Search

A cooperative study comprising growth performance, bone mineralization, and nutrient balance experiments was conducted at 11 stations to determine the standardized total-tract digestible (STTD) P requirement of 20-kg pigs using broken-line regression analysis. Monocalcium phosphate and limestone were added to a corn-soybean meal-based diet at the expense of cornstarch to establish 6 concentrations of STTD P from 1.54 to 5.15 g/kg in increments of 0.62 g/kg at a constant Ca:total P of 1.52:1.0. Diets were fed to 936 pigs (average initial BW of 19 kg) in 240 pens for 20 replicate pens of barrows and 20 replicate pens of gilts per diet. As STTD P increased from 1.54 to 5.15 g/kg of the diet for d 0 to 14, 14 to 28, and 0 to 28, the ADG, ADFI, and G:F increased (P < 0.01). Barrows gained and ate more (P < 0.05) than gilts during d 14 to 28 and 0 to 28. There was no interaction between sex and STTD P concentration for any of the growth performance response criteria. There were both linear and quadratic increases (P < 0.05) in mineral density and content of ash, Ca, and P in the femur expressed as a percentage of dry, fat-free metacarpal as dietary STTD P increased. Furthermore, the maximum load of the femur and mineral density and content and maximum load as well as the Ca and P expressed as a percentage of metacarpal ash linearly increased (P < 0.01) with increasing dietary concentrations of STTD P. There were both linear and quadratic increases (P < 0.01) in apparent digestibility and retention of P with increasing concentrations of STTD P in the diets. Digestibility and retention of Ca linearly (P < 0.01) increased with increasing dietary concentrations of STTD P. Breakpoints determined from nonlinear broken-line regression analyses revealed estimates of 4.20 ± 0.102, 3.20 ± 0.036, or 3.87 ± 0.090 g/kg for ADG during d 0 to 14, 14 to 28, or 0 to 28, respectively. Corresponding estimates using G:F as the response criterion were 4.34 ± 0.146, 3.38 ± 0.139, or 4.08 ± 0.195 g/kg. When mineralization of the femur was used as criteria of response, estimates of STTD P requirement were 4.28, 4.28, or 4.34, g/kg for mineral density, mineral content, or maximum load, respectively. Using mineralization of the metacarpal as criteria of response, estimates of STTD P requirement ranged from 3.5 to 5.0 g/kg depending on the metacarpal response criteria. The study provided empirical estimates of STTD P requirements of 20- to 40-kg pigs. [ABSTRACT FROM AUTHOR]

Assessment of nutrient variability, feed value, ensiling capability, intake, and digestibility of grocery food waste recycled from large retail stores was conducted in 3 experiments. In Exp. 1,115 proximate nutrient analyses of grocery byproduct feed (GBP) from stores in the southern United States from April 8, 2011, to November 18, 2012, were evaluated for variation in nutrient concentration. Grocery byproduct feed was characterized as being a readily fermentable, high-moisture energy feed with an average DM content of 17.5 ± 3.7% and TDN of 89.8 ± 7.1%. In Exp. 2 and 3, grocery food waste consisting of fruit, vegetables, and bakery items from large retail stores in the Atlanta, GA, area was used for ensiling and feeding studies. The GBP material for Exp. 2 was processed on farm into homogenous slurry and treated to reduce its moisture content and preserved in experimental silos. Drying treatments included 3 levels of citrus pulp substitution (8, 16, and 24% as-fed basis), or passively removing liquid as seepage after stacking for 24 h, or oven diying (24 h at 80°C). All GBP mixtures effectively ensiled after 28 d, as determined by changes in pH, soluble carbohydrates, and fermentation acids. Ensiled GBP was moderately stable during 72-h aerobic exposure. In Exp. 3, a feeding/digestibi1ity trial, 8 yearling Holstein steers were used in a replicated 4 x 4 Latin Square and fed 4 incremental levels of ensiled GBP in total mixed rations (TMR). Steers were fed 0, 18, 36, and 54% ensiled GBP as part of a TMR containing 68% wheat silage and 32% concentrate on a DM basis. The rations averaged 35.9,30.7,26.8, and 23.8% DM with incremental levels of GBP. Steers increased DM intake and digestibility when fed increasing GBP (P < 0.5). Digestible energy and TDN were linearly related to the level of GBP fed (P < 0.01). The TDN content of GBP was 82.7% (DM basis) and similar to predicted TDN values from commercial feed analyses of GBP. The feeding and nutritive value of ensiled GBP indicates it can be priced to be used effectively as an energy supplement in TMR for cattle. [ABSTRACT FROM AUTHOR]

Collaborative studies comprising growth performance and metabolism experiments were conducted to reevaluate growth performance and nutrient and energy utilization responses of nursery pigs to dietary lipid sources and levels. Two lipid sources (soybean oil or tallow) were included at the rate of 1%, 3%, or 5% at the expense of cornstarch in a 2 × 3 factorial arrangement for 6 diets, and Lys was added to maintain a constant calorie:Lys ratio. A growth performance experiment (d 0 to 7, d 7 to 21, and d 21 to 35 postweaning) involving a total of 822 crossbred pigs was conducted at 9 research stations. Each station contributed 2 to 7 replicate pens with 4 to 6 pigs per pen, resulting in a total of 28 replicate pens per diet. The initial BW ranged from 5.9 to 7.3 kg, and the final BW ranged from 20.9 to 28.9 kg. Diets fed during d 7 to 21 and d 21 to 35 were evaluated with 120 barrows in 2 metabolism experiments with 10 individually fed barrows per diet to determine digestibility and retention of nutrients and energy. Lipid source and the interaction between lipid level and source did not affect growth performance. Lipid did not affect growth performance from d 0 to 7. There was a quadratic decrease (P < 0.05) in ADG with increasing level of added lipid only during d 7 to 21 postweaning. The ADFI was decreased (P < 0.01) both during d 7 to 21 and d 21 to 35 postweaning with increasing level of lipid supplementation. A linear improvement (P < 0.001) in G:F with increasing level of lipid supplementation occurred during both d 21 to 35 and d 0 to 35 postweaning. There was a linear increase in DE, ME, and nitrogen-corrected ME (MEn) of diets fed during d 7 to 21 postweaning with increasing lipid level regardless of lipid source. For diets fed during d 21 to 35 postweaning, there were interactions (P < 0.05) between lipid source and level for digestibility of DM, N, lipid, and energy and for DE, ME, and MEn of diets. The improved feed efficiency was, perhaps, partly attributable to the increase in ME content of the diets with added lipids. There were interactions (P < 0.05) between lipid source and level for efficiency of energy use for BW gain for diets fed during d 21 to 35. The efficiencies of use of DE, ME, and NE for BW gain were not affected in pigs fed diets containing increasing levels of soybean oil; however, there were linear increases in these response criteria for pigs fed diets containing increasing levels of tallow. These results indicate that the energy values of soybean oil from the 2012 NRC study used in formulating these diets were fairly accurate. [ABSTRACT FROM AUTHOR]

An experiment involving 854 crossbred pigs (20 replicate pens of 4 to 8 pigs per pen) was conducted at 8 experiment stations to determine the effects of acids in nursery pig diets and their inclusion amounts on growth performance using diets and weaning ages typical of those used in the United States commercial pork industry. Diets were formulated to have constant a ME and contain 1.45, 1.45, and 1.30% standardized ileal digestible Lys for phases 1, 2, and 3, respectively. The basal diets were supplemented with various types and concentrations of acid at the expense of corn {Zea mays). Treatment diets included 0% acid (control), 0.1 or 0.2% phosphoric acid, 1 or 2% organic acids, and 0.1% phosphoric acid plus 1% organic acids with or without an antibiotic. The organic acids consisted of 50% citric acid and 50% fumarie acid by weight. All but the final diet contained the antibiotic carbadox. All diets contained 3,000 mg of Zn/kg diet from zinc oxide during phases 1 and 2 and had limited acid buffering capacity, ranging from 142, 127, and 122 mEq/kg of feed for phases 1, 2, and 3, respectively. At each participating station, pigs were randomly allotted to dietary treatments on the basis of their initial BW. Sex and ancestry were equally distributed across the treatments. Results indicated that treatment effects on pig performance were observed in phases 1 and 2 but not in phase 3. In phase 1, ADG of pigs fed 0.2% phosphoric acid was greater than that of pigs fed the combination of acids with no antibiotic (P = 0.041). In phase 2, pigs fed treatments containing an antibiotic had a greater ADG than those fed the combination of acids without antibiotic (P < 0.05). Addition of acids to diets did not affect growth performance during any phase or the overall period. Over the 4-wk study, growth rate was slowest on the treatment without antibiotic, with specific differences that were often statistically significant (P < 0.05). In summary, under the conditions of this experiment, the acid treatments had no effect but the antibiotic improved growth performance. [ABSTRACT FROM AUTHOR]

The high cost of feed grains has led swine producers to seek alternative feedstuffs, such as distillers dried grains with solubles (DDGS). However, little is known about the effects of high levels of DDGS in swine diets on pork quality. The objective of this study was to evaluate belly processing and bacon, sausage, and loin quality of pigs fed high levels of DDGS. Sixty pigs averaging 34 kg BW were fed fortified com-soybean meal diets containing 0%, 15%, 30%, or 45% DDGS. At 120 kg BW, the pigs were humanely harvested and bellies, loins, and shoulders were removed from the left side of each carcass. Flex tests of bellies indicated that they became softer (linear, P < 0.03) as DDGS levels increased. The PUFA in backfat and belly fat increased linearly (P < 0.005), as did iodine values with increasing 0DDGS in the diet. Bellies were pumped to target 12% brine retention, cooked, and sliced at a commercial facility. Slicing yield was not affected by DDGS level fed. Fresh bacon slices were scored 1 to 6 with 1 representing no visible cracks in the fat and 6 representing a spider web-like shattering of the fat. Shatter scores decreased (linear, P < 0.001) with increasing dietary DDGS. Bratwurst-style sausage was produced by combining ground Boston butts and picnics to target 30% fat, blended with commercial seasonings, and stuffed into natural casings. Loose sausage was placed on trays, overwrapped with polyvinyl chloride wrap, and stored under constant, cool white florescent lighting (1,300 lx) at 4°C. Objective color values (L*, a*, and b*) were taken on loose-packaged sausage mix at 6 locations at the same time daily for 7 d. Sausage was also sampled for thiobarbituric acid reactive substances (TBARS) at the same time daily on d 0, 3, 5, and 7. Color scores of sausage were not consistently affected by DDGS level in the diet and the changes were slight. The TBARS in sausage from pigs fed the 30% and 45% DDGS diets increased to a greater extent from d 0 to 7 than in those fed the control or 15% DDGS diets. An 8-member, trained panel evaluated the sensory attributes of bacon slices, sausage, and loin chops. The DDGS resulted in a softer texture (P < 0.004) and increased juiciness (P < 0.04) in sausages, but no differences in sensory scores were found in bacon slices or loin chops. The results indicate that the softer bellies, greater concentrations of PUFA in carcass fat, and greater iodine values associated with feeding increased DDGS did not negatively affect slicing yield of cured bellies, quality of fresh bacon slices, or eating quality of bacon, sausage, or loin chops. [ABSTRACT FROM AUTHOR]

Dietary CLA has been reported to decrease backfat and increase marbling in pigs. Our objective was to determine whether the increase in marbling involved changes in intramuscular adipocyte number or size or both. Twenty barrows (53 kg) were penned in pairs and pens were randomly assigned to receive diets containing either 1% soybean oil (SBO) or CLA (60% CLA isomers) for 6 wk. Body weight and feed intake were determined weekly. At slaughter, loin samples were obtained and flash frozen for RNA extraction and real-time reverse-transcription PCR analysis of gene expression. After a 24-h chill, loin eye area and backfat depth were measured and subjective marbling and color scores were assigned. Loin, backfat, and belly fat samples were obtained for fatty acid analysis by gas chromatography. Loin samples were also frozen in ice-cold isopentane for histological analysis of intramuscular adipocytes. Dietary CLA did not affect BW or feed intake at any point (P > 0.10), nor did treatment groups differ in HCW (P = 0.417) or loin color (P = 0.500). The CLA-fed pigs did have less (P = 0.018) backfat and smaller (P = 0.047) loin eye area than SBO-fed pigs and had a trend for an increase (P = 0.069) in marbling score. Relative gene expression for markers of preadipocytes (preadipocyte factor 1; Pref-1), differentiating adipocytes (PPARγ), and mature adipocytes [fatty acid binding protein 4 (FABP4) and perilipin (PLIN)] were determined and normalized to the expression of acidic ribosomal phosphoprotein. No significant differences were detected, but the expression of PPARγ (P = 0.265), PLIN (P = 0.265), and FABP4 (P = 0.148) was numerically greater in CLA-fed pigs than in SBO-fed pigs. Loin samples were stained with Oil Red O to identify intramuscular adipocytes. The average cell area was increased (P = 0.030) in CLA-fed pigs. The cis-9,trans-11 and trans-10,cis-12 CLA isomers were incorporated (P = 0.006) into backfat and belly fat, but only trans-10,cis-12 CLA was increased in the loin (P = 0.004) of CLA-fed pigs. The proportion of SFA was increased (P = 0.006) by CLA in all tissues. These results indicate that the increase in marbling in pigs fed CLA may be related to increased intramuscular adipocyte size, and the combination of increased marbling and degree of saturation could improve the eating quality of CLA-fed pork. [ABSTRACT FROM AUTHOR]

An experiment involving 560 crossbred pigs (28 replications of 4 to 6 pigs per pen) was conducted at 9 research stations to assess the effects of dietary concentrations of corn distillers dried grains with solubles (DDGS) on pig performance and belly firmness. Fortified corn-soybean meal diets containing 0, 15, 30, or 45% DDGS were fed in 3 phases from 33 to 121 kg of BW. A common source of DDGS containing 90.1% DM, 26.3% CP, 0.96% Lys, 0.18% Trp, 9.4% crude fat, 34.6% NDF, 0.03% Ca, and 0.86% P was used at each station. Diets were formulated to contain 0.83, 0.70, and 0.58% standardized ileal digestible (SID) Lys during the 3 phases with diets changed at 60 and 91 kg of BW, respectively. The DDGS replaced corn and soybean meal, and up to 0.172% Lys and 0.041% Trp were added to maintain constant SID concentrations of Lys and Trp in each phase. At each station, 2 pigs from each pen in 2 replications were killed and a midline backfat core was obtained for fatty acid analysis and iodine value. In most instances, there were differences among stations (P < 0.01), but the station × treatment interactions were few. Body weight gain was linearly reduced in pigs fed the greater amounts of DDGS (0 to 45%) during phase I (950, 964, 921, and 920 g/d; P < 0.01) and over the entire experimental period (944, 953, 924, and 915 g/d; P = 0.03), but ADFI (2.73, 2.76, 2.68, and 2.70 kg) and G:F (347, 347, 345, and 341 g/kg) were not affected (P = 0.15 and P = 0.33, respectively) during the entire test. Backfat depth was reduced (linear, P < 0.02) by increasing amounts of DDGS (22.5, 22.7, 21.4, and 21.6 mm), but LM area (47.4, 47.4, 46.1, and 45.4 cm2) was not affected (P = 0.16) by treatments. Estimated carcass fat-free lean was 51.9, 52.2, 52.4, and 52.1% for 0 to 45% DDGS, respectively (linear, P = 0.06). Flex measures obtained at 6 stations indicated less firm bellies as dietary DDGS increased (lateral flex: 11.9, 8.6, 8.4, and 6.6 cm; linear, P < 0.001; vertical flex: 26.1, 27.4, 28.2, and 28.7 cm; linear, P < 0.003). Saturated and monounsaturated fatty acid concentrations in subcutaneous fat decreased linearly (P < 0.001) and PUFA concentrations increased linearly (P < 0.001) with increasing DDGS in the diet. Iodine values in inner (61.1, 68.2, 74.7, and 82.2) and outer (67.9, 73.6, 79.6, and 85.8) backfat increased linearly (P < 0.001) as DDGS in the diet increased. In this study, feeding diets with 30 or 45% DDGS did not have major effects on growth performance, but resulted in softer bellies. Regression analysis indicated that iodine values increased 4.3 units for every 10 percentage unit inclusion of DDGS in the diet. [ABSTRACT FROM AUTHOR]

The objective of this work was to determine if pigs of similar BW, but differing in 10th–rib hackfat thickness, would differ in their selection of dietary protein. The first experiment was conducted with guts and was designed in a 2 x 2 factorial arrangement with the main effects of body fat (lean vs. fat) and feeding program (single vs. choice). Crossbred guts (n = 32) with an initial BW of 79 kg were sorted into high (2.24 cm, fat) and low backfat (1.51 cm, lean; P < 0.001) groups based on real–time ultrasound scans at the 10th rib. Diets were 1) a low–protein corn–based diet supplemented with crystalline AA (8.5% CP, 0.58% Lys) and 2) a high–protein cornand soybean meal–based diet (22.7% CP, 1.275% Lys). During wk 1, all pigs were fed a 50:50 mix of the low–protein and high–protein diets. From d 7 to 28, one–half the pigs in the lean and fat groups were given a choice of lowand high–protein diets in separate feeders, whereas the others remained on the 50:50 mix. Initial differences in 10th–rib backfat thickness were maintained through d 28 (fat, 3.02 cm; lean, 2.42 cm; P < 0.001). Circulating leptin concentrations were greater in the fat pigs than in the lean pigs (3.84 vs. 3.35 ng/mL; P < 0.05). Average daily gain (1.06 kg/d) and ADFI (2.64 kg/d) were not different between treatment groups. However, the pattern of selection was different in the choice groups such that lean pigs consumed more (64.4%) of the high–protein diet than did fat pigs (35.6%, P < 0.01), resulting in a difference in the percentage of protein consumed (lean 16.9% CP; fat = 12.8% CP; P < 0.01). A second experiment of similar design, but with barrows (n = 32; initial BW 69 kg), was conducted. Barrows classified as fat had 2.33 cm of 10th–rib backfat as compared with 1.75 cm in the lean group (P < 0.01). The percentage of protein in the diet selected by the fat barrows was not different from that selected by the lean barrows (15.9 vs. 17.4%). The lack of difference in selection pattern in barrows may be accounted for by the relatively smaller difference in body composition between the fat and lean classifications in the barrows in the choice feeding program as compared with body composition of the gilts. These results demonstrate that gilts of similar BW, but differing in composition, likely have different nutrient requirements and diet selection patterns. Although allowing pigs to self–select did not alter growth rate, the results indicated that diet selection can be used to allow pigs to meet their individual nutrient requirements more closely. [ABSTRACT FROM AUTHOR]

Two experiments were conducted to determine the effects of anabolic implants on performance, changes in ultrasound measurements, carcass quality, cellularity of i.m. and s.c. adipose depots, and mRNA expression of acetyl CoA carboxylase (ACC), stearoyl CoA desaturase (SCD), and lipoprotein lipase (LPL) in i.m. adipose tissue of finished beef cattle. Angus heifers (experiment 1: n = 10; 411 kg of BW) and steers (experiment 2: n = 18; 279 kg of BW) were randomly allotted as control (C) or implanted with Synovex-Plus (SP) at d 0 and midway through the finishing period. The cattle were fed a high-concentrate diet and were weighed at approximately 28-d intervals. Heifers and steers were finished for 108 and 133 d, respectively. At slaughter, a section of the LM (sixth to ninth rib) was removed, and i.m. adipose tissue was dissected for mRNA analysis. Subcutaneous and i.m. adipose tissues also were collected for determination of cellularity. At 48 h postmortem, carcass data were collected, and a steak (12th rib) was removed for analysis of lipid and fatty acid composition. Body weight did not differ (P > 0.10) between treatments until after reimplanting of the heifers (d 55) or steers (d 73). Average daily gain was 36 and 16% faster (P ⩽ 0.01) for implanted heifers and steers, respectively, compared with their control counterparts. Implanting resulted in larger (P ⩽ 0.10) HCW and LM area for heifers and steers. However, implanting did not affect (P > 0.10) dressing percent, fat thickness, percentage of KPH, yield grade, or marbling score. Intramuscular lipid content and concentrations of major fatty acids did not differ (P > 0.10) between treatments. Percentage of SC adipocytes was greater at larger diameters (>150 μm), whereas the majority of i.m. adipocytes were at small to middle diameters (50 to 150 μm). The number of i.m. adipocytes per gram of tissue was greater (P < 0.05) for SP than C and also were greater (P < 0.05) than the number of s.c. adipocytes in SP heifers. In experiment 2, adipocytes per gram of tissue tended to be greater (P = 0.07) for SP than C and were greater (P < 0.01) for i.m. than s.c. In experiment 1, average cell diameter and volume did not differ (P > 0.10) between treatments and tissues, but in experiment 2 both cellularity traits were greater (P < 0.01) for s.c. than for i.m.. Implanting did not alter mRNA expression of ACC, SCD, or LPL in i.m. adipose tissue. This study shows that anabolic implants do not appear to have direct effects on i.m. lipid deposition. [ABSTRACT FROM AUTHOR]

Three experiments were conducted to evaluate pet food by-product (PFB) as a component of nursery starter diets and its effects on pig performance. The PFB used in these studies was a pelleted dog food that contained (as-fed basis) 21% CP, 1.25% total lysine, and 8.3% ether extract. In Exp. 1, 288 early-weaned pigs (5.2 kg at 14 d) were used to determine the effects of replacing animal protein and energy sources with PFB at 0, 10,30, and 50% (as-fed basis) inclusion levels in phase I (d 0 to 7 after weaning) and phase II (d 7 to 21 after weaning) diets. Phase I diets contained 27.5% whey, 18.75% soybean meal, 1.50% lysine, 0.90% Ca, and 0.80% P, with PFB substituted for corn, fat, plasma protein, fish meal, limestone, and dicalcium. phosphate. Phase II diets had a constant 10% whey, 1.35% lysine, and PFB was substituted for blood cells, a portion of the soybean meal, and other ingredients as in phase I diets. In phase I, growth performance by pigs fed PFB-containing diets was similar to that of the control diet. In phase II, ADG (linear; P < 0.05 and quadratic, P < 0.005), ADFI (linear and quadratic, P < 0.01), and G:F (quadratic, P < 0.01) were increased with increasing PFB inclusion. In Exp. 2, 80 weaned pigs (6.7 kg at 21 d) were fed a common phase I diet for 1 wk and used to further evaluate the effect of PFB in phase II diets (same as Exp 1; initial BW = 8.1 kg) on growth performance and apparent total tract nutrient digestibility. There were no differences in ADG, ADFI, or G:F across treatments. Dry matter and energy digestibility did not differ among diets; however, digestibilities of CP (P < 0.05) and the essential AA, arginine (P < 0.02), histidine (P < 0.01), lysine (P < 0.001), threonine (P < 0.01), and valine (P < 0.01), were greater as PFB was increased in the diet. In Exp. 3, the performance by pigs (n = 1 70; 5.5 kg; 21 d of age) fed diets with 0 or 30% PFB in both phases I and II was examined. Growth performance was similar in both diets. These studies demonstrate that pet food by-product can effectively be used as a partial replacement for animal protein sources and grain energy sources in the diets of young nursery pigs. [ABSTRACT FROM AUTHOR]

Crossbred harrows (n = 144; 80 kg) from four farrowing groups were phenotypically selected intc fat (FAT) and lean (LEAN) pens using ultrasound. The difference in 10th-rib fat depth between the LEAN and FAT groups was ≥0.5 cm. Within a farrowing group! pigs were assigned to pens (five pigs per pen and eight pens per phenotype) to equalize pen weight and fat depth. Pigs were fed a corn-soybean meal diet con taming 19% CP, 1.0% added animal/vegetable fat, and 1.1% lysine (as-fed basis). Half the pens received 10 ppm (as-fed basis) of ractopamine (RAG) during the 28-d finishing phase. At 7-d intervals, live weight and feed disappearance were recorded to calculate ADG, ADFI, and G:F, and 10th-rib fat depth and LM area were ultrasonically measured to calculate fat-free lean and fat and muscle accretion rates. During the first 7 d or feed, LEAN pigs fed RAG gained less (P < 0.05) thar FAT pigs fed RAG or LEAN and FAT pigs fed the control diet (RAG x phenotype; P = 0.02); however, RAC did not (F > 0.25) affect ADG after the second, third, and fourth weeks, or over the entire 28-d feeding period! Although wk-2 and -3 ADG were higher (P ≤ 0.03) in LEAN than in FAT pigs, phenotype did not (P = 0.08) affect overall ADG. Dietary RAG decreased (P ≤ 0.05) ADFI over the 28-d feeding trial, as well as in wk 2, 3, and 4, but intake was not (P > 0.20) affected by phenotype. Neither RAG nor phenotype affected (F > 0.10) G:F after 7 d on trial; however, RAG improved (P ≤ 0.04) wk-3, wk-4, and overall G:F. Lean pigs were more efficient (P ≤ 0.05) in wk 2 and 3 and over the duration of the trial than FAT pigs. Ultrasound LM accretion (ULA) was not (P ≥ 0.10) affected by RAG; however, LEAN pigs had greater (P ≤ 0.02) ULA in wk 2 and 4 than FAT pigs. Although fat depth was lower (P < 0.01) in RAC-fed pigs than pigs fed the control diet, ultrasound fat accretion rate indicated that RAG-pigs deposited less (P = 0.04) fat only during wk 4. In addition, calculated fat-free lean (using ultrasound body fat, ULA, and BW) was increased (P < 0.05) in RAG pigs after 3 and 4 wk of supplementation. In conclusion, RAC enhanced the performance of finishing swine through decreased ADFI and increased G:F, whereas carcass lean was enhanced through decreases in carcass fat and increases in carcass muscling. [ABSTRACT FROM AUTHOR]

Three experiments were conducted to evaluate pet food-grade poultry by-product meal (PBM) as a replacement protein source for fish meal (FM), blood meal (BM), and spray-dried plasma protein (SDPP) in weanling pig diets. In the first study, 200 crossbred pigs (initial BW = 6.5 kg) were weaned (21 d) and randomly allotted to one of four dietary treatments, which included a control and three test diets where PBM was substituted for FM, blood products, or both. Experimental diets were fed during Phase I (d 0 to 5 postweaning) and Phase II (d 5 to 19), and a common Phase III diet was fed from d 19 to 26. Overall (d 0 to 26), there was no difference in performance of pigs fed PBM in place of the other ingredients. However, during Phase I, BW (P < 0.05), ADG (P < 0.02), and intake (P < 0.001) in pigs fed diets containing SDPP were greater than those fed diets with PBM. In Exp. 2, the performance of pigs (n = 100, initial BW = 6.5 kg) fed diets containing 20% PBM (asfed basis, replacing SDPP, BM, FM, and a portion of the soybean meal) in all phases of the nursery diet was compared with a group fed conventional diets without PBM. There were no differences in overall performance (d 0 to 26); however, ADG (P < 0.10) and feed intake were higher (P lt; 0.01) for pigs fed the conventional diet than for pigs fed the 20% PBM diet during Phase I (d 0 to 5). Experiment 3 was a slope-ratio assay to determine the ability of PBM to replace SDPP. A total of 320 pigs (initial BW = 7.32 kg) was weaned (21 d) and allotted to five treatment groups in three trials in a blocked design with product (SDPP or PBM) as the first factor, and lysine level (1.08, 1.28, 1.49%; as-fed basis) as the second factor. Growth rate increased with increasing lysine (P < 0.05), regardless of the source. These results indicate that PBM can be used in nursery diets in place of blood meal and fish meal without affecting performance. Furthermore, although feeding PBM in Phase I diets was not equivalent to SDPP during the first week, there was no overall difference in performance at the end of the nursery phase. [ABSTRACT FROM AUTHOR]

Presents information on a study which examined the dietary dose responsiveness of conjugated linoleic acid addition relative to the fatty acid profile of edible bean tissue in grower pigs treated with or without porcine somatotropin. Materials and methods; Results and discussion.

The study objective was to assess the contribution of fat source and vitamin E (VE) supplementation on growth performance, antioxidant status, and fatty acid profile in the liver of pigs at heavy slaughter weight (148.09 ±1.64 kg). A total of 72 individually-fed pigs (36 barrows, 36 gilts; 28.55 ±1.16 kg) were randomly assigned to 12 dietary treatments in a 2 × 6 factorial arrangement. Fat treatments were tallow and corn-oil. The VE treatments included four levels of α-tocopheryl-acetate (ATA; 11, 40, 100, and 200 ppm) and two levels of mixed tocopherols (primarily γ-tocopherol; 40 and 100 ppm). Liver samples were collected at slaughter. Data analysis were performed by ANOVA using GLM in SAS. No effect of dietary fat sources, isoforms of VE, and levels of γ-tocopherol were detected on growth performance or liver antioxidant status (GSH, GSSG, SOD, and MDA). Increasing dietary ATA linearly increased overall ADG (0.98, 1.02, 1.02, and 1.08 kg/day; P = 0.02) from 28 to 150 kg; overall ADG of pigs fed γ-tocopherol-diets was 1.07 and 1.04 kg/day, respectively. An interaction between fat sources and ATA was observed on cumulative ADG during Phase1-3 (28-100 kg; P = 0.04) and Phase1-4 (28-125 kg; P = 0.03) wherein pigs fed corn-oil-diet, but not tallow-diet, had increased ADG with increased dietary ATA. Increasing dietary ATA quadratically increased SOD activity (P < 0.05; highest at 100 ppm), and quadratically decreased MDA content (P < 0.05; lowest at 40 ppm) in the liver. Liver fatty acid profile was affected by fat source (P < 0.05) but not VE treatment, pigs fed corn-oil-diets had less SFA (34.23 vs. 35.45%; P = 0.02) and MUFA (11.98 vs. 18.38%; P < 0.0001), but more PUFA (49.14 vs. 40.78%; P < 0.0001) than pigs fed tallow-diets in the liver. Beneficial effects of dietary VE supplementation were observed on growth performance and antioxidant status of pigs under conditions of this study. [ABSTRACT FROM AUTHOR]

There are limited data on the effects of exogenous lipase on digestibility and growth performance in weanling pigs. The objective of this study was to investigate the effects of lipase and the interaction with copper in the diet. The study was conducted in a 2 x 2 factorial arrangement to examine the effects of lipase (Shenzhen Leveking Animal Nutrition; 0 vs 1,000 U/kg) and copper (NRC vs 250 ppm added from copper sulfate). A total of 192 pigs were used in the study, which was conducted in 2 trials of 24 pens each (4 pigs per pen). Pigs were weaned at 21 d (Initial Weight = 5.9 ± 0.3 kg) and allotted to pens based on weight, sex, and litter). Dietary treatments were randomly assigned to pens within weight blocks (Control diet (C), C+ lipase, C+ Cu and C+ lipase + Cu). Diets were formulated to meet or exceed all the nutrient requirements based on the 2012 NRC and fed in 2 phases (d 0 to 14 and d 14 to 28). Titanium dioxide (0.3%) was used as digestibility marker and fecal samples were collected at the end of each phase. Growth performance (ADG, ADFI, and G:F) data were obtained on d 7, 14, 21 and 28 post-weaning and analyzed using PROC GLM. There were no significant lipase x Cu interactions on growth performance. Overall, there was a significant main effect of Cu on BW (16.4 vs 18.1 kg, P< 0.001), ADG (373 vs 432 g/d, P <0.001), ADFI (497 vs 535 g/d, P < 0.020), and G:F (0.75 vs 0.81), P < 0.001). There was a trend for lipase to improve ADG from d 0 to 14 (237 vs 254, P < 0.200) and overall G: F (0.77 vs 0.79, P<0.100). Copper supplementation improved digestibility of fat in phase 1 and N and P digestibility in both phases. There was no consistent effect of lipase or interaction of lipase x copper on nutrient digestibility. In conclusion, Cu supplementation improved growth performance and nutrient digestibility. There was a trend for exogenous lipase to improve the growth performance, but no consistent effect on digestibility and no evidence of a copper x lipase interaction. [ABSTRACT FROM AUTHOR]

The study objective was to assess the contribution of fat source and vitamin E supplementation on growth, carcass traits, and pork quality at a heavy slaughter weight (149.38 ± 1.56 kg). A total of 64 individually-fed pigs (32 barrows, 32 gilts; 28.41 ± 0.83 kg) were randomly assigned to 8 dietary treatments in a 4 × 2 factorial arrangement. Fat treatments included corn-starch (CS), tallow (TW), corn oil (CO) and coconut oil (CN); the corn-starch diet was formulated to equalize presumed daily intake of non-fat ingredients to the 5% fat added diets. Vitamin E (VE) supplementation was at 11 and 200 IU/kg. When slaughtered at 150 kg, carcass traits and primal cuts were measured, plasma and loin muscles were collected. Data were analyzed for main effects and interaction as a complete block factorial arrangement. No interactions were observed (P > 0.10) except plasma VE concentration (P = 0.0077). Pigs fed with CO diet had highest plasma VE concentration (CS 1.44, TW 2.06, CO 2.46, and CN 1.79 ppm; P < 0.05) when supplemented with 11 IU/kg VE. While pigs fed with CN and TW diet had higher plasma VE concentration (CS 4.35, TW 5.63, CO 4.43, and CN 5.71 ppm; P < 0.05) when supplemented with 200 IU/kg VE. No difference in average daily gain, carcass traits, subjective meat quality, and yield of boston-butt, picnic-shoulder, and spare-rib were observed (P > 0.10). Improving VE level from 11 to 200 IU/kg improved ham yield (12.28 vs 12.95 kg; P < 0.05) and plasma VE concentration (1.94 vs 5.03 ppm; P < 0.0001), while decreased belly depth (55.06 vs 52.09 mm; P < 0.05). Pigs from CS group had greater area of loin-muscle than CN and CO group (CS 64.07, TW 60.40. CO 56.65 and CN 58.69 cm2; P < 0.05). Belly depth for pigs from CN group was greater than the other fat treatments (CS 53.45, TW 51.80, CO 50.33, and CN 58.72 cm; P < 0.05). The pigs fed with CN diet had the highest lateral flex test (CS 19.53, TW 20.18, CO 11.25, and CN 31.84 cm; P < 0.05) and lowest vertical flex test (CS 26.67, TW 25.31, CO 32.27, and CN 16.31 cm; P < 0.05). Under conditions of this study, both dietary fat source and VE supplementation affected the response measures. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the amount training necessary for reliable data to be obtained. Thirty-one True Choice Genetics pigs (CG32 x EB5 (9 females, 7 males) and CG32 x EBX (8 females, 7 males) weighing 68 kg were used to determine changes in gait due to training. Pigs were individually walked across a 7.5 m pressure mat (GAIT4Dog®) every day on D1-D5 and then again on D8. Training was conducted using a sorting paddle as negative reinforcement (removing pressure) and positive punishment (adding pressure). Sessions were recorded on D1, D2, D4, and D8. Pigs walked across the mat for either 6 usable repetitions or for a maximum of 20 minutes. Stance time, swing time, stride length, percent stance, gait cycle, and velocity were determined for each day. All data were analyzed using SAS 9.4 PROC MIXED repeated measures model. There was a significant increase in velocity from D1 to D4 and a decrease on D8 (P < 0.001), which resulted in a decrease from D1 to D4 and an increase on D8 in swing time (P < 0.001), stance time (P < 0.001), cycle time (P < 0.001), and percent stance (P < 0.001). There were differences between females and males for self-selected velocity (P < 0.001), and stride length (P < 0.001). Females had a decreased cycle time (P < 0.001) and percent stance (P < 0.001). Differences between the EB5 and EBX sire lines were seen for rear swing (P < 0.001), front stance (P < 0.01), cycle time (front P < 0.02), and percent stance (front P < 0.01). Changes due to training reflect the loss of novelty to the mat due to repeat exposure. Differences due to sex and genetic line may be related to conformational differences. Velocity (cm/s) D1 D4 D8 Female Male EB5 EBX 180.3 196.81 188.67 197.35 182.75 187.75 192.35 Swing (s) Front 0.23 0.22 0.22 0.23 0.22 0.23 0.23 Rear 0.26 0.25 0.25 0.25 0.25 0.26 0.25 Stance (s) Front 0.26 0.22 0.24 0.22 0.25 0.24 0.23 Rear 0.23 0.19 0.21 0.19 0.22 0.21 0.21 Stride Length (cm) Front 83.49 84.59 84.24 85.84 82.71 83.77 84.78 Rear 83.28 84.36 84.01 85.65 82.46 83.59 84.52 Percent Stance (%) Front 50.92 49.38 49.92 48.48 51.84 50.65 49.67 Rear 45.69 43.11 44.38 42.41 45.87 43.65 44.63 Least square means of gait parameters for days, sex and sire lines [ABSTRACT FROM AUTHOR]

The study objective was to assess the contribution of fat source and vitamin E (VE) supplementation on tissue tocopherol concentration, antioxidant status, and fatty acid composition in the backfat of pigs at heavy slaughter weight (149.38 ±1.56 kg). A total of 64 individually-fed pigs (32 barrows, 32 gilts; 28.41 ±0.83 kg) were randomly assigned to 8 dietary treatments in a 4 × 2 factorial arrangement. Fat treatments included corn-starch (CS), tallow (TW), corn oil (CO) and coconut oil (CN). VE supplementation levels were 11 and 200 IU/kg. Loin muscle, backfat, and liver samples were collected at slaughter. Data analysis were performed by ANOVA using GLM in SAS. No interactions between dietary fat source and VE supplementation were observed. Increasing dietary VE level from 11 to 200 IU/kg increased (P < 0.001) the tocopherol concentration in both liver (4.73 vs. 21.06 ppm wet liver) and loin muscle (1.25 vs. 2.67 ppm wet muscle). Pigs from the CO group had higher liver SOD activity (P < 0.05) than the other treatments (CS 22.51, TW 22.67, CO 24.40, and CN 20.92 U/mg protein). Pigs from the CN group had the highest (P < 0.05) total saturated fatty acid content (CS 44.33, TW 40.33, CO 36.29, and CN 51.70%), but the lowest (P < 0.05) total polyunsaturated fatty acid content (CS 9.26, TW 9.80, CO 25.41, and CN 8.75%) and iodine value (CS 56.61, TW 60.66, CO 77.83, and CN 49.90) in the backfat. Pigs from the TW group had the highest (P < 0.05) total monounsaturated fatty acid content (CS 46.40, TW 49.87, CO 38.30, and CN 39.56%) in the backfat. Under conditions of this study, a higher level of VE supplementation increased liver and muscle tocopherol concentrations whereas dietary fat sources altered liver antioxidant activity and fatty acid composition in the backfat. [ABSTRACT FROM AUTHOR]

Seventy True Choice Genetics (CG32) gilts were allotted to two treatments at weaning (28-35 d) and were fed experimental diets from nursery through their second parity. Treatments were a control diet and the control diet plus a mineral amino acid complex (MAAC) (Avalia®Sow fed at 750 g/metric ton). Gilts were grown under standard conditions and then followed for their first two parities. Litter size, piglet birthweight and piglet weaning weight were recorded for each parity. The gilt's gait was captured while walked through a dog bone track (7.5 m long) using a gait mat (GAIT4Dog®) pre-parturition (45-70 days pregnant) for both parities. Each gilt was walked until 6 usable repetitions were acquired. Data were analyzed for stance, swing, velocity, stride length, percent stance, cycle time and total pressure index. Claws and dewclaws were measured and recorded after walking. Data were analyzed in SAS 9.4 PROC MIXED repeated measures model. There were not differences in litter performance parameters the first two parities. Velocity increased in the treated sows the second parity (P < 0.03; 98.32, 107.17 cm/s, control and treated, respectively). Cycle time decreased in the treated sows for the second parity for both the front and rear legs (front P < 0.007; 1.00, 0.94 s; rear P < 0.002; 1.02, 0.93 s, control and treated respectively). Swing time second parity was decreased in the treated animals compared to the controls for both the front and rear legs (front P < 0.002; 0.33, 0.31 s; rear P < 0.001; 0.38, 0.36 s; control and treated respectively). Stance time decreased in the second parity for treated sows compared to control both the front and rear legs (front P < 0.003; 0.69, 0.62 s; rear P < 0.004; 0.64, 0.58 s; control and treated respectively). For the second parity percent stance decreased in the treated sows for the front legs (front P < 0.04; 66.58, 65.34 %) but was not significant for the rear legs. The total pressure index indicated that treated sows placed more weight on rear legs then control sows second parity (front P < 0.02; 58.11, 57.44%; rear P < 0.02; 41.90, 42.56%, control and treated respectively). There were no significant differences for claw lengths or sow productivity between the control and treatment. These differences provide evidence that adding MAAC impacts locomotion by improving gait quality in sows as they age. [ABSTRACT FROM AUTHOR]

The objective of this study was to isolate measurements in young pigs and monitor changes as the pigs grew. These values might be able to help pinpoint lameness prone animals and allow for their removal from the herd. Twenty-seven True Choice Genetics pigs (CG32xEB5 (9 females, 6 males) and G32 x EBX (6 females, 5 males) were randomly selected prior to 23 kg to evaluate changes in gait as pigs grow. Pigs were individually walked across a 7.5 m pressure mat (GAIT4Dog®) at 23, 45, 68, 91, 113 and 136 kg for 6 repetitions at each weight. Stance time, swing time, stride length, percent stance, gait cycle, and velocity were recorded and analyzed using SAS 9.4 PROC MIXED repeated measures model. Velocity decreased as pigs grew, (P < 0.03). There was an increase from 23 to 136 kg in cycle time for both the front and back legs (P < 0.0011). Stride length (P < 0.001), swing time (P < 0.001) and stance time (P < 0.001) both increased as the animals aged. Percent stance for both front and rear legs increased as the animal aged (P < 0.001). Compared to males, females had an increased velocity (P < 0.001), decreased cycle time (P < 0.001), increased stride length (P < 0.001), decreased stance time (P < 0.001) and decreased percent stance (P < 0.001). Compared to the EB5 sired pigs, the EBX sired pigs had increased velocity (P < 0.002), increased cycle time (front P < 0.03; rear P < 0.06), increased stride length (P < 0.001), increased swing time (P < 0.001), and decreased percent stance (front P< 0.01; rear P < 0.001). These data indicate that the gait of pigs changes with growth and there are differences in the gait due to sex and sire line. Velocity (cm/s) 23 kg 136 kg Female Male EB5 EBX 184.89 180.93 192.75 178.83 181.56 190.03 Front Swing (s) 0.21 0.23 0.23 0.23 0.22 0.23 Stance (s) 0.16 0.29 0.22 0.25 0.24 0.24 Stride Length (cm) 67.67 91.60 84.29 81.70 80.47 85.52 Percent Stance (%) 43.37 54.64 48.48 50.63 50.00 49.11 Rear Swing (s) 0.23 0.26 0.25 0.25 0.24 0.26 Stance (s) 0.14 0.27 0.20 0.22 0.22 0.21 Stride Length (cm) 67.66 91.14 84.01 81.48 80.28 85.22 Percent Stance (%) 37.14 49.78 44.06 45.28 45.83 43.50 Least square means of gait parameters for beginning and end weights, sex and sire lines [ABSTRACT FROM AUTHOR]

Databases comparing total amino acid (AA) profiles and standardized ileal AA digestibility (SID) values of 20 feedstuff's commonly fed to pigs from two sources, Evonik (Kennesaw. GA) and the Nutrient Requirements of Swine published by the National Research Council (NRC; Washington, DC) were used to observe AA concentration effects on digestibility values. Both databases reported SID swine values. The number of AA values depends on the ingredient. The 20 feed ingredients were compared from each database and were analyzed using PROC CORR and GLM procedures of SAS (version 9.4; SAS Inst. Inc., Cary, NC). When both databases were compared in their entirety, there was a positive correlation of 0.362 for the Evonik database and 0.349 for the NRC database (P < 0.0001) with increasing total amino acids vs. SID digestibility. There were also differences between feed ingredients in the Evonik and NRC databases (P < 0.0001). There were differences in SID of animal and plant sources (P < 0.001). When only essential AA were compared, there were positive correlations of 0.353 and 0.455 for the Evonik and NRC databases, respectively (P < 0.0001), of total AA to SID digestibility. There was a trend for differences between plant and animal feed ingredients when essential AA were being compared (P < 0.10). Four essential AA were analyzed separately across feedstuff: Lys, Met, Trp, and Thr. Lysine in both databases had a correlation with increasing total lysine and increasing SID (0.556 and 0.618; P < 0.01) forthe Evonik and NRC databases, respectively. Methionine also had increasing SID with total AA with a correlation of 0.577 and 0.666 (P < 0.01) for the Evonik and NRC databases, respectively. Methionine also had differences in SID in plant vs. animal sources (P < 0.05). Tryptophan had a correlation of 0.435 (P < 0.06) for the Evonik database, while the NRC database had a correlation for Trp of 0.544 (P < 0.01) of increasing SID with increasing total Trp. Threonine had a correlation of 0.390 (P < 0.09) for the Evonik database and 0.505 (P < 0.05) for the NRC database of total Thr vs. Thr SID digestibility. From this data, a predictor of AA digestibility is AA concentration of the feedstuff. The digestibility of AA in the feedstuff should be a property of the feed ingredient and not the concentration of AA in the feed ingredient. Differences in databases will change the cost of diet formulation. The database that is used to formulate amino acid profiles could affect the performance of the pig because of differences between databases. [ABSTRACT FROM AUTHOR]

Wheat gluten (WG) is a high-protein ingredient (75% CP) that is commonly used in pet food and milk replacers, but not commonly used in swine diets. Two studies were conducted to determine the effect of WG on growth performance of weaned pigs, and to determine if WG is an alternative for high cost ingredients such as fish meal (FM) and plasma protein (PP) in a phase 1 diet. Pigs were weaned at approximately 21 d and blocked according to weight. Body weight gain and feed disappearance were measured weekly in each experiment. All diets were formulated to meet or exceed the 2012 NRC standards. Exp. 1 utilized 36 pigs (IW = 6.2 + 0.2 kg, 12 pens, 3 pigs/ pen). There were 3 dietary treatments: 1) 0% WG, 2) 5% WG, and 3) 10% WG. WG was added at the expense of corn and soybean meal. Diets were fed for 14 d postweaning, followed by a common diet for an additional 14 d. There were 4 dietary treatments (IW = 6.4 + 0.4 kg, 32 pens, 3 pigs/pen) in Exp. 2: a control diet (5% FM and 5% PP), 5% WG in place of FM, 5% WG in place of PP, and 5% WG replacing 1/2 of each FM and PP. Test diets were fed for 14 d, followed by a common diet for an additional 7 d. In Exp. 1, ADG in phase 1 (0-14 d) for pigs fed 5% WG (398 g/d) was greater than pigs fed 0 (3 31 g/d) or 10% WG (300 g/d, quadratic, P < 0.01). These differences were maintained when pigs were fed a common diet 14-28 d (ADG: 660, 720, and 633 g/d for 0, 5, and 10% WG respectively, quadratic, P < 0.01). In Exp. 2, pigs fed the diet with no PP had lower ADG than other treatments (ADG: 435, 423, 396, and 440 g/d for Control, WG for FM, WG for PP and WG for 1/2 FM and PP, P < 0.20). Pigs fed the diet with WG replacing 1/2 of the FM and PP had improved G:F (0.84, 0.84,0.83,0.89 for Control, WG for FM, WG for PP, and WG for 1/2 FM and PP, P < 0.02). In Exp. 2, it was concluded that WG can substitute for FM, but not PP. Results indicate that WG fed at 5% of the diet may be a cost-effective, alternative protein source in phase 1 diets. [ABSTRACT FROM AUTHOR]

Lameness is a major cause of culling in sow herds. The objective of this study was to ascertain kinematic adaptations following corrective claw trimming of sows. In this study, 52 sows individually walked a semicircular (4 m diameter) and then a straight chute (0.6 m wide) system before and 1 and 48 h after trimming (PRE, POST1, and POST48, respectively). Sows were simultaneously video recorded as they passed through the straight chute and moved perpendicularly between 2 synchronized cameras. The straight chute consisted of 2.4 m each of prerecording and recording distance followed by 1.7 m postrecording distance. Sows were electronically timed walking through the recording frame, which each sow repeated until 5 useable repetitions, defined as falling within a 10% deviation of the mean time were achieved After the pretrimming videography, claws were correctively trimmed to approximately 5.5 cm away from coronary band, and then sows were video recorded at 1 and 48 h after trimming. Video recordings were analyzed using a 2-dimensional kinematic software program (Kinovea) to assess duration of swing, stance, breakover, stride length, and 3-limb support phase. Stride duration and velocity, swing:stance ratio, and both stance and breakover as percentages of stride duration were calculated. Data were analyzed using PROC MIXED of SAS (P < 0.05 significant; SAS Inst. Inc., Cary, NC). Analysis revealed a decrease in overall stride duration (1.04, 1.02, and 0.98 s in the front and 1.14, 1.11, and 1.07 s in the rear for PRE, POST1, and POST48, respectively; P < 0.0001) and breakover (0.12, 0.11, and 0.10 s in the front and 0.14, 0.12, and 0.11 s in the rear for PRE, POST1, and POST48, respectively; P < 0.0001). Stride length decreased in the front limbs (106.5, 103.7, and 104.5 cm for PRE, POST1, and POST48, respectively; P < 0.05) and velocity increased (104.8, 105.1, and 109.7 cm/s in the front and 93.2, 95.2, and 101.3 cm/s in the rear for PRE, POST1, and POST48, respectively; P < 0.0001). The three-limb support phase decreased (47, 46, and 42% in the front and 49, 46, and 42% in the rear for PRE, POST1, and POST48, respectively; P < 0.0001). Breakover as a percent of stride duration decreased (12, 11, and 10% in die front and 12, 11, and 10% in the rear for PRE, POST1, and POST48, respectively; P < 0.001). This data supports the practice of claw trimming to improve gait efficiency of the sow, which may influence sow longevity and culling rate. [ABSTRACT FROM AUTHOR]

The objective of this study was to determine the effects of feeding a diet containing n-3 fatty acids during late gestation and/or lactation on sow milk composition. The study was designed as a 2 x 2 factorial arrangement with main effects of feeding n-3 fatty acids in the gestation diet and/or lactation diet. Diets were corn-SBM based diets such that the gestation diet (G) was calculated to contain approximately 3290 kcal ME, 13% CP and, 0.78% lysine, while the lactation diet (L) was calculated to contain 3242 kcal ME, 17.5% CP and, 1.15% lysine. Omega-3 fatty acids, supplemented in the form of an encapsulated product (Fertilium®, United Feeds, Sheridan, IN), added to the G or L diet resulted in a shift of the n-6/n-3 ratio from approximately 20 in the control to 13 in the n-3 G diets and 13 to 10, respectively, in the L diets. Fertilium® is 17.5% fat, with about 15% of that as EPA and DHA, and was added at only 1.5% of the diet. Sows (n=44) were allocated by parity to either the control or n-3 diet at approximately d 60 of gestation. Sows were moved to the farrowing barn on d 110 and switched to the L diet, with half of the sows in each dietary treatment maintained on the same diet and half switched to the other diet (Control or Omega-3). Litters were weaned at an average of 21 d and sows were maintained on their respective diets through re-breeding. Milk samples were obtained from each sow within 24 h of farrowing, at d 7, and at weaning. The addition of n-3 fatty acids increased the total n-3 percent of milk from O/O sows (1.35%) as compared to C/C sows (1.12%, p<0.0001). While the percent of total n-6 in the milk did not change, the change in n-3 significantly altered the n-6/n-3 ratio (17.49 for C/C to 14.56 for O/O, p< 0.0001). There was a diet effect on both EPA and DHA concentrations. Addition of n-3 to the L diet increased the concentrations of EPA (0.09% in O/O vs. 0.03% in C/C, p<0.0001) and DHA (0.14% vs. 0.03% in O/O and C/C respectively, p<0.0001) regardless of which G diet the sow consumed. These results demonstrate that small additions of n-3 fatty acids to the maternal diet can significantly alter the milk consumed by progeny. [ABSTRACT FROM AUTHOR]

Numerous factors are involved in the regulation of feed intake in growing animals. The focus of this presentation is on the roles that body composition or composition of gain play in energy and amino acid requirements in nonruminants. When fed a single diet, energy is the primary determinant of intake. However, when animals are allowed to select between diets that vary in macronutrient nutrient content, they are able to self-select a diet that optimizes growth. This has been observed with diets that vary not only in crude protein, but in individual essential amino acids. Examples of this ability include studies that examine differences in selection patterns in response to 1) age-associated, 2) repartitioning agent induced or 3) genetic changes in composition of gain. In the case of repartitioning agents, growing pigs treated with somatotropin have changes in the rates of protein and lipid accretion that alter the energy and protein (amino acid) requirements and ultimately affect selection patterns and total feed intake. Similarly, the selection pattern between high and low protein diets differs in pigs with different levels of fatness. The mechanisms involved in the ability to monitor lipid and protein accretion rates in the periphery and to distinguish subtle differences between diets are not clear, particularly in livestock. Research in rodent models suggests that protein accretion likely affects circulating amino acid levels which in turn alter neurotransmitters that are monitored centrally. Leptin or other factors from adipose tissue may be the signal used to monitor rates of lipid accretion. The ability to distinguish differences in incoming nutrients, particularly amino acids is likely through the liver. A better understanding of the mechanisms that tie composition of gain to diet selection would contribute to design of feeding systems that meet the nutrient requirements of individual animals under group housing conditions. [ABSTRACT FROM AUTHOR]

A multi-state (WI, GA, MI, and NE) experiment was conducted by the NCCC-42 Swine Nutrition Committee to evaluate a vitamin trace mineral premix (VMP). VMP was formulated to provide minimal quantities of vitamins and trace minerals needed to complement nutrients supplied by ingredients typical in US swine diets. In the current trial (18 to 23 d weaned pigs), VMP was added to a complex starter diet to supply either 0, 1X or 3X supplemental vitamin concentrations where X equals quantities of vitamins to meet minimum requirements if nutrients from other ingredients are considered. Because of limited data on bioavailability of several B vitamins (biotin, choline, folate, pyrodixine, and thiamin) in feed ingredients, a B vitamin premix (+B) was formulated to supply these vitamins at minimum concentrations. The +B was added to diets with either 1X or 3X (1X+B and 3X+3XB) VMP. A sixth treatment (St) involved standard premixes used at each respective station. Trace minerals were constant in all diets except St. Pigs were allowed continuous access to assigned meal diets and water throughout a 28-d trial. Differences among stations were detected (P < 0.05), but no interactions among stations and diets were detected for ADG or ADfiresponses. Pigs fed diets with no VMP (0X) gained less and consumed less feed than pigs in other groups (P < 0.05). No advantages in ADG nor ADfiwere detected in pigs fed diets with additional 3X VMP or VMP+B at 1X or 3X levels. Pigs fed St diets tended (P < 0.10) to gain faster and consumed more feed (P < 0.05) than pigs fed VMP diets at 1X or 3X. In conclusion, 1X VMP allowed adequate growth over a 4-wk nursery trial. Additions of higher quantities of VMP or supplemental B vitamins did not improve growth. [ABSTRACT FROM AUTHOR]

The objective of this study was to determine if there were sustained benefits of high levels of phytase (12,500 U/kg) in nursery /grower phase on subsequent performance. At an initial weight of 20 kg, 80 pigs were assigned to one of 5 dietary treatment groups in pens of 4 pigs (2 barrows, 2 gilts) each. There were three dietary phases fed: 20-45 kg, 45-90 kg and 90-130 kg during the 16 wk study. Diet 1 was the positive control and contained 0.35, 0.30 and 0.25% avail. P in the 3 phases, respectively. Diets 2-5 had no inorganic P added and contained 0.13, 0.10 and 0.10% avail. P. Diet 2 was the negative control diet. Diet 3 was supplemented with 500 U/kg phytase (Quantum 2500D™) in all phases; Diet 4 with 12,500 U in phase 1 and 500 U in phase 2 and 3; diet 5 had 12,500 U in phase 1 and 2 and 500 U/kg in phase 3. In phase 1, addition of 500 U/kg phytase (711g/d) increased growth over the negative control (650 g/d), while 12,500 U (863 g/d) normalized gain to that of the positive control (873 g/d). Overall, growth rate was greater in pigs that were fed high levels of phytase early and then lower levels than in those fed 500 U for the entire study. Phytase addition improved phosphorous digestibility in each phase. There was no effect of phytase on carcass characteristics when adjusted for BW. Metatarsal bone weight was reduced with the low P diet and increased with 500 U phytase. Bone weight was not different from the positive control in pigs that were fed 12,500 U phytase in phase 1 or 2. Percent ash and bone strength were reduced on the low P diet and restored with addition of any level of phytase. These results suggest that the benefits of feeding high levels of phytase in the nursery and or grower phase are sustained in the finisher phase. [ABSTRACT FROM AUTHOR]

The objective of this work was to determine if pigs of similar BW, but differing in 10th–rib hackfat thickness, would differ in their selection of dietary protein. The first experiment was conducted with guts and was designed in a 2 x 2 factorial arrangement with the main effects of body fat (lean vs. fat) and feeding program (single vs. choice). Crossbred guts (n = 32) with an initial BW of 79 kg were sorted into high (2.24 cm, fat) and low backfat (1.51 cm, lean; P < 0.001) groups based on real–time ultrasound scans at the 10th rib. Diets were 1) a low–protein corn–based diet supplemented with crystalline AA (8.5% CP, 0.58% Lys) and 2) a high–protein cornand soybean meal–based diet (22.7% CP, 1.275% Lys). During wk 1, all pigs were fed a 50:50 mix of the low–protein and high–protein diets. From d 7 to 28, one–half the pigs in the lean and fat groups were given a choice of lowand high–protein diets in separate feeders, whereas the others remained on the 50:50 mix. Initial differences in 10th–rib backfat thickness were maintained through d 28 (fat, 3.02 cm; lean, 2.42 cm; P < 0.001). Circulating leptin concentrations were greater in the fat pigs than in the lean pigs (3.84 vs. 3.35 ng/mL; P < 0.05). Average daily gain (1.06 kg/d) and ADFI (2.64 kg/d) were not different between treatment groups. However, the pattern of selection was different in the choice groups such that lean pigs consumed more (64.4%) of the high–protein diet than did fat pigs (35.6%, P < 0.01), resulting in a difference in the percentage of protein consumed (lean 16.9% CP; fat = 12.8% CP; P < 0.01). A second experiment of similar design, but with barrows (n = 32; initial BW 69 kg), was conducted. Barrows classified as fat had 2.33 cm of 10th–rib backfat as compared with 1.75 cm in the lean group (P < 0.01). The percentage of protein in the diet selected by the fat barrows was not different from that selected by the lean barrows (15.9 vs. 17.4%). The lack of difference in selection pattern in barrows may be accounted for by the relatively smaller difference in body composition between the fat and lean classifications in the barrows in the choice feeding program as compared with body composition of the gilts. These results demonstrate that gilts of similar BW, but differing in composition, likely have different nutrient requirements and diet selection patterns. Although allowing pigs to self–select did not alter growth rate, the results indicated that diet selection can be used to allow pigs to meet their individual nutrient requirements more closely. [ABSTRACT FROM AUTHOR]