs fed 0.5% C8:0 had greater (P = 0.038) ADG compared with pigs fed the control diet, and G:F was improved (P ≤ 0.024) when pigs were fed 0.5% C6:0, 0.5% C8:0, or 0.5% C10:0 compared with control. An inclusion level × day interaction was observed (quadratic, P = 0.023), where PEDV Ct values increased (quadratic, P = 0.001) on 0 dpi with increasing levels of MCFA blend inclusion and also increased on 3 dpi (linear, P < 0.001). Fecal microbial diversity and composition were similar between control and 1.5% MCFA blend. In summary, the use of MCFA in nursery pig diets improves growth performance, provides residual mitigation activity against PEDV, and does not significantly alter fecal microbial composition. [ABSTRACT FROM AUTHOR]

Antibiotic use has been limited in U.S. swine production. Therefore, the objective was to determine whether supplementing l -glutamine at cost-effective levels can replace dietary antibiotics to improve piglet welfare and productivity following weaning and transport. Based on previous research, we hypothesized that withholding dietary antibiotics would negatively affect pigs while diet supplementation with 0.20% l -glutamine (GLN) would have similar effects on pig performance and health as antibiotics. Mixed sex piglets (N = 480; 5.62 ± 0.06 kg BW) were weaned (18.4 ± 0.2 d of age) and transported for 12 h in central Indiana, for 2 replicates, during the summer of 2016 and the spring of 2017. Pigs were blocked by BW and allotted to 1 of 3 dietary treatments (n = 10 pens/dietary treatment/replicate [8 pigs/pen]); antibiotics (A ; chlortetracycline [441 ppm] + tiamulin [38.6 ppm]), no antibiotics (NA), or GLN fed for 14 d. On days 15 to 34, pigs were provided common antibiotic-free diets in 2 phases. Data were analyzed using PROC MIXED in SAS 9.4. Day 14 BW and days 0 to 14 ADG were greater (P = 0.01) for A (5.6% and 18.5%, respectively) and GLN pigs (3.8% and 11.4%, respectively) compared with NA pigs, with no differences between A and GLN pigs. Days 0 to 14 ADFI increased for A (P < 0.04; 9.3%) compared with NA pigs; however, no differences were detected when comparing GLN with A and NA pigs. Once dietary treatments ceased, no differences (P > 0.05) in productivity between dietary treatments were detected. On day 13, plasma tumor necrosis factor alpha (TNF-α) was reduced (P = 0.02) in A (36.7 ± 6.9 pg/mL) and GLN pigs (40.9 ± 6.9 pg/mL) vs. NA pigs (63.2 ± 6.9 pg/mL). Aggressive behavior tended to be reduced overall (P = 0.09; 26.4%) in GLN compared with A pigs, but no differences were observed between A and GLN vs. NA pigs. Huddling, active, and eating/drinking behaviors were increased overall (P < 0.02; 179%, 37%, and 29%, respectively) in the spring replicate compared with the summer replicate. When hot carcass weight (HCW) was used as a covariate, loin depth and lean percentage were increased (P = 0.01; 4.0% and 1.1%, respectively) during the spring replicate compared with the summer replicate. In conclusion, GLN supplementation improved pig performance and health after weaning and transport similarly to A across replicates; however, the positive effects of A and GLN were diminished when dietary treatments ceased. [ABSTRACT FROM AUTHOR]

Antibiotic use has been limited in U.S. swine production. Therefore, the objective was to determine whether supplementing l -glutamine at cost-effective levels can replace dietary antibiotics to improve piglet welfare and productivity following weaning and transport. Based on previous research, we hypothesized that withholding dietary antibiotics would negatively affect pigs while diet supplementation with 0.20% l -glutamine (GLN) would have similar effects on pig performance and health as antibiotics. Mixed sex piglets (N = 480; 5.62 ± 0.06 kg BW) were weaned (18.4 ± 0.2 d of age) and transported for 12 h in central Indiana, for 2 replicates, during the summer of 2016 and the spring of 2017. Pigs were blocked by BW and allotted to 1 of 3 dietary treatments (n = 10 pens/dietary treatment/replicate [8 pigs/pen]); antibiotics (A ; chlortetracycline [441 ppm] + tiamulin [38.6 ppm]), no antibiotics (NA), or GLN fed for 14 d. On days 15 to 34, pigs were provided common antibiotic-free diets in 2 phases. Data were analyzed using PROC MIXED in SAS 9.4. Day 14 BW and days 0 to 14 ADG were greater (P = 0.01) for A (5.6% and 18.5%, respectively) and GLN pigs (3.8% and 11.4%, respectively) compared with NA pigs, with no differences between A and GLN pigs. Days 0 to 14 ADFI increased for A (P < 0.04; 9.3%) compared with NA pigs; however, no differences were detected when comparing GLN with A and NA pigs. Once dietary treatments ceased, no differences (P > 0.05) in productivity between dietary treatments were detected. On day 13, plasma tumor necrosis factor alpha (TNF-α) was reduced (P = 0.02) in A (36.7 ± 6.9 pg/mL) and GLN pigs (40.9 ± 6.9 pg/mL) vs. NA pigs (63.2 ± 6.9 pg/mL). Aggressive behavior tended to be reduced overall (P = 0.09; 26.4%) in GLN compared with A pigs, but no differences were observed between A and GLN vs. NA pigs. Huddling, active, and eating/drinking behaviors were increased overall (P < 0.02; 179%, 37%, and 29%, respectively) in the spring replicate compared with the summer replicate. When hot carcass weight (HCW) was used as a covariate, loin depth and lean percentage were increased (P = 0.01; 4.0% and 1.1%, respectively) during the spring replicate compared with the summer replicate. In conclusion, GLN supplementation improved pig performance and health after weaning and transport similarly to A across replicates; however, the positive effects of A and GLN were diminished when dietary treatments ceased. [ABSTRACT FROM AUTHOR]

An experiment was conducted to determine the interactive effects of standardized ileal digestible (SID) lysine, dietary fiber, and amino acid ratios on growth performance of nursery pigs. A total of 4,320 pigs (initial BW = 7.8 kg), placed in pens of 36 mixed sex pigs, were used in a 43-d trial. Treatments were arranged in a 2 × 2 × 2 factorial structure with two levels of SID Lys (1.15 or 1.38%), two levels of dietary fiber [control or high fiber (5% sugar beet pulp + 3.75% soy hulls)], and two amino acid ratio profiles [control (65% SID Thr:Lys, 58% SID Met+Cys:Lys, 67% SID Val:Lys, 55% SID Ile:Lys, and 18.5% SID Trp:Lys) or AA+ (5 percentage points greater than control ratios)] with 15 replicates per treatment. The experimental diets were fed from d 0 to 25 and a common corn-soybean meal-based diet was fed from d 25 to 43. Pigs were weighed on d 0, 25, and 43 to calculate ADG, ADFI, and G:F. Data were analyzed with the MIXED procedure in SAS. From d 0 to 25, there was a fiber × amino acid ratio interaction (P = 0.008) for ADFI, where pigs fed the high fiber diet had similar ADFI, regardless of AA ratios, but those fed control levels of fiber had reduced ADFI when fed AA+ ratios (Table 1). Similar interactions were also observed (P < 0.05) for overall (d 0 to 43) ADG, ADFI, and final BW. There were no other significant interactions (P > 0.05). As for main effects, pigs fed low Lys had reduced (P < 0.05) ADG, ADFI, and G:F. Feeding high fiber diets reduced (P < 0.05) G:F but did not impact (P > 0.05) ADG or ADFI. Pigs fed AA+ ratios had improved (P < 0.05) G:F but no evidence for differences (P > 0.05) for ADG or G:F was observed. [ABSTRACT FROM AUTHOR]

A total of 1,156 PIC 800-sired pigs (12.4 kg BW) were used in a 27-day experiment to estimate the SID lysine requirement of pigs ranging from 12.4 to 31.3 kg BW. Forty-eight pens of mixed sex pigs were used. Pens were blocked by location within the barn, with barrow and gilt numbers in pens kept consistent within block. Pens were allotted to one of five dietary treatments in a randomized design with 9 to 10 replicate pens (10 pens for treatments 1, 3, 5 and 9 pens for treatments 2, 4) per treatment. Dietary SID lysine concentrations evaluated were 1.12, 1.19, 1.26, 1.33, and 1.40%. Diets were corn-soybean meal-based and formulated to equal NE concentrations across treatment. Data were analyzed using a general linear model. Orthogonal contrasts with coefficients for equally spaced treatments were used to analyze for linear and quadratic effects. For significant quadratic effects, breakpoint analysis was conducted (two slope regression or quadratic broken line analysis) using nonlinear regression analysis to estimate for SID lysine requirement. A linear (P < 0.05) response was observed for BW to increase as SID lysine level in the diet increased. Increasing SID lysine increased average daily gain (ADG) quadratically (P = 0.05) with a plateau observed above 1.357% SID Lys. Additionally, increased SID lysine yielded a quadratic effect on G:F (P < 0.05) with a plateau above 1.327% SID lysine. There was a quadratic response (P < 0.05) observed for cost of gain (COG), with no benefit to COG when feeding above 1.201% SID lysine. However, there was a linear response (P < 0.05) observed for return over feed cost (ROFC) as SID lysine increased due to increased BW. There was no effect of SID lysine level fed on feed intake or mortality and morbidity. These data indicate that the estimated SID lysine requirement for PIC 800-sired pigs ranging from 12.4 to 31.3 kg to be 1.327 and 1.357 for optimal feed efficiency and ADG, respectively. [ABSTRACT FROM AUTHOR]

An experiment was conducted to evaluate the interactive effects of soybean meal (SBM) concentration and functional amino acids (FAA) threonine, tryptophan, and methionine supplementation above the requirements on the growth performance of nursery pigs. A total of 2,592 pigs (initial BW = 6.1 kg), placed in pens of 36 mixed-sex pigs, were used in a 33-d trial. Pens of pigs were allotted to 1 of 6 dietary treatments arranged as a 2 × 3 factorial with two levels of SBM (25 or 31%) and three FAA regimens (Low, Medium, and High) with 12 replicates per treatment. Amino acid ratios were: 58.5% SID Thr:Lys, 55% SID Met+Cys:Lys, and 16.5% SID Trp:Lys for the Low treatment; 65% SID Thr:Lys, 58% SID Met+Cys:Lys, and 18.5% SID Trp:Lys for the Medium treatment; and 71% SID Thr:Lys, 66% SID Met+Cys:Lys, and 23.5% SID Trp:Lys for the High treatment. Diets were fed in two phases: phase 1 from d 0 to 19 in pellet form and phase 2 from d 19 to 33 in mash form. Pigs were weighed on d 0, 19, and 33 to calculate ADG, ADFI and G:F. Data were analyzed with the MIXED procedure in SAS (Table 1). From d 0 to 19, there was no evidence (P > 0.10) for interactive effects. Pigs fed the Low FAA ratios had the poorest G:F (P = 0.004). From d 19 to 33 and overall (d 0 to 33), there was an interaction (P = 0.031) for G:F, where pigs fed 25% SBM had improved G:F with Medium or High FAA whereas those fed 31% SBM had improved G:F only with High FAA. There was no evidence (P > 0.10) for differences on ADG or ADFI throughout the study. In conclusion, our findings suggest a minor positive effect of FAA supplementation, with no effects of SBM on performance of weaned pigs. [ABSTRACT FROM AUTHOR]

An experiment was conducted to test the hypothesis that supplementing diets with a blend of medium chain fatty acids (MCFA) and a phytogenic feed additive (Fresta Protect, Delacon, Linz, Austria), together or separately, would improve growth performance and stool quality of nursery pigs challenged with Escherichia coli (ETEC). A total of 200 pigs [5.52 ± 0.17 kg body weight (BW)] were weaned at 17 to 19 days of age, allotted to 40 pens (5 pigs/pen), and allowed to acclimate for 2 days before initiation of dietary treatments. Pens were blocked by BW and randomly assigned to 1 of 5 treatments: negative control (NC), NC + 55 mg/kg carbadox (Positive control; PC), NC + 1.0% MCFA, NC + 0.1% phytogenic, or NC + 1.0% MCFA and 0.1% phytogenic. All pigs were administered an oral gavage of 5 mL ETEC (blend of K88+ and F18+) with a final titer of 1010 CFU/pig on day 5 and 6. Body weights were recorded on days 0, 4, 11, and 18, whereas feed intake was recorded for the overall trial (day 0 - 18). Fecal scores were assessed daily on an ordered likert scale to determine the joint probability of more normal stool quality. Data were analyzed using the lme4 package of R 4.1.2, and the statistical models included the fixed effect of treatment and random effect of BW block. Growth performance data were assumed to be normally distributed, whereas mortality and stool quality were analyzed using generalized linear mixed models specifying binomial and multinomial distributions, respectively. Contrasts were used to test for effects of dietary additive (carbadox, MCFA, phytogenic, or MCFA and phytogenic) compared with NC (Table 1). Results indicated postchallenge BW, post-challenge and overall average daily gain (ADG), and overall gain:feed (G:F) were greater (P < 0.05) for PC than for NC. In the pre-challenge phase, dietary inclusion of MCFA reduced (P < 0.05) final BW and ADG compared with NC, but overall G:F was greater (P < 0.05) than NC when the MCFA blend was fed. Inclusion of the phytogenic increased (P < 0.05) ADG in the post-challenge period and G:F in the overall trial compared with NC. The combination of MCFA blend and phytogenic resulted in increased (P < 0.05) post-challenge final BW, post-challenge ADG, and overall ADG compared with NC. All treatments, except MCFA blend, tended (P < 0.10) to reduce mortality compared with NC. The PC, MCFA blend, and combination treatments resulted in a greater (P < 0.05) probability of normal stool quality than NC. In conclusion, supplementation of the phytogenic and the combination of MCFA with phytogenic improved growth performance and tended to reduce mortality of nursery pigs under ETEC challenge. Furthermore, the combination improved stool quality. [ABSTRACT FROM AUTHOR]

An experiment was conducted to determine the interactive effects of soy hulls (SH) and sugar beet pulp (SBP) on growth performance of nursery pigs. A total of 2,448 mixed sex pigs (initial BW = 6.3 kg), placed in pens of 36 pigs each, were used in a 40-d trial. Treatments were arranged in a 2 × 3 factorial with two levels of SBP (0 or 5%) and 3 levels of SH (0, 3.75, or 7.5%) with 11 replicates per treatment. Corn and a fermented soybean meal product (ME-Pro, Prairie AquaTech, Brookings, SD) were replaced by the fiber sources to achieve the desired fiber concentration, whereas soybean meal inclusion rate was held constant across treatments. Diets were not balanced for net energy. Experimental diets were fed from d 0 to 18 and a common corn-soybean meal-based diet was fed from d 18 to 40. Pigs were weighed on d 0, 18, and 40 to calculate ADG, ADFI, and G:F (Table 1). Data were analyzed with the MIXED procedure in SAS. From d 0 to 18, there was a SH × SBP interaction for ADG (P = 0.016) and ADFI (P = 0.023). Pigs fed diets with the highest inclusion of SH without SBP had increased ADG and ADFI; however, pigs fed diets containing SBP had improved performance up to 3.75% SH inclusion, and decreased ADG and ADFI with the highest SH inclusion. From d 18 to 40 and overall (d 0 to 40), there was an interaction (P = 0.007) for G:F, where pigs fed diets containing 3.75% SH without SBP had improved G:F, while pigs fed diets with 3.75% SH containing SBP had worsened G:F. In summary, these results suggest that both fiber sources can be safely fed to nursery pigs, although the interactive effects must be considered when determining inclusion rates. [ABSTRACT FROM AUTHOR]

Two groups of 240 pigs (PIC 337 X 1050, PIC Genus, Hendersonville, TN) with initial body weight (BW) 13.20 ± 3.05 kg were used to investigate interactions between the branched-chain amino acids (BCAA). At weaning, pigs were placed into 40 pens with three barrows and three gilts per pen and fed a common diet for 3 weeks. On day 21 post-weaning, pens were randomly assigned to 1 of 15 dietary treatments arranged in a rotatable central composite design. Experimental diets were formulated to various levels of standardized ileal digestible (SID) leucine, isoleucine, and valine by replacing corn starch and glycine with L-leucine, L-isoleucine, and L-valine in the base diet. Levels of BCAA were expressed as ratios to SID lysine and ranged from 98 to 180 for Leu, 46 to 64 for Ile, and 51 to 78 for Val. Diets were formulated to be sublimiting in lysine at 1.19% SID Lys and exceed all other essential amino acid requirements. Additionally, diets were formulated to be isocaloric and isonitrogenous and met or exceeded NRC (2012) vitamin and mineral requirements. Pen weights and feed intake were measured for the 21-day experiment to calculate daily gain (ADG), average daily feed intake (ADFI), and feed efficiency (G:F). Data were fit as a second-order response surface model according to the central composite design in R version 4.2.1 (R Core Team, 2022). The model included linear and quadratic effects of Leu, Ile, and Val, and their cross-products. Pen was the experimental unit, and variables were considered significant at P = 0.10. Valine linearly and quadratically impacted ADG and G:F, regardless of Leu and Ile levels. There was an interaction between Leu and Ile for ADG (P = 0.079) and G:F (P = 0.031), where, at increasing levels of Leu, decreasing Ile improved ADG and G:F. Conversely, ADG and G:F decreased as both Leu and Ile increased. Isoleucine did not impact ADFI (P = 0.458); however, there was an interaction between Leu and Val (P = 0.088), where Leu negatively impacted ADFI at low levels of Val, but did not influence ADFI at greater levels of Val. In conclusion, the response of nursery pig ADG and G:F to Val is independent of Leu and Ile levels, while ADG and G:F are reduced at greater levels of Leu and Ile, which is resolved as either Leu or Ile are reduced. Furthermore, at deficient levels of Val, ADFI is negatively impacted by increased Leu; however, the negative impacts of increasing Leu on ADFI are negated when Val is adequate or above requirement. This experiment emphasizes the complexity of amino acid metabolism in nursery pigs and the importance of understanding potential interactions among amino acids when conducting research. [ABSTRACT FROM AUTHOR]

An experiment was conducted to determine the interactive effects of wheat middlings (WM) and sugar beet pulp (SBP), on growth performance of nursery pigs. A total of 2,393 pigs (initial BW = 7.4 kg), placed in pens with 33 to 35 pigs each, were used in a 42-d trial. Treatments were arranged in a 2 × 3 factorial structure with two levels of WM (0 or 15%) and three levels of SBP (0, 2.5, or 5%) with 12 replicates per treatment. Corn and a fermented soybean meal product (ME-Pro, Prairie AquaTech, Brookings, SD) were replaced by the fiber sources to achieve the desired levels, whereas soybean meal inclusion rate was held constant across treatments. Diets were not balanced for net energy. The experimental diets were fed from d 0 to 21 and a common corn-soybean meal-based diet was fed from d 21 to 42. Pigs were weighed on d 0, 21, and 42 to calculate ADG, ADFI, and G:F (Table 1). Data were analyzed with the MIXED procedure in SAS. There was no evidence (P > 0.10) for WM × SBP interactive effects. From d 0 to 21, pigs fed WM had poorer (P = 0.040) ADG, ADFI, and G:F. Feeding up to 5% SBP did not affect (P > 0.10) growth performance. From d 21 to 42, pigs previously fed WM had improved (P = 0.012) G:F and those previously fed SBP had decreased (P, linear = 0.032) G:F. Overall (d 0 to 42), pigs fed WM had lower (P = 0.048) ADG and G:F and those fed SBP had decreased (P, linear = 0.012) G:F. In conclusion, there were no interactive effects between WM and SBP. Pigs fed 15% WM had decreased performance and a minor impact was observed by feeding up to 5% SBP. [ABSTRACT FROM AUTHOR]

The objective of this study was to determine the effectiveness of a nonpenetrating captive bolt, Zephyr-E, for euthanasia of suckling and weaned pigs from 3 to 9 kg (5-49 d of age) using signs of insensibility and death as well as postmortem assessment of traumatic brain injury (TBI). The Zephyr-E was used by 15 stock people to euthanize 150 compromised pigs from 4 farrowing and nursery units from commercial farms and 2 research stations. Brainstem reflexes, convulsions, and heartbeat were used to assess insensibility, time of brain death, and cardiac arrest following Zephyr-E application. Skull fracture displacement (FD) was quantified from computed tomography (CT) scans (n = 24), macroscopic scoring was used to assess brain hemorrhage and skull fracture severity (n = 150), and microscopic scoring was used to assess subdural hemorrhage (SDH) and parenchymal hemorrhage within specific brain regions that are responsible for consciousness and vital function (n = 32). The Zephyr-E caused immediate, sustained insensibility until death in 98.6% of pigs. On average, clonic convulsions (CC) ceased in 82.2 s (±3.4 SE), brain death was achieved in 144.9 s (±5.4 SE), and cardiac arrest occurred in 226.5 s (±8.7 SE). Time of brain death and cardiac arrest differed significantly among stock people (P = 0.0225 and P = 0.0369). Age was positively related to the duration of CC (P = 0.0092), time of brain death (P = 0.0025), and cardiac arrest (P = 0.0068) with shorter durations seen in younger pigs. Average FD was 8.3 mm (±1.0 SE). Macroscopic scores were significantly differnt among weight classes for subcutaneous (P = 0.0402) and subdural-ventral (P = 0.0037) hemorrhage with the lowest severity hemorrhage found in the 9-kg weight category. Microscopic scores differed among brain sections (P = 0.0070) for SDH with lower scores found in the brainstem compared to the cerebral cortex and midbrain. Parenchymal hemorrhage differed among brain sections (P = 0.0052) and weight categories (P = 0.0128) with the lowest scores in the midbrain and brainstem and the 7- and 9-kg weight categories. The Zephyr-E was highly effective for the euthanasia of pigs up to 9 kg (49 d) based on immediate insensibility sustained until death. Postmortem results confirmed that severe skull fracture and widespread brain hemorrhage were caused by the Zephyr-E nonpenetrating captive bolt. [ABSTRACT FROM AUTHOR]

Lysozyme is a 1,4-(3-N-acetylmuramidase that has antimicrobial properties. The objective of this study was to determine the effect of lysozyme and antibiotics on growth performance and immune response during an indirect immune challenge. Two replicates of 600 pigs each were weaned from the sow at 26 d of age, blocked by litter and sex, and then randomly assigned to 1 of 24 pens in either a nursery room that had been fully disinfected or a nursery room left unclean since the previous group of pigs. Within a room, pigs were randomly assigned to either control diets (2 phase nursery regime), control diets + antibiotics (chlortetracycline/tiamulin hydrogen fumarate), or control diets + lysozyme (100 mg/kg diet). Pig weights and feed disappearance were measured and blood was collected on d 0, 14, and 28 of treatment. A group of 20 pigs were killed at 24 d of age for initial body composition analysis and 10 pigs of median weight were killed per diet room combination for body composition analysis after 28 d of treatment. Control + antibiotics and control + lysozyme-fed pigs grew at a faster rate for the 28-d study compared to control pigs (318 ± 14,320 ± 15 vs. 288 ± 15 g/d, respectively; P < 0.05), regardless of nursery environment (P > 0.05). The indirect immune challenge did not alter growth performance from d 0 to 14 of treatment but decreased ADG from d 14 to 28 of the study (415 ± 15 vs. 445 ± 13 g/d; P < 0.05). Feed intake was not altered by the nursery environment (P > 0.61) or dietary treatments (P > 0.10), but feed efficiency was worsened by the indirect immune challenge (P < 0.05) and improved by both control + antibiotics and control + lysozyme diets (P < 0.01). The immune challenge did not alter nutrient accretion (P > 0.25), but both control + antibiotics and control + lysozyme pigs had decreased accretion of whole-body lip-id (P < 0.01) and increased accretion of protein (P < 0.09). Blood levels of tumor necrosis factor-a (TNF-a; P < 0.01), haptoglobin (P < 0.09), and C-reactive protein (CRP; P < 0.01) were higher due to the indirect immune challenge compared to pigs reared in the clean nursery (P < 0.05). In addition, pigs consuming antibiotics or lysozyme had lower TNF-a, haptoglobin, and CRP compared to control pigs, regardless of nursery environment (P < 0.04). Thus, lysozyme is a suitable alternative to antibiotics in swine nursery diets, and lysozyme ameliorates the effects of a chronic indirect immune challenge. [ABSTRACT FROM AUTHOR]

An experiment was conducted to examine the effect of the nursery feeding program on subsequent growth performance, carcass quality, meat quality, and physical and chemical body composition of growing-finishing pigs. Four dietary treatments were used in a 2x2 factorial arrangement of treatments based on diet complexity (Complex vs. Simple) and infeed antibiotics (2,730 [+AB] vs. 0 [-AB] mg of chlortetracycline /kg],A total of 552 pigs, in 5 blocks, were weaned at 21 ± 2 d of age with an initial BW of 7.03 ± 0.07 kg. Each experimental block had 3 pens per treatment, with 8 pigs per pen in blocks 1 and 2, and 10 pigs per pen in the remaining 3 blocks. Nursery diets were fed in a 3-phase feeding program (Phase I, II, and III diets fed for 1, 2, and 3 wk, respectively). All pigs were fed common grower-finisher diets thereafter. Six pigs per treatment were slaughtered for chemical body composition analysis at wk 2, 8, 12, and 17 postweaning. An additional 11 pigs per treatment were slaughtered at wk 17 postweaning (approximately 115 kg BW or market weight) for analysis of carcass characteristics, chemical and physical body composition, and meat quality. During the nursery phase, ADG was lower (P < 0.05) for pigs fed the Simple diet than those fed the Complex diet (491 vs. 528 g/d). Antibiotic usage improved (P < 0.05) ADG in Phases II (408 vs. 438 g/d) and III (689 vs. 720 g/d). In Phase I and II, G:F was lower {P < 0.05) for pigs fed the Simple diet than those fed the Complex diet (0.46 vs. 0.58 and 0.75 vs. 0.78 in Phases I and II, respectively). During the grower phase, pigs previously fed -AB diets grew faster than pigs fed +AB diets (P < 0.05; 1,009 vs. 971 g/d). There were no treatment effects on overall ADG or G:F from weaning to finishing. Nursery feeding program did not affect carcass quality characteristics. However, pigs previously fed +AB diets tended (P = 0.07) to have increased LM depth. Nursery feeding program had no effect on objective or subjective meat quality measures, chemical body composition, or the weight of primal and retail carcass cuts at wk 17 postweaning, with the exception of primal belly weight. These results indicate that feeding simple nursery diets, or nursery diets without antibiotics, compromises growth performance during the nursery period but does not affect overall growth performance between weaning and market BW, carcass characteristics, and meat quality. Thus, feed costs for nursery pigs can be reduced by feeding simple diets without compromising market BW and carcass and meat quality. [ABSTRACT FROM AUTHOR]

In Exp. 1, a total of 144 pigs (BW, 6.68 ± 0.17 kg) were weaned at 21 d, blocked by BW, and allocated to 48 pens with 3 pigs per pen. Pens were randomly assigned to 1 of 6 dietary treatments (0, 2.5, 5, 7.5, and 10% glycerol supplemented to replace up to 10% lactose in a basal starter 1 diet containing 20% total lactose, which was fed for 2 wk), and a negative control diet with 10% lactose and 0% glycerol. A common starter diet was fed for the next 2 wk. In Exp. 2, a total of 126 pigs (BW, 6.91 ± 0.18 kg) were weaned at 21 d of age, blocked by BW, and allocated to 42 pens with 3 pigs per pen. Pigs were assigned to 1 of 6 treatments in a 2 × 3 factorial arrangement in a randomized complete block design with factors being 1) glycerol inclusion in replacement of lactose in starter 1 diets (0 or 5%) fed for 2 wk, and 2) glycerol inclusion in starter 2 diets (0, 5, or 10%) fed for 3 wk. In Exp. 1, glycerol supplementation at 10% improved (P = 0.01) ADG (266 vs. 191 g/d) and G:F (871 vs. 679 g/kg) during the starter 1 period when compared with the negative control. Incremental amounts of glycerol linearly (P < 0.05) increased ADG and ADFI, but did not affect G:F during starter 1. There was no effect of feeding glycerol during the starter 1 phase on subsequent performance during the starter 2 phase or overall. Serum glycerol concentrations increased linearly (P = 0.003) with increasing dietary glycerol, and serum creatinine (P = 0.004) and bilirubin (P = 0.03) concentrations decreased with increasing glycerol. In Exp. 2, glycerol did not affect performance during starter 1, but it linearly increased (P ⩽ 0.01) ADG and ADFI during starter 2 (464, 509, and 542 and 726, 822, and 832 g/d, respectively) and overall (368, 396, and 411 and 546, 601, and 609 g/d, respectively). At the end of the study, pigs were 1.0 and 1.5 kg heavier when fed 5 and 10% glycerol, respectively (linear, P < 0.01). Serum glycerol concentrations increased linearly during starter 2 (P < 0.001), but were not affected during starter 1. Glycerol supplementation increased serum urea N quadratically (P < 0.001) and decreased creatinine linearly (P < 0.05) in the starter 2 phase. Overall, data indicate that glycerol can be added to nursery pig diets at 10%, while improving growth performance. [ABSTRACT FROM AUTHOR]

Experiments were conducted to assess the effect of dried whey (DW; 70% lactose) or milk chocolate product (MCP; 20% lactose and 60% sugars) on wk-1 feed intake and growth performance of pigs. Diets contained 1.60, 1.40, 1.40, and 1.20% total Lys for phase 1 (d 0 to 7), 2 (d 7 to 14), 3 (d 14 to 21), and 4 (d 21 to 35), respectively. Pigs were blocked by initial BW; sex and littermates were balanced across treatment; treatments were replicated with a minimum of 5 pens of 4 pigs each. Pigs were weaned at 24, 19, and 24 d of age with an initial BW of 6.5, 6.0, or 6.3 kg for Exp. 1 to 3, respectively. In Exp. 1 and 2, the treatments were 1) negative control (NC), no lactose added, 2) positive control (PC) with DW, 3) 25% replacement of the level of DW of the PC diet with MCP (25MCP), and 4) 50% replacement of the level of DW of the PC diet with MCP (50MCP). The level of DW or combinations of DW and MCP were 20, 10, and 5% for phases 1, 2, and 3 respectively. A common diet with no lactose was fed during phase 4. In Exp. 3, the treatments were 1) NC, 2) PC, and 3) 100% replacement of the level of DW of the PC diet with MCP (100MCP). In the combined data of Exp. 1 and 2, daily collected feed intake during wk 1 was increased (P < 0.10) from d 3 to 7 for the PC pigs; on d 2, 3, 4, and 7 for the 25MCP pigs; and from d 2 to 7 for the 50MCP pigs compared with the NC pigs. There was no difference (P > 0.10) on any day of wk 1 among pigs fed the PC and MCP diets. During phase 1, ADG and ADFI were increased (P < 0.10) for the PC, 25MCP, and 50MCP pigs compared with the NC pigs, but G:F was not affected (P > 0.10). During phases 2, 3, 4, and overall, there were no differences (P > 0.10) in growth performance among pigs fed the PC and MCP diets. In Exp. 3, collected daily feed intake during wk 1 was increased (P < 0.10) from d 2 to 5 for PC pigs and on d 1 and 2 for the 100MCP pigs compared with the NC pigs. However, there was no difference (P > 0.10) on any day of wk 1 between the PC and 100MCP pigs. Growth performance was not affected (P > 0.10) during any phase of the experiment. Combined data from Exp. 1, 2, and 3 using the NC and PC diets indicated that dietary DW increased (P < 0.10) final BW and increased ADG and ADFI during phases 1, 2, 3, and overall. These results indicate that partial or total replacement of DW with MCP had no effect on wk-1 feed intake or growth performance of weanling pigs and that MCP could be considered as a formulation alternative to DW. [ABSTRACT FROM AUTHOR]

Two experiments were conducted to evaluate dietary fortification levels of a B vitamin premix for starter and grower-finisher pigs on subsequent performance responses. The objective was to determine whether the modern pig requires higher dietary levels of B vitamins than estimated by the NRC (1998). Both experiments added fat-soluble vitamins at the requirement levels (NRC, 1998) in all diets, whereas the B vitamins were added at 0, 100, 200, or 400% of the total NRC (1998) requirement levels for the starter and grower pig. ndigenous vitamin contributions from the feed grains were not included in the estimates. Each station used the same vitamin premixes but incorporated its own grain sources in the diets. The first experiment was conducted across 7 stations (Indiana, Ohio, Oklahoma, Michigan, Missouri, Nebraska, Texas) and involved 660 pigs in a randomized complete block design in 30 replicates. Complex nursery diets were fed in 2 phases. The first phase (0 to 14 d postweaning) and second phase (15 to 35 d postweaning) diets were formulated to Lys (total) levels of 1.50 and 1.30%, respectively. The results demonstrated no performance response to addition of B vitamins from 0 to 14 d post- weaning, but performances increased quadratically (P <0.01) to the 100% NRC level from 14 to 35 d postweaning and for the overall 35-d period. The second experiment was conducted across 3 stations (Ohio, Nebraska, and South Dakota) and involved 216 pigs in a randomized complete block design in 10 replicates. Corn-soybean meal mixtures were fed in 3 phases formulated to total Lys levels of 1.30% (23 to 55 kg of BW), 1.00% (55 to 85 kg of BW), and 0.78% (85 to 120 kg of BW). Pig performances increased (P < 0.01) to the 100% B vitamin level from 23 to 85 kg of BW, but there was no response to any level from 85 to 120 kg of BW. Carcass measurements demonstrated a greater LM area (P < 0.01) and a lower backfat depth (P < 0.01) to the 100% B vitamin level. One station evaluated an additional treatment (3 replicates) in which each replicate was fed a fifth diet containing the 100% dietary level of B vitamins from 23 to 85 kg of BW whereupon the B vitamins were removed from 85 to 120 kg of BW. This removal did not reduce pig performance responses for the final period or for the overall period. The results demonstrated that supplementation of B vitamins at the 100% total NRC levels for starter and grower pigs was sufficient to meet their needs, and there was no further improvement to or deleterious effect to greater dietary levels. [ABSTRACT FROM AUTHOR]

An acute stress response can be provoked by abrupt social, nutritional, and environmental changes associated with weaning, and this may disrupt homeostasis and thus compromise well-being. Manipulating environmental factors, such as photoperiod, might provide a simple way to reduce the physiological consequences that piglets experience due to weaning stress. The objective of this study was to evaluate the impacts of photoperiod manipulation across various weaning ages on leukocyte populations, lymphocyte proliferation, natural killer cytotoxicity (NK), chemotaxis, phagocytosis, and immunoglobulin G, cortisol, and BW of piglets during the nursery phase. Sixty-eight crossbred piglets were obtained from sows kept on a short-day (8 h of light/d) photoperiod from d 90 of gestation until weaning. Piglets were weaned at 14, 21, or 28 d of age and kept on a short or long (16 h of light/d) photoperiod until 10 wk of age. Piglet BW and blood samples were collected at weaning and at 6, 8, and 10 wk of age. Pigs weaned at 28 d had reduced neutrophil counts (P < 0.001), phagocytosis (P < 0.001), and lymphocyte proliferation (P < 0.05) at weaning compared with those weaned at 14 and 21 d. Pigs weaned at 21 d tended to have lower (P = 0.08) lymphocyte counts than did pigs weaned at 14 or 28 d. Pigs weaned at 14 d had reduced (P < 0.01) NK relative to those weaned at 21 or 28 d. Photoperiod also influenced pig BW and immune status. Generally, those pigs on the long-day photoperiod and weaned at 28 d were heavier (P < 0.001) than their counterparts weaned at 14 or 21 d. At 6 wk of age, NK was greater (P = 0.002) in pigs kept on a long day and weaned at 14 or 21 d than in pigs weaned at 28 d. Phagocytosis was less (P = 0.005) at 6 wk of age, but was greater at 8 wk, in piglets kept on the long day and weaned at 28 d than in long-day pigs weaned at 14 or 21 d. These results suggest that photoperiod differentially influences immune responses in piglets weaned at different ages and indicate an inverse relationship between growth and immune status. Here, weaning at 28 d and a long-day photoperiod was the treatment combination that was most physiologically beneficial to piglets, whereas a 14-d weaning and short-day photoperiod was least physiologically beneficial. [ABSTRACT FROM AUTHOR]

The objective of this experiment was to evaluate the blood profile, growth performance, and tissue mineral concentration during the nursery period in weanling pigs that received various dosages of iron at birth. A total of 70 crossbred pigs (weaning BW 6.36 ± 0.92) from 5 different injectable iron dosage treatments administered at birth (0, 50, 100, 200, and 300 mg iron from iron dextran) were used. Pigs were weighed at d 22 (weaning), 23, 24, 25, 29, 38, 44, and 52. Blood was collected from 10 pigs per treatment at the same times as above except for d 44 and analyzed for a complete blood count (CBC). A total of 3 pigs per treatment were euthanized on d 22, 38, and 52 to determine tissue mineral concentration. All pigs were fed a common nursery diet supplemented with 100 mg/kg Fe from ferrous sulfate. All data were subjected to ANOVA with the pig as the experimental unit. As injectable iron dosage at birth increased, hemoglobin concentration (Hb) increased at weaning (linear and quadratic: P < 0.05), to d 29 and then quadratically through (P < 0.05) d 38. Along with the other CBC measurements, Hb was similar between treatments at d 52. There was a quadratic response (P < 0.05) for ADG from d 22 to 52. Although by d 52, final BW peaked (quadratic: P < 0.05) for pigs receiving 100 mg iron. Iron concentration of the liver and spleen were greater (linear: P < 0.05) at weaning as iron injection dosage increased but was greater only in the liver at d 38 (P < 0.05) and the spleen at d 52 (P < 0.05). Results indicate that an iron injection administered shortly after birth is vital for proper growth and hematological functions during the nursery period. [ABSTRACT FROM AUTHOR]

Weaned pigs (n=1,722; 5.9 kg BW) were used in a 53-d study evaluating the effects of Fe injection timing on subsequent nursery pig performance. Treatments consisted of a negative control for piglets receiving no Fe injection or 200-mg of injectable Fe (GleptoForte, Ceva Animal Health, Lenexa, KS) provided on d 1, 3, 5, or 7 of age, or 200-mg on d 1 plus an additional 200-mg injection on d 12. At weaning, pigs were placed in a commercial wean-to-finish facility in a total of 15 pens with equal representation of treatments in each pen. Pigs were weighed on d 73 after birth to determine subsequent nursery growth performance. Growth data were analyzed (GLIMMIX procedure of SAS) as a completely randomized design with individual pig as the experimental unit and pen as a random effect. Increasing the age that piglets received a 200-mg Fe injection showed no evidence of difference (P >0.10) for subsequent nursery ADG (Table 1). Not providing an Fe injection after birth decreased (P=0.0001) subsequent nursery ADG and decreased (P=0.0001) d 73 BW compared to all other treatments. Providing a 200-mg injection of Fe on d 1 plus a 200-mg injection on d 12 decreased (P=0.010) subsequent nursery ADG and decreased (P=0.024) d 73 BW compared to pigs receiving a 200-mg injection on d 1 only. There was no evidence of difference (P >0.10) for nursery mortality amongst the treatments. These results suggest that providing a 200-mg Fe injection within 7 d after farrowing is sufficient for optimizing subsequent nursery growth performance. The additional 200-mg Fe injection at d 12 decreased subsequent nursery growth performance and ending BW. [ABSTRACT FROM AUTHOR]

An experiment was conducted to compare the effects of organic (Zn AA complex, ZnAA) and inorganic Zn (ZnSO4) sources on sows and their progeny during gestation and lactation and on the pigs during the nursery period. The dietary treatments were 1) a corn-soybean meal diet with 100 ppm Zn from ZnSO4 (control); 2) diet 1 + 100 ppm additional Zn from ZnSO4; and 3) diet 1 + 100 ppm additional Zn from ZnAA. Dietary additions were on an as-fed basis. Thirty-one primaparous and multiparous sows were allotted to the treatment diet beginning on d 15 of gestation and continuing through lactation. At weaning (d 17 of age), 202 pigs (63, 55, and 84 pigs for treatments 1 to 3, respectively) were allotted to the same dietary treatment as their dam. The pigs were fed a 3-phase diet regimen during the nursery period: d 0 to 7 (phase I); d 7 to 21 (phase II); and d 21 to 28 (phase III). At weaning and at the end of phase III, I gilt per replicate was killed, and the left front foot, liver, pancreas, and entire small intestine were removed. Diet had no effect (P > 0.10) on any response during gestation. During lactation, there was an increase (P < 0.10) in litter birth weight in sows fed ZnAA compared with those fed the control or ZnSO4 diets. The sows fed ZnAA nursed more pigs (P < 0.10) than sows fed the ZnSO4 diet, and they weaned more pigs (P < 0.05) than sows fed the control diet. Jejunal villus height of the weaned pigs from sows fed ZnSO4 was increased (P < 0.05) compared with those from the sows fed the control diet. During the nursery period, growth performance was not affected (P > 0.10) by diet. Pigs fed ZnSO4 had greater duodenal villus width (P < 0.05) than those fed ZnAA, and pigs fed ZnSO4 or the control diet had greater ileal villus width (P < 0.05) than those fed ZnAA. Pigs fed ZnSO4 or ZnAA had more (P < 0.05) bone Zn than those fed the control diet. Liver Zn concentration was greatest in pigs fed ZnSO4, followed by those fed ZnAA, and then by those fed the control diet (P < 0.05). Pancreas Zn was increased (P < 0.05) in pigs fed ZnSO4 compared with those fed the control diet. These results suggest that 100 ppm Zn in trace mineral premixes provides adequate Zn for optimal growth performance of nursery pigs, but that 100 ppm additional Zn from ZnAA in sow diets may increase pigs born and weaned per litter. [ABSTRACT FROM AUTHOR]

The complex environment surrounding young pigs reared in intensive housing systems directly influences their productivity and livelihood. Much of the seminal literature utilized housing and husbandry practices that have since drastically evolved through advances in genetic potential, nutrition, health, and technology. This review focuses on the environmental interaction and responses of pigs during the first 8 wk of life, separated into pre-weaning (creep areas) and post-weaning (nursery or wean-finish) phases. Further, a perspective on instrumentation and precision technologies for animal-based (physiological and behavioral) and environmental measures documents current approaches and future possibilities. A warm microclimate for piglets during the early days of life, especially the first 12 h, is critical. While caretaker interventions can mitigate the extent of hypothermia, low birth weight remains a dominant risk factor for mortality. Post-weaning, the thermoregulation capabilities have improved, but subsequent transportation, nutritional, and social stressors enhance the requisite need for a warm, low draft environment with the proper flooring. A better understanding of the individual environmental factors that affect young pigs as well as the creation of comprehensive environment indices or improved, non-contact sensing technology is needed to better evaluate and manage piglet environments. Such enhanced understanding and evaluation of pig-environment interaction could lead to innovative environmental control and husbandry interventions to foster healthy and productive pigs., (© The Author(s) 2022. Published by Oxford University Press on behalf of the American Society of Animal Science.)

Social and environmental stressors impact nursery pig performance and may be linked to gastrointestinal dysfunction. The current experiment was conducted to investigate the impact of feed and water deprivation on serum stress markers and ileal mucosal gene expression in nursery pigs. Mixed-sex pigs were allotted on the basis of IBW (7.0 kg ± 0.89) in a RCBD with treatments in a split-plot arrangement and consisting of the whole-plot factor of with or without a 24-h feed and water deprivation at weaning and the sub-plot factor of with or without a cyclic 3-d heat stress starting 27 d post-weaning. On 1, 27, and 30 d post-weaning one pig from each pen was selected, blood was collected for measurement of serum cortisol, corticotrophin releasing factor (CRF), and endotoxins, and an ileal mucosal scraping was taken and gene expression of claudin 1 (CL-1), occludin (OC), and zonula occludens 1 (ZO-1) were measured by RT PCR. There was an increase (P < 0.05) in serum CRF and endotoxins and a tendency for an increase (P = 0.09) in serum cortisol due to the deprivation 1 d post-weaning. Further, there was a tendency for an increase (P < 0.10) in serum endotoxins and CRF due to the deprivation at 27 and 30 d postweaning, respectively. Gene expression of CL-1 tended to increase (P = 0.10), and OC decreased (P = 0.05) due to the deprivation 1 d post-weaning. Expression of the OC gene decreased (P < 0.05) due to the deprivation 27 d post-weaning and OC and ZO-1 gene expression tended to decrease (P = 0.07) due to the heat stress 30 d post-weaning. These results show that post-weaning stress events alter serum stress markers and impact intestinal barrier function. [ABSTRACT FROM AUTHOR]

Water is an absolute requirement in the daily needs of the pig. It has been suggested that after weaning, pigs may not consume enough water which impacts in their hydration. It is commonly known that providing water to piglets encourages higher feed intake and improves nutrient absorption, with a positive impact on weight gain and on post-weaning feed intake adaptation, decreasing problems caused by the transition phase from the farrowing unit to the nursery. The objective of this study was to evaluate the effect of the addition of a flavor to the drinking water of piglets on their voluntary water intake and performance in the first week after weaning. Sixty (30 males and 30 females) commercial piglets were used, in a randomized block design, with 10 repetitions per treatment (with or without addition of 100g/1000 L of water of Power sweet®; Adisseo) and each repetition with 3 animals. The piglets were weighed at weaning and d 8 post weaning. Parameters evaluated were the initial and final weight; daily weight gain; average daily and total feed intake; total daily and average consumption per animal of water and correlation between feed and water consumption. The means of the variables were submitted to the Pdiff option of the SAS using the Tukey test for contrasts (P < 0.05). The addition of a flavor in the drinking water increased daily weight gain in 6.7% (P = 0.041), average daily feed consumption in 2.98% (P = 0.0014), total feed consumption in 2.96% (P = 0.0014) and increased the final weight by 1.25% (P = 0.0411) when compared the control. Feed and water intake had a positive correlation in both treatments. The addition of flavor to the drinking water increases feed and water intake, improving the piglet performance in the first week after weaning. [ABSTRACT FROM AUTHOR]

Probiotics are being considered as an alternative means to reduce pathogen infection and improve animal health especially around the time of weaning. The objective of our study was to evaluate the effects of the use of a probiotic in diets for piglets on their performance and intestinal integrity during nursery phase. Thirty-six piglets (18 barrows and 18 females), weaned at 24 days of age were distributed in a randomized block design, with six repetitions per treatment (with or without addition of 50g/ton of the probiotic Bacillus subtilis DSM 32315, GutCare®, Evonik Industries) and each repetition with three pigs per experimental unit. During the experimental period, performance parameters evaluated were body weight (BW), daily feed intake (ADFI), feed conversion, average daily weight gain (ADG) and the intestinal integrity assessed via galactose absorption capacity. The performance data were submitted to the PDIFF option of the SAS and compared using the Tukey test. During phase 1 (24 to 31 days of age) the use of the probiotic tended (P = 0.07) to improve ADG (+76 g/d) in comparison to control. As for phase 2 (32 to 39 days of age), 3 (40 to 53 days of age) and 4 (54 to 70 days of age) the use of the probiotic increased the ADFI (+118, +66 and +162 g/d, respectively; P < 0.05) and ADG (+5 and +8%, respectively for phase 2 and 3; P < 0.05) compared to control. The use of the probiotic improved (P = 0.05) nursery end BW (+1.3 kg) and overall ADFI (+8%; P = 0.046). The intestinal integrity was not affected by treatments (P > 0.10) at any stage. In conclusion, the use of the probiotic Bacillus subtilis DSM 32315 in diets for weaned piglets can be used as a viable formulation strategy to improve performance and the intestinal health of the animals during nursery phase. [ABSTRACT FROM AUTHOR]

This study investigated the effects of a postbiotic from Lactobacillus acidophilus fermentation (LAF) on pig gut microbiome during nursery. Piglets (n = 32) at weaning (day 21 ± 2) were randomized based on BW (7.4 ± 1.7 kg) and received basal diets that met NRC nutrient requirements for phase 1 (d 0-14) and phase 2 (d 14-32) post-wean. Treatments included i) NC, negative control; ii) PC, antibiotic positive control, iii) LAFa (Dia-V™ Nursery, Diamond V, IA) supplemented at 1000 ppm in phase 1 and 1500 ppm in phase 2, and iv) LAFb (Dia-V™ Nursery) supplemented at 2000 and 1000 ppm during phase 1 and 2, respectively. Fecal samples were collected on d 0, 7, 14, and 32 postwean and subjected to DNA extraction and long read Nanopore shotgun metagenomics to assess composition, function and progression of gut microbiome and their correlations with BW. On d7, PC and LAF supplemented pigs numerically were closer to microbiome of d 14 and 32 compared to NC pigs. From d 0 to 32, pigs progressed through five compositional clusters (P < 0.05). By d 32, more pigs from PC and LAF groups were exhibiting a compositional cluster that was characterized by dominance of members of Bacteroidetes phylum including several Prevotella species. From d 0 to d 32, four microbiome functional clusters were observed (P < 0.05) with varying abundances of carbohydrate-active-enzymes (CAZy). Pigs in LAF groups compared to other treatments exhibited clusters with greater abundances of CAZy that was correlated with greater BW on d 32 (P = 0.004). The 2000 ppm supplementation of LAF in phase 1 and 1500 ppm in phase 2 numerically increased all measured of diversity compared to 1000 ppm. Overall, while PC and LAF groups promoted more similar microbiome compositional clusters compared to NC, LAF pigs exhibited superior functional clusters. [ABSTRACT FROM AUTHOR]

Weaned pigs (n = 311; 5.9 kg BW) were used in a 59-d study evaluating the effects of Fe injection timing after birth on nursery pig performance and hematological criteria. Pigs were weaned at 21 d and allotted to pens based on preweaning Fe treatment with BW balanced across pens within a treatment with 5 or 6 pigs/pen and 10 pens/treatment. The preweaning treatments were a negative control receiving no Fe injection or 200-mg of injectable Fe (Gleptoforte, Ceva Animal Health, Lenexa, KS) provided in a single injection on d 2, 4, 6, 8, or 10 after birth. All pigs were fed common diets after weaning that contained 110 mg/kg of added Fe as FeSO4 provided from the trace mineral premix. Growth data were analyzed as a completely randomized design with pen as the experimental unit. Hematological criteria were measured as a repeated measure with pig as the experimental unit. Overall, increasing the age of pigs receiving a 200-mg Fe injection from 2 to 4 or 6 d after birth increased (quadratic; P = 0.013) d 80 ending BW with a decrease in BW when Fe was provided on d 8 or 10 (Table 1). Not providing an Fe injection after birth worsened (P < 0.05) ADG, ADFI, and d 80 ending BW. Significant treatment×day interactions (P < 0.001) were observed for Hgb and Hct values. These interactions occurred because pigs not receiving an Fe injection after birth had values that increased from d 21 to 35 while pigs receiving an Fe injection had values that decreased from d 21 to 35. While it is common practice to provide an Fe injection within the first 48 hours of birth, these results suggest delaying injection until d 4 or 6 may increase nursery final weight. [ABSTRACT FROM AUTHOR]

Weaned pigs (n = 308; 5.7 kg BW) were used in a 42-d study evaluating the effects of increasing injectable Fe dose at processing (d 3 after farrowing) on subsequent nursery pig performance and hematological criteria. Pigs were weaned on d 21 and allotted to pens based on previous Fe treatment with BW balanced across pens within a treatment with 5 or 6 pigs/pen and 10 pens/treatment. Treatments applied at processing were a negative control receiving no Fe injection or increasing injectable Fe (Gleptoforte, Ceva Animal Health, Lenexa, KS) to provide 50, 100, 150, 200-mg, or 200-mg plus 100-mg on d 11 post-farrowing. All pigs were fed the same diets after weaning containing 110 mg/kg of Fe from FeSO4 provided from the trace mineral premix. Growth data were analyzed as a CRD with pen as the experimental unit. Hematological criteria were analyzed as a repeated measure with pig as the experimental unit. Overall, increasing injectable Fe improved (linear; P < 0.05) ADG and ADFI (Table 1). Increasing injectable Fe up to 150 mg improved (quadratic; P = 0.011) G:F with a worsening G:F thereafter. There was no evidence of difference in growth performance (P > 0.10) between the 200-mg and the 200 + 100 mg injectable Fe treatments. Significant treatment×day interactions (P < 0.001) were observed for Hgb and Hct because pigs receiving an Fe injection less than 150-mg had increasing values through nursery while all other pigs had values remaining constant until d 63 after birth with no evidence of difference (P > 0.10) amongst all treatments at d 63 after birth. These results suggest that providing a 200-mg Fe injection at processing provides the greatest growth performance in the nursery and Fe in the diet is sufficient to meet the pigs' Fe requirement to restore blood Fe status at the end of the nursery. [ABSTRACT FROM AUTHOR]

Four hundred (PIC 337 X Camborough, PIC, Hendersonville, TN) and 800 (PIC 359 X C29) barrows and gilts were used to determine the impact of avilamycin (Kavault®, Elanco, Greenfield, IN) on nursery pig performance. Upon weaning, the lightest 10% of pigs were sorted off to form one replication and the remaining pigs were sorted by sex and placed into blocks with 25 pigs/pen. Six of the 48 pens were assigned to a non-feed grade medication control treatment. Remaining blocks were assigned to 1 of 3 treatments (50 g Mecadox/ton, 73 g Kavault/ton d0 to d21, 73 g Kavault/ton d0 to d42). Diets were formulated to meet or exceed NRC (2012) recommendations. Pen weights and feed intake information were collected for calculation of ADG, ADFI, and F:G. Pigs were vaccinated against porcine circovirus, Mycoplasma hyopnuemoniae, Salmonella , and Lawsonia. Diagnostic samples showed presence of E. coli and Salmonella. Pigs were PRRSv and PEDv negative. Data were analyzed as a completely randomized design using the PROC MIXED procedure of SAS with pen as experimental unit and treatment as a fixed effect. LSMeans were considered significant at P ≤ 0.05 and considered a trend at P > 0.05 and P ≤ 0.10. Final body weight (d42) was not significantly different (P = 0.26), but there were numerical improvements in body weight for all medication treatments compared to the control (0.68, 0.68, and 1.5 kg for Mecadox, Kavault 21 d and Kavault 42 d respectively). Overall ADG (0.46, 0.45, 0.48, 0.45 kg, respectively) was greatest and F:G was lowest for the Kavault 42d treatment, although differences were not always significant (P > 0.05). Feeding medications numerically lowered the percentage of injectable medication intervention compared to controls (110.8, 12.7, 137.2, and 156.0%, respectively). Avilamycin appears to be an effective medication option for pigs in 42 d nursery programs but the anticipated response may differ depending on feeding duration. [ABSTRACT FROM AUTHOR]

We previously reported that crowding in the nursery decreased growth rate and affected blood chemistry and hematology measures in gilts. In the current experiment, weanling gilts were allowed decreased floor space in the nursery to determine effects of crowding on their future litter sizes and retention as sows. Of 2,537 gilts classified at weaning as large (6.92 kg), medium (4.42 kg), or small (5.60 kg) and reared in nursery pens of 14, 11, or 8 pigs (to allow 0.15, 0.19, or 0.27 m2 floor space/pig, respectively), 1,453 gilts were selected for breeding and distributed among 11 sow farms. As expected, total litter size (12.94, 13.28, and 13.99; SE = 0.13) and born alive (12.21, 12.64, and 13.23; SE = 0.11) increased (P < 0.01) from parity one to three. A tendency (P = 0.08) existed for a quadratic relationship between space and total litter size [13.39, 13.54, and 13.27 (SE = 0.13) for gilts allowed 0.15, 0.19, or 0.27 m2 floor space/pig, respectively]. A linear effect of pig size (P = 0.03) on stillborns was detected (0.64, 0.75, and 0.75, for small, medium, and large, respectively). There was no effect of space on the percentages of gilts completing zero (P = 0.36), one (P = 0.35), two (P = 0.32) or three (P = 0.50) parities. However, the percentage of small gilts completing zero parities was greater (P < 0.01), and the percentage completing one parity was less (P < 0.01) than for large or medium gilts. Abortion rate was greater (P < 0.01) in gilts classified as small (2.51%) or medium (1.36%) compared with large (0.20%). Floor space allowed in the nursery did not remarkably affect litter sizes or retention through three parities in sows. Compared with larger pigs, however, more small pigs entering the breeding herd did not complete a parity and displayed a greater abortion rate. [ABSTRACT FROM AUTHOR]

Poor starting nursery pigs are a common source of frustration for pork producers due to suboptimal lean tissue production and failure to thrive. This is generally a multifactorial issue with potential nutritional, infectious and management contributors. Commonly encountered respiratory and enteric pathogens include porcine reproductive and respiratory syndrome virus (PRRSV), influenza A virus (IAV), porcine enteric coronaviruses (TGEV/PEDV/PDCV), and group A, B, and C rotaviruses, as well as Salmonella typhimurium , enterotoxigenic Escherichia coli , Streptococcus suis , and Haemophilus parasuis. Infection with one or more of these agents can ultimately antagonize pig health and performance. However, while these specific pathogens may be causing an observed disease symptom, pigs may have been predisposed to infection due to various management, nutritional, and environmental risk factors. As many of these potential pathogens are endemic in production systems, it is important to remember that simply detecting a potential pathogen within a population is often not sufficient to assign cause for poor growth and production. To help fully interpret the impact of a detected agent, diagnostic efforts should focus on providing proof that the agent is actually causing disease. Molecular detection methods, such as PCR, are increasingly available for common pathogens and have high diagnostic sensitivity but lower diagnostic specificity. This paper will discuss the clinical signs and gross and microscopic lesions associated with common nursery pig pathogens, as well as proper sampling and diagnostic testing necessary to detect and confirm disease following infection with these agents. [ABSTRACT FROM AUTHOR]

A total of 38 mixed parity sows were used from 28-d of gestation until weaning to determine the effects of medium chain fatty acids (MCFA) in sow and nursery pig diets on litter characteristics and growth performance. On 28-d of gestation, sows were blocked by parity and body weight (BW), and allotted to either a control diet (UNSUP) or a control diet plus 0.3% inclusion of DaaFit Plus (MCFA) fed during gestation and lactation. At weaning, piglets (n=432) were allocated in a 2x2 factorial based on maternal diet (UNSUP or MCFA) and post-weaning diet (UNSUPnurs or MCFAnurs) in a 3-phase nursery pig feeding program lasting 42 days. Individual piglets were weighed at birth, 7-d, at weaning and every 2 weeks post-weaning. A flu outbreak occurred during the latter part of gestation leading to high overall stillborn rate (11%). There was no impact of MCFA supplementation on sow performance (P>0.14). During the suckling period, MCFA fed to sows had no impact on piglet weights or ADG (P>0.82). In the nursey period, overall gain (0.112±0.02 kg) was low in the first two weeks possibly due to health challenges. Supplementation of MCFA to sows or nursery pigs had no impact on body weights during the nursery period (P>0.32); however, absolute differences between groups increased with week [wean, 0.10kg; wk 2, 0.14kg; wk 4, 0.71kg; wk 6, 0.83kg) to the advantage of MCFA fed pigs. Pigs from MCFA fed sows had greater feed intake (P< 0.02) from 14 to 28-d and decreased gain:feed (P < 0.04) from 28 to 42-d compared to pigs from UNSUP sows. Overall, sow and nurser-y pigs fed MCFA had numerically greater 42-d BW, ADG, and ADFI. In conclusion, despite health challenges, supplementation with MCFA in gestation, lactation or in the nursery period improved piglet performance. [ABSTRACT FROM AUTHOR]

An experiment was conducted to determine the effects of added Zn level on growth performance and hemoglobin of nursery pigs. A total of 673 pigs (initial BW = 6.0 kg) were used in a 45-d trial. There were 3 treatments based on added Zn level: 100, 2,000, or 3,000 mg/kg from Zn oxide. Experimental diets were fed for 21 d. After that, pigs were fed a common corn and soybean meal-based diet with 100 mg/kg added Zn for 24 d. There were 8 replicates per treatment. Pigs were weighed approximately every 10 d to evaluate growth performance, and blood samples were collected for hemoglobin analysis. Data was analyzed with SAS MIXED procedure. From d 0 to 10, there was a linear improvement (P < 0.05) in ADG, ADFI, and G:F with increasing Zn level. From d 10 to 21, increasing Zn level resulted in higher ADFI (linear, P = 0.009). However, there was no difference (P > 0.10) in ADG and G:F. From d 0 to 21, pigs fed increasing added Zn had improved (linear, P < 0.05) ADG and ADFI. From d 21 to 45, pigs previously fed high levels of added Zn had higher ADFI (linear, P = 0.023), but there was no evidence for differences (P > 0.10) for ADG and G:F. Overall (d 0 to 45), pigs fed increasing added Zn levels had improved (linear, P < 0.05) ADG, ADFI, and final BW. A quadratic response (P < 0.05) was observed for hemoglobin on d 10 and 45, with no differences (P > 0.10) observed on d 21. In summary, pigs fed high levels of added Zn presented improved growth performance. Although the response was linear in nature, the differences between pigs fed 2,000 or 3,000 mg/kg Zn were minimal for the response variables evaluated. [ABSTRACT FROM AUTHOR]

Weaning induces major structural and function changes to the small intestine of pigs and they transition from milk to solid feedstuffs. Thus, the objective of this study was to determine how intestinal morphology and function markers relate to feed intake and growth rates of nursery pig. Forty-eight weaned pigs (5.63 ± 0.50 kg) were randomly selected, individually penned and fed a common diet. Pig bodyweights and feed intake were determined at d 2, 7, and 21. At each time point, 16 pigs were randomly selected and euthanized. Sections of ileum were assessed for morphology [villus height (VH), crypt depth (CD) and VH:CD] and ex vivo transepithelial resistance (TER), macromolecule permeability (FD4), and active transport of glucose and glutamine via modified Ussing chambers. Within each period (d 0-2, 0-7, and 0-21), Pearson correlations were performed between ADG, ADFI, VH, VH:CD, TER, FD4 and active transport of glucose and glutamine. At d 2 post-weaning, no correlations (P > 0.05) were observed between performance and intestinal variables. By d 7, moderate positive correlations between VH and ADFI (r = 0.69, P = 0.005), VH and ADG (r = 0.68, P = 0.006) were reported. At 21 d post-weaning, moderate positive correlations were still observed for VH and ADFI (r = 0.55, P = 0.026) and between VH and ADG (r = 0.51, P = 0.042). Interestingly, ADFI and ADG tended to be negatively correlated with active glucose transport (r = -0.45, P = 0.083 and r = -0.47, P = 0.064, respectively) and active glutamine transport (r = -0.45, P = 0.083 and r = -0.46, P = 0.073, respectively). Markers of ileal integrity (TER and FD4) were not correlated with ADG or ADFI at any time point. Altogether, these data highlight the importance of intestinal morphology on early nursery pig performance. [ABSTRACT FROM AUTHOR]

Mycotoxins (MTX) such as deoxynivalenol (DON), fumonisins (FUM), and zearalenone (ZEN) are a few of the most prevalent mycotoxins in livestock feed. Effects of MTX can vary based on contamination and type, but include losses in performance, immune function and reproduction impacting profitability. Effectiveness of mitigation strategies for MTX can greatly vary depending on type and contamination level. Therefore, the trial objective was to evaluate an in-feed mitigation strategy [Biofix® Plus (BPL), 1.5 kg/MT inclusion, BIOMIN America, Inc., Overland Park, KS] on nursery pig performance during a natural mixed MTX challenge. A total of 105 newly weaned pigs (BW = 5.5 ± 0.2 kg) were allotted to 1 of 4 treatments in a 2 × 2 factorial design with 2 MTX contamination levels [low (L-MTX) and high (H-MTX); Table 1] and 2 BPL levels [without (Control) and with (BPL)] with 3 pigs per pen and 8 to 9 pens per treatment for a 5-week trial. Data were analyzed using the GLIMMIX procedure of SAS with main effects of MTX and BPL and their interaction. There was no interaction of MTX and BPL on any of the cumulative 5-week performance metrics, therefore only main effects will be discussed. Average pig BW at 5-week was reduced (P < 0.05) in H-MTX compared with L-MTX diets (21.5 vs 18.5 kg, respectively). Similarly, ADG and ADFI were reduced (P < 0.05) in H-MTX pigs compared with L-MTX pigs. Feed efficiency was numerically reduced (P = 0.050) in H-MTX pigs compared with L-MTX pigs. However, BPL fed pigs had increased (P < 0.05) feed efficiency compared with pigs not fed BPL. Thus, MTX did effect BW, ADG, and ADFI and BPL was able to increase feed efficiency regardless of MTX level suggesting that BPL should be considered as a mitigation strategy to address mixed MTX challenges. [ABSTRACT FROM AUTHOR]

An experiment was conducted to determine the effects of the initial nursery diet budget on growth performance. A total of 3,264 pigs (initial BW = 5.5 kg), placed in pens with 51 pigs each, were used in a 45-d trial. There were 4 treatments consisting of different feed budgets of the initial nursery diet: 4.1 kg, 5.4 kg, 6.8 kg, or 8.2 kg. The experimental diet was corn, soybean meal, and whey permeate-based and contained 1.38% SID Lys. After the allocated budget was consumed, pigs were provided a common corn and soybean mealbased diet. There were 16 replicates per treatment. Pigs were weighed weekly to calculate ADG, ADFI, and G:F. Data were analyzed with SAS MIXED procedure. In the first 14 d of the trial there was no evidence for differences (P > 0.10) in growth performance as all pigs were receiving their allocated budget of the initial diet. From d 14 to 21 as well as d 0 to 21, pigs that received a budget of 6.8 or 8.2 kg had improved ADG (quadratic, P < 0.05) and G:F (linear, P < 0.05) compared to those fed budgets of 4.1 or 5.4 kg. From d 21 to 45, when all pigs received a common diet, there was no evidence for differences (P > 0.10) in ADG. However, there was a linear response (P < 0.05) in G:F, with pigs previously fed the lowest feed budget presenting improved G:F. Overall (d 0 to 45), there was an improvement (linear, P < 0.05) in ADG and ADFI as feed budgets increased, with the best performance observed when pigs were fed 6.8 or 8.2 kg of the initial nursery diet. In conclusion, providing a 6.8 or 8.2 kg budget of the initial nursery diet resulted in improved overall nursery performance. [ABSTRACT FROM AUTHOR]

A total of 1,296 pigs (PIC L337×1050; initially 4.8 kg) were used in a 42-d study to evaluate cellulose in diets with and without pharmacological levels of Zn on nursery pig performance. Our hypothesis was that added fiber (cellulose) may provide more benefit in diets without ZnO. Pens were assigned to 1 of 4 dietary treatments in a RCBD by BW with 27 pigs/pen and 12 pens/treatment. Dietary treatments were arranged in a 2×2 factorial with main effects of cellulose (0 vs 1%; J. Rettenmaier USA, Schoolcraft, MI) and Zn (200 vs. 3,000 mg/kg in phase 1 and 110 vs. 2,000 mg/kg in phase 2). Treatment diets were formulated in two phases fed from d 0 to 7 and 7 to 21 with a common diet fed from d 21 to 42 post-weaning. Pig weights and feed disappearance were collected weekly to determine ADG, ADFI, and G:F. On d 16 or 17, fecal samples were collected from 3 pigs/pen to determine fecal DM, and all pens were visually evaluated for fecal consistency. There were no Zn×cellulose interactions. For the experimental and overall period, pigs fed diets containing added Zn had increased (P < 0.001) ADG, ADFI, G:F and BW while those that were fed cellulose had decreased (P < 0.05) ADG. For fecal dry matter, there was no evidence for difference (P >0.10) between any of the treatments but those fed added ZnO had visually firmer feces as evidenced by lower (P < 0.001) fecal scores. When fed a common diet from d 21 to 42, pigs previously fed added ZnO had increased (P < 0.001) ADG (502 vs. 523 g/d) and ADFI (697 vs. 734 g/d). In conclusion, there were no interactive effects between added cellulose and Zn; however, cellulose reduced ADG while the inclusion of pharmacological levels of Zn improved all growth criteria. [ABSTRACT FROM AUTHOR]

The objective was to evaluate the effect of IFTA NBS on productive performance in pigs from nursery until the end of 1st grow-finish phase. Total of 1,200 pigs (PIC 337 x 1050; PIC, Hendersonville, TN) were allotted in a randomized complete block design (RCBD) and assigned to blocks based on weight and sex, random allocated to pens with 25 pigs/pen. Diet changes occurred in 4 phases: N1 lasting 7 days, N2 14 days, N3 21 days and F1 21 days. Animals were random assigned to 4 treatments: T1) zinc oxide (ZnO) during N1 (3000 ppm) and N2 (2500 ppm) with no antibiotics; T2) carbadox at 50 g/ton in N1 and N2; T3) IFTA NBS at 500 g/ton during N1, N2 and N3; and T4) IFTA NBS at 500 g/ton during N1, N2 and N3 along with ZnO in N1 (3000 ppm) and N2 (2500 ppm). Treatments were fed a common diet during F1. Outcomes were analyzed as RCBD using SAS PROC GLIMMIX with pen as experimental unit, treatment as main effect and block as random effect. There were significant differences (P < 0.05) in weights and average daily gain (ADG) between T2 and T3 during N2. Significant differences on average daily feed intake (ADFI) were observed between T1 and T2 vs. T3 during N2, and between T2 and T3 during N3. During nursery period (N1-N3), ADG and ADFI were different (P < 0.05) between T2 and T3. By the end of the trial, a significant difference in gain:feed between T2 and T3 was detected. Under the conditions of this study, IFTA NBS in combination with ZnO could replace carbadox as it obtained similar weight and FCR during nursery. In addition, the response on gain:feed during the first grow-finish phase deserves further investigation since suggests a beneficial residual effect of IFTA NBS. [ABSTRACT FROM AUTHOR]

A total of 360 barrows (DNA 200×400; initially 5.6 kg) were used to evaluate yeast-based probiotics (Phileo by Lesaffre, Milwaukee, WI) in diets with or without pharmacological levels of Zn on growth and fecal Escherichia coli antimicrobial resistance (AMR). There were 5 pigs/pen and 18 pens/treatment. Dietary treatments were arranged in a 2×2 factorial with main effects of yeast pre- and probiotics (0 vs. 0.10% Actisaf Sc 47 HR+, 0.05% SafMannan, and 0.05% Nucleosaf in phase 1 then concentrations were lowered by 50% in phase 2) and pharmacological levels of Zn (110 vs. 3,000 mg/kg in phase 1 and 2,000 mg/kg in phase 2 provided by zinc oxide). Treatments were fed in two phases from d 0 to 7 and 7 to 21 with a common diet fed from d 21 to 42 post-weaning. There were no probiotics×Zn interactions. From d 0 to 21, pigs fed pharmacological Zn had increased (P < 0.001) ADG and ADFI; however, there were no effects of added pre- and probiotics. Fecal samples were collected on d 4, 21, and 42 from the same three pigs/pen for AMR profiles and fecal dry matter (DM). On d 4, pigs fed pharmacological Zn had greater fecal DM (P = 0.043); however, no differences were observed on d 21 or 42. E. coli was isolated from fecal samples and species confirmation was accomplished by PCR detection of uidA and clpB genes. Microbroth dilution method using SensititreTM CMV3AGNF panel was used to determine antimicrobial susceptibilities of E. coli isolates to 14 different antimicrobials. There was no evidence for differences in AMR of fecal E. coli isolates to antibiotics by added pre- and probiotics or Zn. Results suggest that pharmacological levels of Zn stimulate intake and growth and improve fecal consistency in the nursery with no statistical response from added pre- and probiotics. [ABSTRACT FROM AUTHOR]

This study aimed to estimate the net energy value of expelled, extruded soybean meal (MSBM) relative to dehulled, solvent-extracted soybean meal (SBM) and determine its effects on growth performance of late nursery pigs. Analyzed values for CP, EE, CF, and lysine for the SBM were 47.28%, 0.47%, 3.80%, and 3.00% while the MSBM contained 47.41%, 6.88%, 5.32%, 2.99% respectively. A total of 297 pigs (DNA 200 x 400) were placed into 60 pens (2 rooms of 30 pens) with 5 pigs per pen balanced by gender and weaning weight. Pigs were fed common diets for 21 days. Then, pens of pigs (BW 9.3 kg) were randomly assigned to one of five treatments to provide 12 replications per treatment. Treatments consisted of increasing amounts of MSBM replacing SBM in the diet (0, 25, 50, 75, 100%). All diets were fed for 28 days and were formulated to 1.30% standardized ileal digestible lysine and met or exceeded NRC (2012) recommendations for lysine:amino acids, calcium, and phosphorus. The SBM diet was formulated to 2421 kcal/kg and net energy (NE) was not balanced between diets. Data were analyzed using Proc GLIMMIX (SAS 9.4; Cary, NC) with pen as the experimental unit and room as the blocking factor. There was no evidence of differences in ADG and ADFI in pigs fed diets with increasing concentrations of MSBM. Pigs fed diets with increasing concentrations of MSBM had improved (linear, P < 0.001) G:F and caloric efficiency on an NE basis. In conclusion, using caloric efficiency to estimate NE of the MSBM relative to SBM, MSBM was estimated to have a value of 123% of SBM NE or 2566 kcal/kg. This increase in NE resulted in improved feed efficiency of nursery pigs. [ABSTRACT FROM AUTHOR]

Ingestion of mycotoxins can result in many problems, including decreased growth rates and immune suppression. The present study aimed to evaluate the impact of the supplementation of a mycotoxin deactivator composed by adsorbent clay minerals; inactivated fermentation extracts of Saccharomyces cerevisiae; and blend of antioxidants, organic acids, and botanicals in diets containing added mycotoxins for nursery pigs on their performance and antioxidant status. Ninety pigs weaned with 24 d of age (7.12 ± 0.68 kg of BW) were used. Pigs were housed in pens of three animals each according to body weight, litter origin, and sex. The dietary treatments consisted of feeding the pigs with a standard control diet as negative control (NC; mycotoxin levels at accepted regulatory Brazilian Ministry of Agriculture standards; deoxynivalenol (DON): <100 μg/kg; zearalenone (ZEA): <20 μg/kg; fumonisins (FB): <1 mg/kg); the standard diet added with mycotoxins to reach a low contamination level is considered as positive low (PCL-; DON: 900 μg/kg; ZEA: 100 μg/kg; FB: 5,000 μg/kg) without deactivator; a positive low added the deactivator at an inclusion rate of 1 kg/ton (PCL+); the standard diet added with mycotoxins to reach a high contamination level is considered as positive high (PCH-; DON: 4,500 μg/kg; ZEA: 500 μg/kg; FB: 18,000 μg/kg) without the deactivator; and a positive high added the deactivator at an inclusion rate of 5 kg/ton (PCH+). Pigs were individually weighed at the beginning and at the end of each phase and feed intake recorded based on daily pen intake during the experiment. On days 7, 19, 34, and 43 post-weaning, blood samples were drawn for antioxidant analyses. Antioxidant enzymes (glutathione peroxidase [GPx] and total superoxide dismutase [TSOD]), vitamins [Vit A, E, and C], and malondialdehyde [MDA]) were evaluated in erythrocyte and plasma samples. Pigs challenged with mycotoxins presented lower performance traits, decrease in the efficiency of central antioxidant systems (↓GPx, ↓TSOD, ↓Vit A, ↓Vit E, and ↓Vit C), and a higher oxidative damage to lipids (↑MDA) when compared with the control and deactivator-associated treatments. Our findings showed that the use of a mycotoxin deactivator can mitigate the negative impacts on performance and oxidative stress when animals are subjected to diets contaminated by different levels of mycotoxins., (© The Author(s) 2021. Published by Oxford University Press on behalf of the American Society of Animal Science. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

An experiment was conducted to determine the effects of Zn level and Ca source on nursery performance. Treatments were arranged in a 2 × 2 factorial with main effects of added Zn (100 or 3,000 mg/kg) and Ca source (limestone or Ca citrate). The basal level of Zn (100 mg/kg) was from organic source, whereas the 3,000 mg/kg was created with the inclusion of 2,900 mg/kg Zn oxide. A total of 3,701 pigs (PIC 337 × Camborough), initially 5.4 kg, were used with 18 replicates per treatment. Experimental diets were fed for 19 d, followed by a common diet from d 19 to 49. Pigs were weighed and feed disappearance measured to calculate ADG, ADFI, and G:F. Data were analyzed with SAS MIXED procedure. There were interactions (P < 0.05) between Zn and Ca for G:F from d 10 to 19 and 0 to 19. From d 10 to 19, feeding 3,000 mg/kg added Zn improved G:F with both Ca sources, but the magnitude of improvement was greater when diets contained Ca citrate. From d 0 to 19, only pigs fed Ca citrate presented improvement in G:F when fed 3,000 mg/kg added Zn. For main effects, feeding 3,000 mg/kg added Zn improved (P < 0.05) ADG and G:F from d 0 to 10. From d 10 to 19 and 0 to 19, feeding 3,000 mg/kg added Zn increased (P < 0.05) ADG and ADFI. During the common period (d 19 to 49), pigs previously fed 100 mg/kg added Zn had improved (P < 0.01) G:F. Overall (d 0 to 49), no differences (P > 0.10) in performance were observed. In conclusion, there were no major differences in performance between Ca sources. Pigs fed 3,000 mg/kg added Zn presented improved growth performance from d 10 to 19 but not overall. [ABSTRACT FROM AUTHOR]

A 20-d experiment was conducted to evaluate the effects of added Zn and Cu on growth performance of nursery pigs. Treatments were arranged in a 2 × 2 factorial treatment structure with main effects of added Zn (100 or 3,000 mg/kg of diet) and Cu (10 or 200 mg/kg of diet). Basal Zn and Cu levels (100 and 10 mg/kg, respectively) were from organic sources, while the added high levels (2,900 and 190 mg/kg, respectively) were from Zn oxide and Cu hydroxychloride. A total of 784 pigs (PIC 337 × Camborough), initially 6.0 kg, were used with 7 replicates per treatment. Experimental diets were corn, soybean meal, and whey permeate-based and contained 1.38% SID Lys. Pigs were weighed and feed disappearance measured to calculate ADG, ADFI, and G:F. Data were analyzed with SAS MIXED procedure. From d 0 to 10, there was no evidence (P > 0.10) for interactive or main effects of Zn or Cu. From d 10 to 20 and overall (d 0 to 20), there was an interaction (P < 0.05) between Zn and Cu for G:F. From d 10 to 20, pigs fed 10 mg/kg added Cu had improved G:F when 3,000 mg/kg added Zn was fed; however, pigs fed 200 mg/kg added Cu had similar G:F regardless of added Zn level. There was no evidence (P > 0.10) for interaction for ADG or ADFI, indicating an additive Zn and Cu effect. Feeding 3,000 mg/kg added Zn or 200 mg/kg added Cu improved ADG, ADFI, and final BW with the highest performance observed when feeding both 3,000 mg/kg added Zn and 200 mg/kg added Cu. In summary, feeding high levels of Zn or Cu did not impact the first 10-d postweaning performance, but Zn and Cu effects were observed in the subsequent 10-d and overall performance. [ABSTRACT FROM AUTHOR]

Two experiments were conducted to determine the effects of a functional protein (FXP; Ani-Tek Group, LLC, Shelbina, MO) on growth performance of nursery pigs. A total of 840 pigs (PIC 337 × Camborough), initially 5.5 kg, were used with 28 pigs per pen and a total of 15 replicates per treatment. There were two treatments, which consisted of a control diet and the control diet with added FXP. The experimental diets were corn, soybean meal, and whey permeate-based and contained 3,000 mg/kg added Zn. The inclusion of FXP was 0.3% of the diet. Experimental diets were fed for 23 d, followed by a common corn and soybean meal-based diet from d 23 to 48. Pigs were weighed and feed disappearance measured to calculate ADG, ADFI, and G:F. There was no evidence (P > 0.10) for treatment × experiment interactions, thus data was combined for statistical analysis using the MIXED procedure of SAS. From d 0 to 23, pigs fed diets containing FXP had higher (P < 0.05) ADG, ADFI, and BW and a tendency (P = 0.053) for improved G:F. During the common period (d 23 to 48), pigs previously fed FXP had a tendency (P < 0.10) for higher ADG and ADFI. Overall (d 0 to 48), pigs that received FXP had higher (P < 0.05) ADG, ADFI, BW, and a tendency (P = 0.055) for improved G:F. In conclusion, the inclusion of the functional protein improved growth performance of nursery pigs. [ABSTRACT FROM AUTHOR]