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Ideal conditioned sows are desired because they maximize herd performance, improve female well-being, and optimize financial outcomes. Sow productivity has increased, and body composition of females has changed, with sows being leaner and having less adipose tissue compared with their predecessors. Our objective was to determine the relationship between sow caliper measurements with sow reproductive performance and longevity in the herd. Data collected in four different production systems located in the US and Brazil were used, with 3,083, 356, 7,456, and 26,773 individual PIC Camborough observations represented within each of these databases. Caliper measurements were collected at due to farrow and weaned sows and were recorded in units, standardized to an ideal range of 12 to 15 units. Caliper change in lactation was determined as the caliper units at weaning minus the caliper units pre-farrowing. Response variables included proportion of born alive and stillborn piglets, lactation feed intake, as well as removal and mortality risk for all causes, or specifically for reproductive and pelvic organ prolapse (POP) causes. Data were analyzed using generalized linear mixed models, hazard ratio analysis, and survival models with the lmer, glmer, and surv functions of R. Sow served as the experimental unit. Caliper measurements at farrowing had curvilinear associations (P< 0.05) with percentage born alive piglets and percentage stillborn piglets. Increasing caliper units at farrowing resulted in linear reduction (P< 0.05) in lactation average daily feed intake and in linear increase (P< 0.05) in caliper losses during lactation. Sows losing 1 to 2, 3 to 4, or 5 and greater caliper units in lactation had 1.5, 1.8, and 2.4 times, respectively, greater risk (P< 0.05) of being removed from the herd in the next cycle compared with sows that gained 0 or more units. Reduced caliper units in due-to-farrow sows resulted in reduced probability (P< 0.05) of survival in the next cycle considering prolapse removal reasons. Sows with due to farrow caliper units of 12 to 15 had 1 to 1.6 times (95% Odd Ratio Confidence Interval), 9 to 11 had 1.2 to 2.1 times, and less than 9 caliper units 3.1 to 3.2 times greater risk of death or being removed from the herd due to POP compared with those with >15 units. Reduced caliper units in due-to-farrow sows resulted in reduced probability of survival in the next cycle considering all removal and mortality causes. Specifically, sows with less than 9 caliper units at farrowing had 2.0 times greater risk (P< 0.05) of removal and 4.4 times greater risk (P< 0.05) of mortality compared with sows with over 15 caliper units. In summary, both under and over-conditioned sows have reduced productivity. Underconditioned sows are at greater risk for mortality and for POP related removal.

This study was conducted to investigate the impacts of the removal of zinc oxide (ZnO) supplemented at pharmaceutical levels and different nutritional plans on the growth performance, health, and behavior of nursery pigs from different genetic sire lines. A total of 1,440 newly weaned barrows and gilts were housed into nursery pens with 30 pigs/pen (0.25m2/pig). Pigs were assigned to eight groups following a randomized complete block design arranged on a 2 x 2 x 2 factorial arrangement [Genetic sire line: PIC 337 or PIC 800; ZnO supplementation: 0 or 2,500 ppm; nutritional plan: Control (PIC recommendation) or Treatment (TRT)]. Pigs were fed in three dietary phases (P1:7 d; P2: 21 d; P3: 21 d). The nutrient levels of the TRT for each phase consisted of reduced crude protein (P1: 21 vs. 18.43%; P2: 20.80 vs. 18.73%), SID Lys (P1: 1.40 vs. 1.20%; P2: 0.35 vs. 1.20%), net energy (P1: 2,450 vs. 2,352 kcal/kg; P2: 2,450 vs. 2,377 kcal/kg) and lactose levels (P1: 15 vs. 7%; P2: 7 vs. 5%), and use of calcium formate instead of calcium carbonate for both P1 and P2, and pigs receiving the same diet in P3. Health and behavior were assessed through ear lesion (weekly during P3) and fecal (weekly during P1 and P2) scoring, mortality/removals, and medication control. Growth performance was assessed by individually weighing pigs and recording feed disappearance every week throughout the experimental period. Data were analyzed using a generalized linear model considering pen as the experimental unit. Models included treatments and their interactions as fixed effects, and block and pen within block as the random terms. Pigs fed ZnO showed greater (P< 0.05) overall average daily gain (ADG; 495 vs. 456 g/d) and average daily feed intake (ADFI; 681 vs. 633 g/d); and decreased (P< 0.05) diarrhea incidence (DI; 3.64 vs 10.21%) at d 14 after weaning and mortality/removals (2.31 vs. 5.11%) compared with pigs fed no ZnO. No significant differences were detected between the nutritional plans for performance traits (P> 0.05); however, pigs fed the TRT had less (P< 0.05) DI (7.54 vs. 11.43%) at d 7 after weaning than pigs fed the control nutrition plan. Regarding the genetic sire lines, PIC 337 pigs showed greater (P< 0.05) overall body weight (26.1 vs. 25.4 kg), ADG (486 vs. 465 g/d) and ADFI (666 vs. 648 g/d); and decreased (P< 0.05) mortality/removals (2.54 vs. 4.66%) and DI (6.92 vs. 12.41%) at d 7 after weaning compared with PIC 800 pigs. In summary, PIC 337 pigs fed ZnO under the control nutritional program showed greater growth performance during the nursery period. This study reaffirmed the benefits of ZnO fed to nursery pigs during the post-weaning period; however, since different countries are banning or reducing the use of ZnO, nutritional strategies should be considered to not negatively impact the health and subsequent performance of nursery pigs.

This study was conducted to evaluate the effects of dietary NE on growth performance, carcass characteristics, and removal and mortality rates of grow-finish pigs. A total of 1,927 pigs [initial body weight (BW) 23.3 ± 0.23 kg] were used in a 125-d study. Pens of pigs were blocked by BW and randomly allotted to dietary treatments in a randomized complete block design with 23 to 26 pigs/pen and 15 replications/treatment. Pens received 1 of 5 diets with decreasing NE based on Eq. 1-8 NRC (2012) using proximate analysis of the major ingredients. A corn-soybean meal-based control diet was blended with a low energy diet that contained 8% less NE through inclusion of 25% wheat middlings and 15% DDGS (6% oil) to achieve intermediate NE levels. Thus, dietary NE fed through 5 dietary phases were: phase 1 (2,432, 2,383, 2,335, 2,286, and 2,237 kcal/kg); phase 2 (2,463, 2,413, 2,363, 2,315, and 2,266 kcal/kg); phase 3 (2,495, 2,445, 2,395, 2,345, and 2,295); phase 4 (2,518, 2,468, 2,417, 2,367, and 2,317 kcal/kg); and phase 5 (2,537, 2,486, 2,435, 2,384, 2,334 kcal/kg). Dietary phases were fed from approximately 23-40, 40-60, 60-80, 80-105, and 105-133 kg BW, respectively. Overall, reducing NE decreased (linear, P< 0.001) average daily gain (ADG) and final BW and increased (linear, P< 0.001) average daily feed intake (ADFI), resulting in decreased (linear, P< 0.001) gain to feed ratio (G:F; Table). Decreasing NE also tended to increase (linear, P= 0.073) the percentage of removals, with no evidence of difference (P> 0.10) in mortality. Reducing NE worsened (linear, P< 0.001) caloric efficiency (CE) based on NRC nutrient loading values, but improved (linear, P≤ 0.003) CE based on INRA (2008) or Brazilian Tables for Poultry and Swine (2017) nutrient loading values. When formulating diets using CVB (2021) nutrient loading values, decreasing NE did not influence CE (P> 0.10). For carcass characteristics, decreasing NE decreased (linear, P< 0.001) HCW, backfat depth, and carcass yield. However, decreasing NE increased (linear, P≤ 0.024) loin depth and percentage lean. When considering CE on a carcass gain basis, decreasing NE worsened (linear, P≤ 0.004) CE based on NRC or CVB nutrient loading values, but improved (linear, P< 0.001) CE based on INRA nutrient loading values. Decreasing NE resulted in no differences (P> 0.010) in CE based on Brazilian Tables nutrient loading values. These results suggest that the NRC database overestimates NE contributions of fibrous ingredients, such as wheat middlings and corn DDGS, while the INRA database underestimates their contributions to NE, whether CE is calculated based on live or carcass gain. Meanwhile, NE values in the CVB database appear to assess nutrient values more accurately for NE based on live gain but underestimate their value on a carcass basis. The Brazilian tables appear to underestimate the contributions of fibrous ingredients to dietary NE on a live basis, but more accurately value their contributions on a carcass basis.

The objective of the trial was to investigate the protein deposition pattern of PIC337×Camborough commercial pigs. A total of 1,064 barrows and gilts [PIC337×Camborough, initial body weight (BW) = 6.0 ± 0.1 kg] were used in the trial with 38 mixed sex pens, 28 pigs per pen. At the beginning of the trial, the lightest 10% of the barrows and gilts were selected and placed in four pens (equal numbers of barrows and gilts within a pen), and the remaining pigs were randomly placed into the other pens (equal numbers of barrows and gilts within a pen). A common 6-phase corn-soybean based wean-to-finish diets were fed throughout the trial. Dietary net energy and standardized ileal digestible lysine levels were (6-10 kg BW: 2,600 Kcal/kg and 1.35%; 10-20 kg BW: 2,520 Kcal/kg and 1.30%; 20-38 kg BW: 2,470 Kcal/kg and 1.20%; 38-72 kg BW: 2,450 Kcal/kg and 0.98%; 72-127 kg BW: 2,450 Kcal/kg and 0.87%; and 127-149 kg BW: 2,450 Kcal/kg and 0.77%). On d 97 after placement, 5 barrows and 5 gilts with BW close to pen average were selected for individual BW by a portable scale and 10thrib backfat and loin depth measurements (ExaGo portable ultrasound scanner, Imv imaging, UK). Then on d 111, 117, 136, 142, and 167 after placement, the same 5 barrows and 5 gilts were measured for individual BW, 10thrib backfat and loin depth. The fat-free lean mass is estimated by the equation 6.783-0.6198×(10thrib backfat depth, mm)+0.1578×(10thrib loin depth, mm)+1.0362×(warm carcass weight, kg). A constant carcass yield of 75% was used to estimate warm carcass weight. Data were analyzed using a linear mixed model in R Studio (Version 3.5.2, R Core Team; Vienna, Austria). The average BW of pigs at the 6 measurements were: 77.2, 92.4, 99.2, 122.5, 128.0, and 153.6 kg, respectively. The average daily gain (ADG) was 1,139, 1,155, 1,145, 1,126, and 977 g/d for 77.2 to 92.4 kg BW, 92.4 to 99.2 kg BW, 99.2 to 122.5 kg BW, 122.5 to 128.0 kg BW, and 128.0 to 153.6 kg BW, respectively. The average daily 10thrib backfat depth gain was 0.05, 0.08, 0.15, 0.17, and 0.20 mm/d. The average daily 10thrib loin depth gain was 0.42, 0.43, 0.41, 0.39, and 0.23 mm/d. The average daily fat-free lean mass gain (ADFFLG) was 547, 551, 528, 515, and 422 g/d. The fitted quadratic model for ADG is 83.57782 + 19.90632 × (BW, kg)-0.09176×(BW, kg)2, and the calculated maximum ADG was 1,163 g/d when BW was 108.5 kg. The fitted quadratic model for ADFFLG is 85.90926 + 9.23773 × (BW, kg) - 0.04591 × (BW, kg)2, and the calculated maximum ADFFLG is 550.6 g/d when BW was 100.6 kg. Under the conditions of the current trial, PIC337×Camborough pigs reaches the maximum rate of protein deposition at BW between 100.6 and 108.5 kg.

The objective was to determine the effects of dietary standardized ileal digestible (SID) lysine (Lys) levels and SID tryptophan (Trp) to Lys ratios on growth performance and behavior of late-nursery to finish maternal barrows. A total of 2,293 barrows (PIC Camborough, initially 11.9 ± 0.35 kg) were used in this trial with 96 mixed-sex pens and 23 to 25 pigs/pen. There was a total of 6 dietary phases: P1:11.9-29.5 kg; P2:29.5-49.6 kg; P3:49.6-62.6 kg; P4:62.6-80.3 kg; P5:80.3-103.3 kg; and P6:103.3-137.8 kg. Pens were blocked by body weight and randomly allotted to 1 of 6 treatments:T1: 100% Lys (dietary SID Lys levels meet PIC SID Lys recommendation) and 21.0% of SID Trp:Lys ratio; T2: 100% Lys and 18.5% of SID Trp:Lys ratio; T3: 100% Lys and 16.0% of SID Trp:Lys ratio; T4: 80% Lys (dietary SID Lys levels meet 80% of PIC SID Lys recommendation) and 21.0% of SID Trp:Lys ratio; T5: 80% Lys and 18.5% of SID Trp:Lys ratio; and T6: 80% Lys and 16.0% of SID Trp:Lys ratio for P1-P2 and then 100% Lys and 18.5% of SID Trp:Lys ratio for P3-P6. Ear lesion (EL) was monitored during P2-P5. Data were analyzed using a linear mixed model in R Studio (Version 3.5.2, R Core Team; Vienna, Austria). Pigs fed T1 and T2 showed improved average daily gain than T6 (P< 0.05), with other treatments intermediate (Table 1). Pigs fed T2 showed improved average daily feed intake as compared with T6 (P< 0.05), with other treatments intermediate. There was no evidence for significant difference on feed-to-gain ratio or mortality. Removal was significantly greater for pigs fed T6 compared with all other treatments (P< 0.05). Pigs fed T2 had significantly greater hot carcass weight than T4, with other treatments intermediate. There was no evidence for significant differences on carcass yield or lean percentage. Pig fed T6 had significantly greater incidence of EL in P2 than all other treatments (P< 0.05). Pigs fed T4 and T6 had greater incidence of EL in P3 than T1 (P< 0.05), with other treatments intermediate. Pigs fed T5 and T6 had significantly greater incidence of EL in P4 than T1, T2, and T3 (P< 0.05), with T4 intermediate. During P5, pigs fed T4 and T5 had the greatest incidence of EL (P< 0.05), while pigs fed T6 had significant greater incidence of EL than T3 (P< 0.05), with T1 and T2 intermediate. In conclusion, dietary SID Lys and SID Trp:Lys ratio less than PIC recommendation during late-nursery-to-grower phase resulted in compromised overall growth performance of maternal barrows, even with restored dietary SID Lys and SID Trp:Lys levels in finish phase. Dietary SID Lys level and/or SID Trp:Lys ratios lower than PIC recommendation may result in greater incidence of aggression behavior in maternal barrows.

The present study aimed to evaluate the impact of using different dietary standardized ileal digestible (SID) lysine (Lys) plans on growth performance and carcass characteristics of grow-finish pigs coming from high or low breeding value boars. A total of 2,080 pigs (PIC 800 × PIC Camborough) were housed in 20 mixed sex pens (26 pigs/pen), blocked by body weight (BW), and randomly allotted in a 2 × 2 factorial arrangement with boar breeding value (high or low) and nutrition Lys plan (current SID Lys curve recommendation for PIC 800 as % of PIC 337 SID Lys curve or alternative SID Lys curve). Pigs were weaned at 21 d of age (6.1 ± 0.05 kg BW) and followed during the wean-to-finish period until reach the market slaughter weight. Pigs were fed either the current recommendation or an alternative SID Lys curve for PIC 800, in a 6 phase feeding program: phase 1 (6-11 kg; 100 vs 100%, respectively); phase 2 (11-23 kg; 97 vs 100%, respectively); phase 3 (23-45 kg; 97 vs 100%, respectively); phase 4 (45-73 kg; 97 vs 95%, respectively); phase 5 (73-102 kg; 97 vs 95%, respectively); and phase 6 (102-132 kg; 97 vs 90%, respectively). Pigs were fed isoenergetic diets. Performance and carcass traits, and removals and mortality were recorded. Data were analyzed using mixed models in R, and considering pen as the experimental unit for performance traits and individual carcasses for carcass traits. There was no evidence of interaction between boar breeding value and nutrition plan factors. Overall, high breeding value pigs had greater average daily gain (ADG; 0.84 ± 0.005 g/d) compared with low breeding value pigs (0.82 ± 0.005 kg/d; P< 0.01), which was driven by increased average daily feed intake (ADFI; 1.92 ± 0.011 and 1.89 ± 0.011 kg/d, respectively; P< 0.05; Table 1). Moreover, high breeding value pigs had greater hot carcass weight (HCW; 97.8 ± 1.09 kg), carcass yield (74.1 ± 0.23%), backfat thickness (16.3 ± 0.29 mm) and lower lean meat % (57.0 ± 0.21%) compared with low breeding value pigs (96.0 ± 1.09 kg; 73.7 ± 0.23 %; 15.4 ± 0.28; 57.5 ± 0.21%, respectively; P< 0.05; Table 1). Regarding nutrition plan, no significant differences were observed for overall performance traits between pigs fed the current or alternative SID Lys curve (P> 0.05; Table 1). Nevertheless, pigs fed the alternative SID Lys curve had heavier HCW (97.3 ± 1.09 kg) compared with pigs fed the current SID Lys curve (96.6±1.09 kg; P< 0.05; Table 1). No significant differences were observed for overall removals and mortality by breeding value or nutrition Lys plan (P> 0.05). In summary, grow finish pigs from high breeding value boars have an improved productive performance. PIC 800 pigs may achieve the same productive performance with lower lysine levels at the end of the grow-finish period.

The present study aimed to evaluate the impact of using different dietary standardized ileal digestible (SID) lysine (Lys) plans on growth performance of PIC 337 and PIC 800 sired grow-finish pigs. A total of 2,016 gilts and barrows were placed in 2 separate rooms with 48 single sex pens each (21 pigs/pen; 0.69 m2/pig). Pens were blocked by body weight (BW) and randomly allotted in a 2 × 2 × 2 factorial arrangement with genetic line (PIC 337 or 800), sex (barrows or gilts), and nutrition plan (current SID Lys curve recommendation for PIC 800 as % of PIC 337 SID Lys curve or alternative SID Lys curve) as factors. Pigs (27.4 ± 1.41 kg BW) were followed during the grower-finisher phase until slaughter. Pigs were fed either the current recommendation or an alternative SID Lys curve for PIC 800, in a 5 phase feeding program: phase 1 (23-40 kg; 97 vs 100%, respectively); phase 2 (40-60 kg; 97 vs 95%, respectively); phase 3 (60-80 kg; 97 vs 95%, respectively); phase 4 (80-105 kg; 97 vs 95%, respectively); and phase 5 (105-135 kg; 97 vs 90%, respectively). Pigs were fed isoenergetic diets. Performance and carcass traits, and removals and mortality were recorded. Data were analyzed using mixed models in R, and considering pen as the experimental unit for performance traits and individual carcasses for carcass traits. There was no evidence of interaction between genetic line and nutrition plan factors. Overall, PIC 337 vs 800 pigs did not differ on average daily gain (ADG; P> 0.05), but PIC 337 pigs consumed 150 g/d less and were 0.1 more feed efficient than PIC 800 pigs (P< 0.05; Table 1). Moreover, PIC 337 pigs had 1.9 kg less of hot carcass weight, but 2.1 mm more of loin depth compared with PIC 800 pigs (P< 0.05; Table 1). Regarding nutrition plan, no significant differences were observed for overall performance and carcass traits between pigs fed the current or alternative SID Lys curve (P> 0.05; Table 1). Additionally, no significant differences were observed for overall removals and mortality by genetic line or nutrition plan (P> 0.05; Table 1). In summary, different genetic sire line (PIC 337 and PIC 800) differed on performance and carcass traits. Further research is needed to continue studying the genetic evolution and nutrition plan for each genetic sire line in the grower-finisher period to understand their nutrient requirements.

The objective of this study was to investigate the effects of feeding a stabilized fish oil source to different genetic lines on boar semen quality. A total of 127 boars representing three genetic lines (PIC 337, PIC 800, and PIC L03; Hendersonville, TN) at a commercial boar stud were balanced by age, body condition, and previous semen quality and randomly allotted to one of two dietary treatments within genetic line. Boars were assigned to either receive Control; a daily top dress of 32g of corn starch; or Fish oil; a daily top dress of 32g of Salmate DHA+ (The Ballard Group, 2407 Ashland Ave., Cincinnati, OH 45206 USA) to provide 2.38 g of docosahexaenoic acid (DHA). The top-dress supplementation was provided by placing it on top of the daily ration of feed for each individual boar on the floor once each day immediately after their feed has been delivered to them. Supplementation lasted for 16 wk from June-September, 2023 during which weekly semen collection was performed. Semen was evaluated at the stud for concentration and motility parameters using computer assisted semen analysis. Data was analyzed using generalized linear mixed models with the lmer and glmer functions of R. Boar was the experimental unit, with dietary treatment, genetic line, and their interaction tested as fixed effects while age at collection served as a covariate. Boar nested within treatment combinations was used as a random effect to account for repeated measurements within the same boar. There was no evidence (P> 0.10) for dietary treatment by genetic line interaction for any response criteria (Table 1). There was no evidence of fish oil supplementation effects (P> 0.10) on semen volume, concentration, total sperm cells per ejaculate, percentage of accepted ejaculates, or number of doses produced per accepted ejaculate. There was no evidence of fish oil supplementation effects (P> 0.10) on percentage motile sperm cells, or percentage of proximal and distal droplets and abnormal tails. Line 800 boars had the least (P< 0.05) semen volume, but greatest (P< 0.05) sperm concentration, resulting in no evidence for differences (P> 0.10) between the three genetic lines in total sperm cells per ejaculate. Line 03 boars had increased (P< 0.05) percentage of rejected ejaculates as well as decreased number of doses produced per accepted ejaculate (P< 0.05) compared with lines 337 and 800 boars. There was no evidence for differences (P> 0.10) in sperm motility, proximal and distal droplets, or abnormal tails between the three genetic lines. In summary, maternal line boars had an increased proportion of rejected ejaculates per boar and a decreased number of doses produced compared with terminal line boars. Feeding a stabilized fish oil to provide 2.38 g of DHA did not improve semen during summer months.

Our objective was to determine the effects of increasing daily dietary standardized ileal digestible (SID) lysine (Lys) intake during d 35 to 112 of gestation on sow and litter performance. A total of 704 gilts and sows (PIC Camborough) were used. Females were group-housed after d 35 of gestation and individually fed with electronic sow feeders (ESF). At d 35 of gestation, females were balanced for body weight (BW) and caliper scores within parity categories, and randomly allotted to 1 of 4 treatments. Treatments consisted of increasing daily dietary SID Lys intake (11.1, 13.5, 16.1, and 18.5 g/d). Both gilts and sows received 2.37 kg/d of a gestation diet containing 3.17 Mcal of ME/kg, which was estimated to avoid feeding females below their maintenance requirements throughout the entire gestation. Treatments were achieved by different blend of low (0.47% SID Lys) and high (0.78% SID Lys) Lys diets via ESF based on the set feed allowance for females. Sow was the experimental unit and data were analyzed using generalized linear mixed models with the lmer and glmerfunctions of R, considering treatment, parity, and their interaction as fixed effects. There was no evidence (P> 0.10) of treatment and parity interaction for any response criteria. Body weight at d 112 of gestation and BW change from d 35 to 112 of gestation increased (linear; P< 0.05) with increasing daily dietary SID Lys intake (Table 1). No evidence for SID Lys treatment differences were observed for BW at weaning or BW change during lactation (P> 0.10). There was no evidence (P> 0.10) for treatment differences on caliper score (CS) at d 35 of gestation, d 112 of gestation, at weaning, or CS changes during gestation and lactation. There was no evidence for treatment difference on total born, percentage stillbirth and percentage of mummified fetuses (P> 0.10). However, there was a marginal reduction in percentage born alive piglets (quadratic, P= 0.056), with the least proportion of piglets born alive observed in females receiving 16.1g of daily SID Lys intake from d35 to d112 of gestation. Increasing daily dietary SID Lys intake during d 35 to 112 of gestation did not affect piglet birth weight, piglet average daily gain during lactation, proportion of removed pigs, and proportion of dead pigs during lactation. In summary, increasing daily dietary SID Lys intake during d35-to-112 of gestation increased female BW; however, no evidence of benefits was observed for female reproductive performance and litter performance during lactation.

Our objective was to determine the effects of increasing standardized ileal digestible (SID) lysine (Lys) levels on growth performance and carcass characteristics of late-nursery-to-finish pigs sired by PIC 800 boars. Barrows and gilts [n = 1,00; PIC800×Camborough, initial body weight (BW) = 10.9 ± 0.39 kg] were used in a 142-d growth trial with 40 mixed sex pens, 10 pens per treatment, and 25 pigs per pen. At the beginning of the trial, pens were blocked by BW and randomly allotted to one of four treatments (overall dietary SID Lys level as 87, 95, 102, or 110% of PIC SID Lys recommendations) in a randomized complete block design. Diets were corn-soybean meal (SBM)-based, and treatments were achieved through the inclusion of SBM with adjustments of corn and choice white grease. Diets were fed in 7 phases (11-17, 17-34, 34-44, 44-57, 57-77, 77-95, and 95-133 kg) and formulated to be iso-caloric across treatments for each phase. Within each phase, only the diets of the least and greatest SID Lys levels were manufactured, and the diets of intermediate SID Lys levels were blended by the automatic feeding system in the research facility. Growth performance data were analyzed using the GLIMMIX procedure in SAS (Version 9.4, SAS Institute, Inc., Cary, NC) and considered pen as the experimental unit. The statistical model considered fixed effects of SID Lys levels and random effects of the block. Mortality and removals were also analyzed using the GLIMMIX procedure and specified a binomial distribution. All data are reported as least square means and considered statistically significant at P< 0.05 and marginally significant at P< 0.10. Increasing overall dietary SID Lys levels reduced overall average daily feed intake (linear, P= 0.045) and increased overall gain-to-feed ratio (linear, P= 0.002), but there was no evidence for a difference across treatments for overall average daily gain (P> 0.10) or overall removal and mortality rate (Table 1; P>0.10). Pigs fed overall SID Lys level as 102% of PIC recommendation had significantly greater carcass yield compared with those fed 95 or 110% (P< 0.05), with the pigs fed 87% being intermediate. Increasing overall dietary SID Lys levels reduced backfat depth (linear, P< 0.001) and increased lean yield (linear, P= 0.012), but there was no evidence for a difference among treatments for loin depth (P> 0.10). In conclusion, increasing overall dietary SID Lys level beyond PIC recommendations through increasing SBM levels resulted in improved feed efficiency, backfat depth, and lean yield of 11 to 133 kg pigs sired by PIC 800 boars.

A meta-analysis was conducted to determine the standardized ileal digestible (SID) lysine (Lys) recommendations for 11–150 kg PIC pigs housed under commercial conditions utilizing the INRA feed ingredients database. Data from 29 trials dating from 2013 to 2020 utilizing 48,338 pigs were recorded in a database. Number of pens/treatment and pigs/pen ranged from 9 to 16 and 12 to 25, respectively. Sire lines were PIC 337 in 25 trials, PIC 327 in 3 trials, and PIC TR4 and 327 in 1 trial. Dam lines were PIC Camborough in 18 trials and PIC Camborough 29 in 9 trials. The SID Lys levels reported in each trial were used, and the SID Lys to calorie ratio curves were built for both metabolizable energy (ME) and net energy (NE) systems using the feed ingredient composition in INRA for energy levels. The response variables, average daily gain (ADG) and feed efficiency (G:F), were analyzed within 7 phases using generalized linear and non-linear mixed models with heterogeneous variance (Gonçalves et al., 2016). Phases consisted of the following body weight ranges: 11-23, 23-41, 41-59, 59-77, 77-104, 104-127, and 127-150 kg . Each treatment mean within a trial (n = 288) was considered the experimental unit and each trial was used as a random effect. There was no evidence for an interaction between sire lines or dam lines and treatment (P> 0.10). The SID Lys to calorie recommendations are based on the average of the requirement estimates for ADG and G:F. At these levels, approximately 100% of maximum ADG and 99.7% of maximum G:F are achieved. After determining the requirement estimates within each of the 7 weight breaks, a quadratic equation of Lys to calorie ratio was fit for each energy system. The equations are described as: g of SID Lys:Mcal of ME = 0.0001381709 × (weight, kg)2- 0.0366272129 × (weight, kg) + 4.6073086522; and g of SID Lys:Mcal of NE = 0.0000400092 × (weight, kg)2- 0.0235648387 × (weight, kg) + 6.2762350341. These data provide the estimated SID Lys requirements for maximal growth performance for PIC pigs from 11- to 150-kg based on the ingredients database of INRA.