SID Lys Research Articles

Developing a More Sustainable Protein and Amino Acid Supply of Laying Hens in a Split Feeding System.

Two model experiments were conducted to investigate the different protein and amino acid supply of laying hens fed split feeding (SF) diets. In Experiment 1, one conventional (C) and one SF dietary treatment were established, and the diets were implemented for 12 weeks. The concentrations of crude protein, SID Lys, Met, Met + Cys Arg, Val, Thr, Leu, Ile, and Trp of the SF morning diet were the same as in the C diet. The crude protein content of the SF afternoon diet was lower (92%), while the SID values of Lys, Met, Met + Cys were identical compared to the C diet (100%). The SF treatment resulted in a reduced protein/N intake, better feed conversion ratio, higher eggshell thickness and apparent ileal digestibility of Asp, Leu, Lys, Gly, and Ser, and lower concentration of N forms (total, fecal, NH4+, uric acid, urinary) in the excreta compared to the C treatment. In Experiment 2, a control and a low protein (-2% crude protein but the same SID values of Lys, Met, Met + Cys, Thr, Val) SF treatment were compared for 6 weeks. The low protein SF treatment led to a decreased protein/N intake, higher laying rate, lower egg weight, higher ileal digestibility of Ala, Asp, Leu, and Ile, and similar N emission compared to the control SF treatment.

440 The effects of reducing dietary nutrient density after the second dose of GnRF immunization (Improvest) on growth performance and carcass characteristics of gilts and intact males

Abstract Objectives were to determine the effects of reducing dietary nutrient density after the second dose of GnRF immunization (Improvest; Zoetis Inc.) on growth performance and carcass characteristics. Pigs (n = 1,008) were fed in five diet phases during the 102-d grow-finish period. Diets were formulated to meet 100% of recommended SID Lys to net energy established by PIC (2021) for physically castrated (PC) barrows/non-immunized gilts (regular diet), while diets for GnRF-immunized pigs were formulated with 120% SID lysine than PC barrows/ non-immunized gilts (nutrient-dense diet). During diet phase-4 (2 d after the second GnRF analogue dose), SID lysine and vitamins/trace minerals for the nutrient-dense diet were either maintained at 100% or reduced to 95% or 90%. During diet phase-5 (18 d after second GnRF analogue dose), SID lysine and vitamins/trace minerals nutrient-dense diet were either maintained at 100% or reduced to 90% or 80%. The study consisted of six pen replications (21 pigs/pen) of the following eight treatments: CON-NEG: traditional mixed-sex pigs (PC barrows and non-immunized gilts) that received the regular diet; CON-POS: traditional mixed-sex pigs that received the nutrient-dense diet; I-MALE-100: immunized males (I-MALES) that received the nutrient-dense diet with 100% density; I-MALE-95/90: I-MALES that received the nutrient-dense diet with 95% density during diet phase-4 and 90% density during diet phase-5; I-MALE-90/80 I-MALES that received the nutrient-dense diet with 90% density during diet phase-4 and 80% density during diet phase-5; I-FEM-100: immunized females (I-FEM) that received the nutrient-dense diet with 100% density; I-FEM-95/90: I-FEM that received the nutrient-dense diet with 95% density during diet phase-4 and 90% density during diet phase-5; I-FEM-90/80: I-FEM that received the nutrient-dense diet with 90% density during diet phase-4 and 80% density during diet phase-5. Data were analyzed with PROC MIXED of SAS, with pen serving as the experimental unit. In addition, linear effects of diet dilution for I-MALE and I-FEM pigs were tested using contrast statements. There were not significant linear effects of diet dilution for gain:feed or hot carcass weight in either the I-MALE (P > 0.28) or I-FEM (P > 0.78) pigs. For the overall period, gain:feed was improved by 7.4% for I-MALE pigs compared with the CON-NEG pigs and was improved by 1.6% for the I-FEM pigs compared with the CON-NEG pigs. Hot carcass weight was 3.6 kg greater for the I-MALE pigs compared with the CON-NEG pigs and 1.6 kg greater for the I-FEM pigs compared with the CON-NEG pigs. The results would suggest that removing nutrients during the post-second dose period of GnRF immunization does not negatively affect growth performance or carcass characteristics, while both I-MALE and I-FEM pigs are more efficient and heavier when compared with traditional mixed sex pigs.

Impacts of Dietary Standardized Ileal Digestible Lysine to Net Energy Ratio on Lipid Metabolism in Finishing Pigs Fed High-Wheat Diets.

The present study aimed to investigate the impacts of dietary standardized ileal digestible lysine to net energy (SID Lys:NE) ratio on lipid metabolism in pigs fed high-wheat diets. Thirty-six crossbred growing barrows (65.20 ± 0.38 kg) were blocked into two treatment groups, fed high-wheat diets with either a high SID Lys:NE ratio (HR) or a low SID Lys:NE ratio (LR). Each treatment group consisted of three replicates, with six pigs per pen in each replicate. The diminishing dietary SID Lys:NE ratio exhibited no adverse impacts on the carcass trait (p > 0.05) but increased the marbling score of the longissimus dorsi muscle (p < 0.05). Meanwhile, LR diets tended to increase the serum triglyceride concentration (p < 0.1). LR diets upregulated fatty acid transport protein 4 and acetyl-coA carboxylase α expression levels and downregulated the expression level of adipose triglyceride lipase (p < 0.05). LR diets improved energy metabolism via decreasing the expression levels of AMP-activated protein kinase (AMPK) α1, sirtuin 1 (SIRT1), and peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) (p < 0.05). Additionally, LR diets stimulated hepatic bile acid synthesis via upregulating the expression levels of cytochrome P450 family 7 subfamily A member 1 and cytochrome P450 family 27 subfamily A member 1, and downregulating farnesol X receptor (FXR) and small heterodimer partner (SHP) expression levels (p < 0.05). A lowered SID Lys:NE ratio affected the colonic microbial composition, characterized by increased relative abundances of YRC22, Parabacteroides, Sphaerochaeta, and Bacteroides, alongside a decreased in the proportion of Roseburia, f_Lachnospiraceae_g_Clostridium, Enterococcus, Shuttleworthia, Exiguobacterium, Corynebacterium, Subdoligranulum, Sulfurospirillum, and Marinobacter (p < 0.05). The alterations in microbial composition were accompanied by a decrease in colonic butyrate concentration (p < 0.1). The metabolomic analysis revealed that LR diets affected primary bile acid synthesis and AMPK signaling pathway (p < 0.05). And the mantel analysis indicated that Parabacteroides, Sphaerochaeta, f_Lachnospiraceae_g_Clostridium, Shuttleworthia, and Marinobacter contributed to the alterations in body metabolism. A reduced dietary SID Lys:NE ratio improves energy metabolism, stimulates lipogenesis, and inhibits lipolysis in finishing pigs by regulating the AMPKα/SIRT1/PGC-1α pathway and the FXR/SHP pathway. Parabacteroides and Sphaerochaeta benefited bile acids synthesis, whereas f_Lachnospiraceae_g_Clostridium, Shuttleworthia, and Marinobacter may contribute to the activation of the AMPK signaling pathway. Overall, body metabolism and colonic microbiota collectively controlled the lipid metabolism in finishing pigs.

109 Evaluation of net energy, standardized ileal digestible lysine, and soybean meal content interaction in 13 to 25 kg pigs using a central composite design

Abstract Pigs [n = 4,683; 337 × 1050, PIC; initial body weight (BW) = 13.0 ± 0.01 kg] were used in a 21-d trial to investigate the interaction of net energy (NE), standardized ileal digestible lysine (SID Lys), and soybean meal (SBM) content used at five different levels on growth performance of nursey pigs. Pigs were housed in mixed sex pens with 35 pigs per pen and assigned in a randomized complete block design to 15 dietary treatments using a circumscribed central composite design (CCD). Factorial and axial points had 7 repetitions, and the central points had a total of 24. Eight diets were formulated to various levels of NE, SID Lys, and SBM and blended to create the 15 dietary treatments. The NE ranged from 2,334 to 2,762 kcal/kg, SID Lys from 1.08 to 1.52%, and SBM from 25.5 to 35.9%. Diets were corn-soybean meal based and soy hulls and soybean oil were added to reduce or increase NE content of the diet. Feed grade amino acids and SBM were used to adjust SBM and SID Lys content and to maintain SID Thr, Trp, Met, Val, and Ile ratios relative to SID Lys. For NE, a linear effect (P ≤ 0.052) was observed for average daily gain (ADG) and average daily feed intake (ADFI), and linear and quadratic effect was found (P ≤ 0.047) for gain to feed ratio (G:F) with a reduction in growth performance as NE increased due to reduction in SID Lys:calorie. When increasing SID Lys, ADG (P ≤ 0.044) and G:F (P ≤ 0.020) increased quadratically (Table). Increasing SBM content linearly improved ADG (P = 0.039) and G:F (P &amp;lt; 0.001), respectively. There was also a significant interaction between SID Lys and SBM for G:F (P = 0.082), where SID Lys positively impacted G:F as SBM increased in the diet. When including the significant terms, the resulting models can be used to predict the ADG (kg) response = [0.579392 + (-0.0063389 × NE) + (0.0260796 × Lys) + (0.0067428 × SBM%) + (-0.0065721 × Lys²) adjusted R2 = 0.36], and G:F (kg/kg) response = [0.7013215 + (0.0035198 × NE) + (0.0264389 × Lys) + (0.0060863 × SBM%) + (-0.0048012 × NE²) + (-0.0031838 × Lys²) + (-0.0034413 × Lys × SBM) adjusted R2 = 0.65]. In conclusion, using a CCD, increasing SID Lys resulted in a quadratic improvement in ADG and G:F, with this improvement being greater when SBM also increased. Overall, we observed few interactions between SID Lys, SBM, and NE.

252 Evaluation of phase feeding and complete diet blending at different standardized ileal digestible lysine levels on finishing pig growth performance, carcass characteristics and diet costs

Abstract A total of 2,160 mixed-gender pigs [PIC 337 × 1050; initial body weight (BW) = 24.9 ± 0.97 kg) were used in the 120-d study to compare feeding strategies (phase feeding vs complete diet blending) at different SID Lys levels (90 vs 100% of suggested requirement estimates) on finishing pig growth performance, carcass characteristics, and economics. Pens of 27 pigs were assigned to 1 of 4 treatments in a completely randomized block design with barn and initial BW as blocking factors resulting in 20 pens/treatment. The treatments included two feeding programs: a 5-phase feeding strategy at either 90% (Phase-90) or 100% of SID Lys requirement estimates (Phase-100) or blending of complete diets with pre-defined mixing proportions of a low and high SID Lys diet to meet 90 (Blend-90) or 100% (Blend-100) of the SID Lys curve requirement estimates for 23 to 127 kg pigs. Lysine levels were based on PIC 2021 requirement estimates. The 90% SID Lys diets were formulated to contain 4.38, 3.73, 3.06, 2.66 and 2.44 g SID Lys per Mcal NE for phases 1 to 5, respectively. The 100% SID Lys diets were formulated to contain 4.86, 4.15, 3.40, 2.96 and 2.71 g SID Lys per Mcal NE for phases 1 to 5, respectively. Pigs in phase-feeding strategies were fed on a feed budget with 21, 65, 67, 63 and 62 kg per pig for phases 1 to 5, respectively. Final BW and overall average daily gain (ADG; d 0 to 120) were not affected by the feeding strategy nor by diet SID Lys levels. In contrast, overall average daily feed intake (ADFI0 of pigs fed by diet blending was less than those fed by phase feeding (P = 0.002) resulting in increased gain to feed ratio (G:F; P &amp;lt; 0.001) for pigs fed by diet blending (table). The SID Lys levels did not influence overall ADFI or G:F. Hot carcass weight, carcass yield, percentage lean, fat depth and loin depth were not affected by the feeding program. Despite the decreased overall ADFI and increased G:F of pigs fed by diet blending, feeding strategy resulted in no significant differences in economic criteria except for reduced feed cost per kg gain at high price scenario (P = 0.049) for diet blending. With low diet cost, the 90% SID Lys level resulted in decreased feed cost per pig and feed cost per kg gain than 100% SID Lys (P &amp;lt; 0.001), but differences were not detected in income over feed cost (IOFC). In conclusion, diet blending at either 90 or 100% of the SID Lys requirement estimate reduced ADFI and increased G:F without impacting average daily gain (ADG) or carcass characteristics. At ingredient prices used in this study, feeding strategies at either 90 or 100% SID Lys did not significantly affect IOFC, but feeding 90% of SID Lys recommendation reduced feed cost.

19 Evaluation of precision feeding standardized ileal digestible lysine to meet the requirements of lactating sows

Abstract Two experiments evaluated the effects of precision feeding lactating sows. In both experiments, sows were blocked by parity and allotted to treatment on d 2 of lactation. The first experiment included a total of 95 mixed parity sows and litters. Treatments included a control, NRC (2012), or INRA (2009) treatment curve. Sows on the NRC or INRA treatment curves received a blend of a low (0.25% SID Lys) and high (1.10% SID Lys) Lys diet using the Gestal Quattro Opti Feeder (Jyga Technologies, St-Lambert-de-Lauzon, Quebec, Canada) to target specific SID Lys intake/d based on parity and litter size according to NRC and INRA models. Control sows received only the high Lys diet. Blend of the high and low Lys diets were adjusted every 2 d based on actual Lys intake to more closely meet target Lys intake (NRC and INRA curves). Control sows had greater (P &amp;lt; 0.05) average Lys intake (76.7 g/d) compared with sows fed either NRC (53.1 g/d) or INRA (42.8 g/d) curves (Table). Pigs from sows fed the high Lys diet had greater (P &amp;lt; 0.05) body weight at weaning and average daily gain (ADG) compared with pigs from sows fed INRA treatment, with NRC curve fed sows intermediate. Nitrogen excretion, estimated from NRC equations, was greatest (P &amp;lt; 0.05) in sows fed the high Lys diet, followed by sows fed the NRC curve, and INRA curve sows the least. In Exp. 2, 56 mixed parity sows and litters were used. Treatments included a control where sows were provided a high Lys (1.10% SID Lys) diet and two treatments where sows were fed either a static or dynamic blend of a low (0.40 % SID Lys) and high Lys diet to target a specific SID Lys intake/d based on parity and litter size. The dynamic curve blend was adjusted based on actual Lys intake every 2 d to reach target Lys intake while the static curve was not adjusted. Lysine intake curves were based on the NRC (2012), but targets were increased by 20% to reach an average Lys intake of 60 g/d across parities. Control sows had greater Lys intake (P &amp;lt; 0.05; 77.7 g/d) compared with sows fed the blend curves, with no differences between the two blend curves (P &amp;gt; 0.05; 60.1 vs. 59.7 g/d). There were no differences (P &amp;gt; 0.05) observed in litter size, piglet or litter weight at weaning, or ADG. Estimated nitrogen excretion was greater (P &amp;lt; 0.05) for sows on the control diet compared with both blend curves. These data would suggest that 60 g/d of SID Lys is sufficient to maximize litter weight gain for litter sizes of 13.5 weaned piglets. Overall, feed blending can be used to decrease N excretion while achieving similar performance compared with feeding a standard high Lys diet.

142 Evaluation of low SID lysine diets fed to enteric health challenged pigs on wean-to-finish performance

Abstract Producers have been adopting low crude protein or low SID Lys nursery diets to address enteric health concerns. Therefore, we evaluated the longitudinal impact of these strategies on lifetime pig performance. Weaned mixed sex pigs n = 588; initial body weight (BW) = 6.81 ± 1.34 kg] sourced from a poor enteric health flow, were randomly assigned to pens and to one of four nursery dietary treatments, fed for 7 wk. Following the nursery period, pens were then assigned to one of two grow-finish treatments, fed until marketing, to complete a 2 × 2 × 2 factorial design (n = 6 pens/treatment, 12 to 13 pigs/pen). Phase 1 nursery diets were formulated to a 1.10% or 1.40% SID Lys (nLLys or nHLys) with amino acids (AA) provided by both soybean meal (SBM) and crystalline AA or SBM only (nLSBM or nHSBM, respectively). Nursery phase 2 and 3 diets were formulated with a 0.05% decrease in SID Lys while maintaining a 0.30% differential between high and low lysine treatments. Following the nursery, grow-finish pigs were fed diets formulated to equal SID Lys:ME with either a conventional crystalline AA (gfLSBM) or high SBM diet lacking crystalline AA (gfHSBM) to meet AA requirements. During the nursery, enteric health was assessed by fecal pathogen PCRs and bacterial culture, confirming a high natural rotavirus and F18 enterotoxigenic Escherichia coli burden. Pig BW and pen feed disappearance were recorded at the beginning and end of each phase to calculate average daily gain (ADG), average daily feed intake (ADFI), and feed efficiency (gain to feed ratio; G:F). Data were analyzed with pen as the experimental unit and the fixed effects of nursery SID Lys (nLys), nursery SBM (nSBM), grow-finish SBM (gfSBM), and the two- and three-way interactions using ANOVA. There were no three-way interactions for ADG or ADFI on final performance and no two-way interactions of nLys by nSBM in the nursery. Additionally, there was no effect of nSBM on overall nursery ADG, ADFI, and G:F (P &amp;gt; 0.05). Pigs fed nHLys-gfHSBM (0.84 kg/d) had improved overall ADG versus pigs fed nLLys-gfHSBM (0.80 kg/d; interaction; P = 0.010). Final nursery ADG (0.47 vs. 0.42 kg/d), G:F (0.70 vs. 0.63), and ending BW (30.9 vs. 28.0 kg) were greater in pens fed nHLys compared with nLLys (P &amp;lt; 0.001). Grow-finish pigs fed gfHSBM were more efficient compared with gfLSBM overall (0.457 vs. 0.449, respectively; P = 0.016). Although pigs fed nHLys had improved ending ADG compared with nLLys (0.83 vs. 0.81 kg/d; P = 0.018, respectively), there were no differences in final BW (128.0 vs. 127.0 kg) or ADFI (1.83 vs. 1.80 kg/d; P &amp;gt; 0.05). In conclusion, low SID Lys enteric diets did not improve wean-to-market pig performance in enterically challenged pigs and there was no difference between amino acid sources (crystalline vs SBM).

282 Effect of dietary supplementation with guanidinoacetic acid, a creatine precursor, in gestating and lactating sows on sow and litter performance

Abstract Guanidinoacetic acid (GAA) is the immediate metabolic precursor of creatine. Sows undergo periods of high energy demand and dietary supplementation of GAA can support the creatine/phosphocreatine energy system. The objective of this study was to evaluate the effect of dietary supplementation of GAA in sows on sow and litter performance. Sows (n = 150; Danbred x Pietrain, parity 1 to 7) were allocated to two dietary treatments (75 sows/treatment), 0.0 or 0.1% GAA in both gestation and lactation phases and balanced by parity and body weight (BW). Gestation diets (2.87 Mcal ME/kg, 2.13 g SID Lys: Mcal ME, 0.21% SID Met, and 0.13% choline) were fed from d 1 to 107 of pregnancy and 4 d post-weaning; and lactation diets (3.14 Mcal ME, 3.18 g SID Lys: Mcal ME, 0.34% SID Met, and 0.14% choline) were fed from d 108 of gestation through the lactation (26 days). Sows were kept in the same treatment during gestation and lactation. After farrowing, litters were standardized to 13 pigs per sow. Dietary supplementation with GAA during the gestation reduced sow feed intake (319.4 vs. 313.6 kg, P = 0.009), and did not affect sow BW at d 108 of gestation (284.2 vs. 282.8 kg, P = 0.889), born alive (15.70 vs. 15.92, P = 0.668), stillborn piglets (1.78 vs. 1.51, P = 0.332), and piglet BW at birth (1.34 vs. 1.32 kg, P = 0.591), for 0.0 and 0.1% GAA respectively. Dietary supplementation with GAA during lactation did not affect sow feed intake (181.1 vs. 181.5 kg, P = 0.999), sow BW at weaning (252.7 vs. 255.3 kg, P = 0.747) and wean-to-estrus interval (5.0 vs. 4.9 d, P = 0.978), and tended to reduce sow backfat loss at weaning (17.0 vs. 17.4 mm, P = 0.090), for 0.0 and 0.1% GAA, respectively. Sows fed GAA in lactation tended to have a greater number of pigs weaned (11.76 vs. 12.10, P = 0.088), and their piglets tended to have a greater average daily gain (ADG; 216.1 vs. 226.0 g/d, P = 0.062), have significantly heavier litters at weaning (81.87 vs. 86.28 kg, P = 0.048) and their litters have a greater BW gain (64.07 vs. 68.60 kg, P = 0.028). In conclusion, dietary supplementation with 0.1% of GAA to gestating and lactating sows improved litter weight at weaning, litter weight gain, and number of pigs weaned and did not affect sow BW and reproductive performance. More studies are needed to evaluate if supplementing GAA in gestation has a carryover effect on the lactation period.

18 Effect of precision feeding standardized ileal digestible lysine to lactating sows compared with conventional feeding strategies in a commercial farm

Abstract A total of 728 sows and litters were used in a 19-d lactation study to evaluate effects of precision feeding SID Lys and other amino acids on sow and litter performance and feed cost in a commercial farm. Sows were blocked by parity and allotted to 1 of 2 treatments at entry into farrowing. Treatments consisted of a control diet or a feed blending curve. Two diets were used to create treatment curves, a low Lys diet (0.60% SID Lys) or a high Lys diet (1.07% SID Lys). Sows on the control treatment were fed only the high Lys diet and sows on the blend curve were fed a blend of the low and high Lys diets using the Gestal Quattro Opti Feeder (Jyga Technologies, St-Lambert-de-Lauzon, Quebec, Canada) to target a specific Lys intake/d. Lysine intake targets were based on the NRC (2012) model requirements, except targets were increased by 20% to reach average Lys intake of approximately 63 g/d. The blend of the low and high Lys diet was adjusted on d 7 and 14 for sows fed the blend curve in an attempt to reach target Lys intake. Average Lys intake was 87% of target Lys intake because feed intake was lower than predicted. Sows fed the control diet had greater (P &amp;lt; 0.001; 72.0 vs 54.8 g/d) Lys intake compared with sows on blend curves because they were fed only the high Lys diet (Table). No differences (P &amp;gt; 0.05) in body weight (BW), backfat, loin depth, caliper score, or average daily feed intake (ADFI) were observed. There were no differences (P &amp;gt; 0.05) in litter size at d 2 after equalization or weaning; however, piglets and litters from sows fed the control treatment tended to have greater weaning weights (P = 0.090) and average daily gain (ADG; P = 0.071) compared with piglets and litters from sows fed the blend curve, likely due to insufficient Lys intake for sows on the blend curve to maximize litter growth performance. Feed cost per sow was less (P &amp;lt; 0.05) for sows fed the blend curve in both a low and high ingredient price scenario. No differences (P &amp;gt; 0.05) in feed cost per kg of litter weight gain were observed; however, feed cost per weaned pig was less (P &amp;lt; 0.05) for sows on the blend treatment. Serum urea nitrogen was greater (P &amp;lt; 0.05) at weaning compared with d 10 for control fed sows and was greater (P &amp;lt; 0.05) than blend-fed sows at both time points. Sows fed the control diet had greater milk crude protein (P = 0.05) compared with sows fed the blend curve. While precision feeding sows using diet blending during lactation can be used to reduce feed cost, future research should focus on using technology to automatically adjust diet blend for low or high-feed intake sows to avoid the over or under-feeding of nutrients.

PSIV-20 Evaluation of pectinase on nursery pig performance

Abstract Non-starch polysaccharidases have been widely employed in swine production to enhance fiber digestion and nutrient utilization, yielding mixed results. Our objective was to evaluate the effects of an exogenous pectinase on performance of early nursery pigs. The study utilized 320 mixed sex freshly weaned pigs, 19-21 d of age [5.4 ± 1.1 kg body weight (BW), Camborough (1050) x 337, (PIC, Hendersonville, TN)], sourced from a commercial sow farm. Upon arrival, pigs were randomly allotted to four dietary treatments (10 pens/treatment, 6 gilts and 2 barrows/pen). All diets were fed in two phases consisting of 7 and 14 d over a 21-d study period. Phase 1 basal diets consisted of 40% soybean meal, 1.45% SID Lys, and 3,396 kcal/kg ME. Phase 2 basal diets consisted of 40% soybean meal, 1.375% SID Lys, and 3,396 kcal/kg ME. In both phases, exogenous pectinase was included at 0, 8, 40, and 80 (g/MT). Pen bodyweights and feed disappearance were collected at the start and end of each phase to calculate average daily gain (ADG), average daily feed intake (ADFI), and gain to feed ratio (G:F). Fecal consistency was scored for diarrhea presence daily. In all analyses, pens served as the experimental units. Growth performance and mortality/removals data were analyzed within phase and overall with the fixed effect of pectinase level, including the linear and quadratic effects of varying pectinase levels across the diets. No discernible health impacts were identified based on observations of mortality/removals and fecal consistency scores (P &amp;gt; 0.10). There were no notable main, linear, or quadratic effects observed on pig bodyweights during the trial. Overall, the diet had a significant impact on ADG (P &amp;lt; 0.05), showing a positive trend associated with pectinase inclusion (linear P = 0.08). This trend was supported by a 14% increase in the ADG of pigs that consumed the diet with 80 g/MT of pectinase, in contrast to pigs fed the control diet. Phase 1 did not exhibit any notable effects on performance in terms of main, linear, or quadratic trends. In contrast, during phase 2, the diet significantly affected the ADG of pigs, with all pectinase-containing diets promoting greater body weight gain compared with control-fed pigs (P &amp;lt; 0.05). Additionally, there was a tendency for a diet effect on GF in phase 2 (P = 0.09). Pigs that were fed the diet with 80 g/MT of pectinase observed a 14-22% improvement in feed efficiency compared with all the other dietary groups. In conclusion, the addition of pectinase to early nursery pig diets had the capacity to enhance pig performance without any adverse effects on pig health when feeding high soybean meal.

PSVI-21 The effects of soybean meal concentration and Yucca schidigera extract supplementation on growth performance of nursery swine

Abstract Soybean meal (SBM) is the primary plant-protein source for swine in the USA. However, SBM might not be suitable to be fed at high levels, particularly in the early post-weaning period. To offset these effects, pigs are gradually transitioning to diets with greater concentrations of SBM. Whereas, greater SBM concentrations can be detrimental, peer-reviewed studies have indicated that pigs fed diets with 30% SBM and supplemented with 125 ppm Yucca schidigera extract (YSE) from d 0-14 post-wean performed similarly to pigs fed diets with 15 and 20% SBM, from d 0-7 and d 7-14 post wean, respectively. Suggesting that pigs can be fed greater SBM concentrations without compromising performance. To confirm these findings, a total of 972 pigs [initial body weight (BW) = 5.4 kg) were used in a 38-d experiment. Pens of 27 pigs were randomly allotted to 1 of 4 dietary treatments with 9 replications per treatment. Dietary treatments were arranged in a 2 × 2 factorial with main effects of SBM concentration (15 or 31%) and YSE (0 or 125 ppm; DeOdorase Alltech, Inc., Nicholasville, KY). Pigs were fed a nursery program comprised of two phases. Phase 1 from d 0 to 21 (experimental feeding period) and Phase 2 from d 22 to -38 (common period). Phase 1 diets were formulated to contain 1.38% SID Lys and 2,600 kcal/kg NE. Phase 2 diets were formulated to contain 1.30% SID Lys and 2,565 kcal/kg NE. Data were analyzed using the GLIMMIX procedure of SAS (Cary, NC) in a randomized complete block design with pen serving as the experimental unit and initial BW serving as blocking factor. No significant SBM × YSE interactions (P &amp;gt; 0.10) were observed in growth performance in this study (Table 1). From d 0 to 21, pigs fed diets supplemented with YSE increased (P = 0.006) average daily feed intake (ADFI), which numerically improved (P = 0.16) average daily gain (ADG) and thus (P = 0.12) BW, despite SBM concentration. From d 21 to 38, pigs previously fed diets supplemented with YSE, maintained a marginally higher (P = 0.08) ADFI, which numerically increased (P = 0.12) ADG, resulting in marginally higher (P = 0.08) BW, despite SBM concentration. From d 0 to 38, pigs fed diets supplemented with YSE increased (P = 0.03) ADFI, which numerically improved (P = 0.10) ADG, resulting in marginally greater (P = 0.08) BW, despite SBM concentration. In conclusion, whereas pigs fed with greater SBM concentrations did not compromise performance, diet supplementation with YSE increased ADFI during the experimental and common periods, resulting in improved growth performance.

175 Impact of common dietary strategies on piglet growth and scouring with an enterotoxigenic Escherichia coli F18 challenge

Abstract This experiment evaluated the impact of various dietary treatments on the growth and scouring of piglets post-wean and following an enterotoxigenic Escherichia coli F18 infection (ETEC). A total of 240 pigs (PIC 337 x 1050, Genus, Henderson, TN) were randomly assigned to 40 mixed-sex pens (6 pigs/pen) for a 6-wk experiment. At arrival, all pigs were genotyped for fucosyltransferase (FUT1). Pens were assigned to five dietary treatments: NC (standard nursery diet without Zinc or carbadox, 22.31% CP, 1.46 SID Lys in Period 1); PC (NC + 3,750 ppm zinc oxide and carbadox); LCP (NC with low crude protein, 19.5% CP, 1.3% SID Lys in Period 1); FIB (NC with 8% wheat middlings); and Zinc (NC + 3,750 zinc oxide). Pig body weight (BW), feed disappearance, and feed conversion were evaluated for four periods: d 0-7, 7-14, 14-21, and 21-42. Scour scores were recorded daily for the first 28 d of the experiment to calculate weekly percentage of days scouring (scouring percentage). Pigs received a common diet from d 21-42. All pigs were orally inoculated with a field strain of ETEC on d 14 of the experiment. Blood was collected (8 mL) from one ETEC susceptible pig per pen on d 14 and 17, with a separate susceptible pig collected on d 20. These two pigs were euthanized on d 17 and 20, respectively, for tissue collection. Fecal swabs from susceptible pigs were collected on d 14, 16, 18, and 20 to measure ETEC shedding. Blood samples were analyzed for inflammatory markers, and villi: crypt within the ileum were measured. Data were analyzed using mixed model methods (SAS 9.4, Cary, NC) with pen as the experimental unit. Fixed effects of dietary strategy, experimental period, and the interaction were included for growth performance and scouring percentage. While overall growth performance was not significantly impacted by treatment, scouring percentage was impacted by treatment, period, and treatment x period interaction (P &amp;lt; 0.01). In the first week post-weaning (d 0-7), NC had the greatest scouring percentage (50%), while PC and LCP had the least (21.4%, P = &amp;lt; 0.01). For d 7-14, NC had the greatest scouring percentage (33.9%), while PC (P &amp;lt; 0.01%) and Zinc (14.3%) had the leastt. Post ETEC inoculation (d 14-21), fiber had the greatest scouring percentage (P &amp;lt; 0.01, 28.6%), with PC (5.4%) and Zinc (8.9%) having the least, and LCP (16.1%) and NC (21.4%) being intermediate. Interestingly, 1 wk post-ETEC inoculation, LCP had the greatest scouring percentage (30.4%), with PC (5.4%), NC (7.1%), and fiber (3.6%) having the least. Although LCP treatments initially reduced scours after weaning, they exhibited a delayed scouring response to ETEC infection compared with FIB, with an elevated scouring percentage persisting up to d 21-28.

12 Effects of increasing SID lysine (Lys) and metabolizable energy (ME) levels of lactation diets fed to young and multiparous sows

Abstract Providing insufficient lysine to lactating sows can reduce piglet performance and subsequent farrowing performance of sows. Current SID lysine and ME recommendations for lactating sows are approximately 60 g/d and 20 Mcal/d, respectively. Because of variations in feed intake during lactation, a portion of sows do not meet recommended Lys intake levels. There is no clear understanding of the Lys:Calorie ratio when dietary energy is increased in the summer to ensure adequate caloric intake. The objective was to evaluate a potential advantage of feeding diets with SID Lys and energy levels that exceed recommendations to lactating sows. A total of 855 sows were fed during the summer of 2023 in 2×2 factorial arrangement of treatments in a randomized complete block design. Factors included SID lysine [low (0.85%) vs high (1.11%)] and ME [low (3,183 kcal/kg) vs high (3,334 kcal/kg)]. Diets were formulated to deliver 61 g of SID lysine at 0.85% inclusion to sows that consume 7.2 kg of complete feed per day. Primary outcome variables were sow body composition, lactation average daily feed intake (ADFI), average piglet weaning weight, and pre-wean mortality. There were no interactions between treatments (P &amp;gt; 0.05). SID Lys intake was 61.2 and 76.4 g/d for low and high Lys, respectively (P &amp;lt; 0.01). ME intake was 21.9 and 23.4 Mcal/d for low and high energy, respectively (P &amp;lt; 0.01). Contrary to expectations, ADFI did not differ (P = 0.25) between sows fed the low- and high-energy diets, however, sows fed low lysine consumed 0.29 kg more feed (P &amp;lt; 0.01) per day compared with sows fed high lysine. There were no differences (P ≥ 0.70) in the number of piglets born alive for any treatment group. Sows fed high energy had 0.27 fewer (P &amp;lt; 0.01) still-born piglets per litter compared with sows fed low energy. Pre-wean mortality was also reduced (P = 0.05) by 0.76 percentage units in litters of sows fed the high-energy diet compared with litters of sows fed the low energy. Lysine level had no effects on farrowing and litter performance (P &amp;gt; 0.05). Litters from sows fed the high-energy diet gained 1.2 kg more (P = 0.05) body weight during lactation and tended to result in litter-weaned weights that were 1.5 kg heavier (P = 0.06) than litters from sows fed the low-energy diet. Feeding a diet with a greater lysine concentration during lactation reduced feed intake but did not affect litter performance. In contrast, increasing dietary energy immediately before farrowing and during lactation did not affect sow feed intake but reduced pre-wean mortality and resulted in fewer still-born piglets, greater litter gains, and heavier litter weaning weights.

200 Effects of zinc oxide removal and different nutritional plans on the growth performance, health, and behavior of nursery pigs from different genetic lines

Abstract 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 &amp;lt; 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 &amp;lt; 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 &amp;gt; 0.05); however, pigs fed the TRT had less (P &amp;lt; 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 &amp;lt; 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 &amp;lt; 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.

246 The effect of trypsin inhibitor unit concentrations from raw soybeans in grower pig performance and protein digestibility

Abstract Soybeans contain two major protease inhibitors, Kunitz trypsin and Bowman-Birk protease inhibitors, both of which are anti-nutritional components that can be directly linked to a reduction in amino acid bioavailability and growth performance in swine. Therefore, the objective of this study was to determine the level at which trypsin inhibitor units (TIU, expressed as TIU/mg of complete feed), coming from raw soybeans, in pig diets result in reduction in growth performance and digestibility. This study used 45 grower gilts initial body weight (BW) = 39.7 ± 2.1 kg] that were individually penned and fed one of five dietary TIU treatments (n = 9 pigs/trt) in a complete randomized design. Diets were representative of a commercial corn-soybean meal diet and formulated to have ranging TIU/mg of complete feed of 0.89, 1.77, 3.55, 6.99, and 11.54 TIU/mg utilizing raw ground soybeans and soybean meal at incremental levels. Analyzed diets contained 0.99, 2.23, 3.07, 6.49, and 9.38 active TIU/mg. Diets were balanced to the same grams of SID Lys:ME of 2.85 and NDF concentration of 7.4% utilizing soybean oil and soybean hulls, respectively. Individual feed intake was recorded throughout, and pig BW were collected on d 0, 21, and 27 to calculate average daily gain (ADG), average daily feed intake (ADFI), and feed efficiency gain to feed ratio (G:F). All pigs were placed into metabolism crates on d 21 for 6 d to determine apparent total tract digestibility (ATTD) of nitrogen (N), N excretion and N balance. Growth performance and ATTD data were analyzed with pig as the experimental unit and diet TIU level as a fixed effect using ANOVA, linear, and quadratic contrast models. Overall, ADG decreased as diet TIU increased (1.07, 1.03, 1.02, 0.91, and 0.83 kg/d, respectively, linear P &amp;lt; 0.001). However, no differences in ADFI (P &amp;gt; 0.10) were reported and this resulted in a decrease in G:F (0.48, 0.45, 0.43, 0.41, 0.36, respectively, linear P &amp;lt; 0.001) as dietary TIU concentrations increased from 0.99 to 9.38 TIU/mg. Compared with 0.99 TIU/mg, pigs fed 9.38 TIU/mg had a 9.32% reduction in final BW (68.7 vs. 62.3 kg, linear P &amp;lt; 0.001). Apparent total tract digestibility of N decreased when pigs were fed 9.38 TIU/mg compared with 0.99 and 2.23 TIU/mg (83.26% vs. 90.29% and 89.57%, respectively, P &amp;lt; 0.001). In conclusion, as total trypsin inhibitor units increase in complete feed of grower pigs, digestibility of protein, growth rates and feed efficiency are reduced in a linear manner.

PSIII-18 Effects of HiPhorius and Ronozyme HiPhos on performance of nursery pigs

Abstract The objective of this study was to evaluate the efficacy of the new phytase HiPhorius (encoded by a 6-phytase gene from Citrobacter braakii and expressed from Aspergillus oryzae; dsm-firmenich) compared with Ronozyme HiPhos (a 6-phytase product produced with a genetically modified strain of the filamentous fungus Aspergillus oryzae; dsm-firmenich) on performance of nursery pigs. A total of 528 weaned pigs [PIC Camborough female × PIC 337 boar; 19 d of age, initial body weight (BW) = 6.5 kg] were blocked by initial BW and gender and allotted to 48 pens which were randomly assigned to 1 of 4 dietary treatments (10 to 12 pigs/pen; 12 pens/treatment), including T1) Ronozyme HiPhos 3,000 FYT/kg, T2) HiPhorius 1,000 FYT/kg, T3) HiPhorius 1,500 FYT/kg, and T4) HiPhorius 2,000 FYT/kg. Pigs were fed a 3-phase feed-budget program, consisting of 1.4 kg/pig in Phase 1, 5.5 kg/pig in Phase 2, and Phase 3 diets fed to d 42 postweaning. Diets were formulated to be isocaloric and contained 1.41, 1.34, and 1.27% SID Lys for phase 1, 2, and 3, respectively. Phytase levels were tested at the same dose in phase 1 and 2 diets, while in phase 3, phytase levels were tested at 2,000 and 1,000 FYT/kg, respectively, for the Ronozyme HiPhos and HiPhorius treatments. During d 0-15 and d 0-22, pigs fed HiPhorius 1000 had reduced (P &amp;lt; 0.05) feed conversion than Ronozyme HiPhos and HiPhorius 2000. No significant treatment effects were observed on average daily gain (ADG) or average daily feed intake (ADFI) during these periods. During d 22-42, pigs fed HiPhorius 2,000 had greater ADG (P = 0.08), final BW (P = 0.09), and ADFI (P = 0.03) than HiPhorius 1,000 and Ronozyme HiPhos; however, there were no treatment effects on feed conversion. Overall (d 0 - 42), feeding HiPhorius 2,000 improved ADG compared with feeding Ronozyme HiPhos, HiPhorius 1,000, and HiPhorius 1,500 (476 vs. 458, 449, and 458 g, respectively; P = 0.07); however, similar ADFI and feed conversion were observed among treatments. Data from this study suggest that feeding HiPhorius at 2,000 FYT/kg provided greater ADG compared with feeding HiPhorius at reduced amounts or Ronozyme HiPhos. While the two sources of phytase had similar responses on nursery ADFI and feed conversion overall, feeding HiPhorius at 1,000 FYT/kg resulted in decreased feed conversion during the first 3 wk post-weaning.

247 Evaluating the use of soybean hulls on growth performance, carcass composition, and digestibility when fed to grow-finish pigs

Abstract The addition of fiber to grow-finish diets is commonly utilized in swine production formulation as energy costs increase. The objective of this study was to determine the effects of feeding soybean hulls (SBH) at increasing levels to grow-finish pigs on growth performance, carcass characteristics, and apparent total tract digestibility (ATTD) of nutrients. Utilizing 192 grower pigs [PIC 337×1050, initial body weight (BW) = 21.99 ± 2.75 kg] that were randomly assigned to split sexed pens (n = 12 pens/treatment), pens were assigned to one of four dietary treatments and fed over three feeding phases for the estimated BW ranges of 22 to 50 kg, 50 to 86 kg, and 86 to 127 kg. Diets were formulated to represent conventional corn and soybean meal diets, containing increasing levels of SBH at: 1) 0% SBH (0%); 2) 7.5% SBH (7.5%); 3) 15% SBH (15%); and 4) 22.5% SBH (22.5%). Within phase, diets had equal SID Lys:ME and energy was allowed to float. Individual BW and pen feed disappearance were collected for each phase to calculate pen average daily gain (ADG), average daily feed intake (ADFI), and feed efficiency gain to feed ratio (G:F). On d 56 of study and during phase 2, 32 gilts (n = 8) were placed into individual metabolism crates, where total urine and feces were collected for 72 h to measure ATTD of gross energy (GE), nitrogen (N), neutral detergent fiber (NDF), and acid detergent fiber (ADF), then returned to original pens. At the completion of study, carcass weight, backfat depth, and loin depth were collected. Data were analyzed with the fixed effects of dietary treatment by ANOVA, linear, and quadratic contrasts. Pen served as the experimental unit for performance and carcass characteristics and pig as the experimental unit for ATTD analyses. Overall, as SBH increased from 0% to 22.5%, ADG tended to decrease (linear P = 0.060) with no difference in ADFI (P &amp;gt; 0.05), resulting in an overall decrease in G:F (0.38, 0.37, 0.36, 0.35; linear P &amp;lt; 0.001; 0, 7.5, 15 and 22.5% SBH, respectively). Final BW tended to decrease (linear P = 0.069) and carcass weight decreased (102.9, 102.7, 99.7, and 96.5 kg, linear P &amp;lt; 0.001) as SBH increased in diet. Carcass fat depth (P = 0.014) and loin depth (P = 0.006) linearly decreased with increasing levels of SBH in the diet. Increasing levels of SBH from 0% to 22.5% decreased ATTD of GE and N (linear P &amp;lt; 0.001) and tended to increase ATTD NDF and ADF (linear P = 0.056 and P = 0.073, respectively). Altogether, these data suggest increasing dietary SBH in grow-finish pig diets decreases growth efficiency and the digestibility of GE and N. Further, feeding high inclusion rates of SBH negatively impacts carcass yield, backfat and loin depth.

PSV-16 Effect of precision feeding and functional amino acids on immune response and protein metabolism of growing pigs raised in poor sanitary conditions

Abstract The activation of the immune system reduces the nutrient availability for growth and increases the variability among pigs. Functional amino acids (AA) supplementation can reduce the negative effects of immune activation. Additionally, providing daily tailored diets using individual precision feeding (IPF) was shown to account for individual variability. Therefore, we hypothesized that the association of IPF and functional AA supplementation could reduce the negative effect of immune-challenged pigs fed with daily tailored diets. The aim of this study was to assess performance and blood parameters variation of growing pigs under poor sanitary conditions while being fed functional AA 120% above the estimated INRA AA ratios within IPF, compared with a conventional group-phase (GP) feeding system. The sanitary condition was characterized by oral inoculation of 2 × 109 cfu of Salmonella typhimurium and manure spreading on the pen floor on d 0. Sixty gilts (23 ± 2.8 kg body weight; BW) were distributed in a complete randomized block design in a 2 x 2 factorial arrangement composed of 2 diets: CN with 100% INRA AA ratio or AA+ with 120% of the ratio for Met, Thr and Trp; and 2 feeding systems: GP or IPF. GP pigs received a single diet matching the SID Lys requirement of the 80th-percentile pig at the beginning of the trial whereas IPF pigs received a diet tailored daily to each pig requirement. All pigs were group-housed and fed ad libitum for 28 d by automatic feeders. Body weight was measured at d 0 and 28 and feed intake was recorded daily. Blood samples were collected at d 0, 7 and 28. Data were analyzed with diet and feeding systems and their interactions as fixed effects and BW blocks as random effect. Blood parameters were analyzed as repeated measurements over time. The pig was considered the experimental unit. No diet effect or interactions were observed for any variable (P &amp;gt; 0.05), suggesting that only supplementing Met, Trp, and Thr is not enough to support growth during a sanitary challenge (Table 1). Haptoglobin and IgG increased linearly whereas IgA, urea, and creatinine had a quadratic increase over time (P &amp;lt; 0.05; Table 2). The IPF decreased growth performance and increased serum IgA and creatinine (P &amp;lt; 0.05), mostly due to the fact that IPF reduces AA provision compared with GP system. The IPF model, as most mathematical models, does not account for the AA and energy costs related to the immune challenge. Therefore, IPF might have underestimated the requirements of the pigs, and limited the amount of nutrients provided. In conclusion, the combined effect of IPF and functional AA supplementation was not able to reduce the negative effect of the sanitary challenge.

75 Diet acid-binding capacity-4 influences nursery pig performance and fecal dry matter

Abstract A total of 360 pigs (initial body weight = 5.9 kg) were used to evaluate the effects of increasing acid-binding capacity-4 (ABC-4) of the diet on nursery pig performance and fecal dry matter (DM). At weaning, pigs were allotted to 1 of 6 dietary treatments. There were 5 pigs/pen and 12 replications/treatment. Pigs were fed experimental diets in two phases with phase 1 from d 0 to 10 post-weaning followed by phase 2 from d 10 to 23. Diets were formulated with increasing ABC-4 levels ranging from 150 meq/kg (diet 1, low ABC-4) to 312 meq/kg (diet 5, high ABC-4) in phase 1 and 200 meq/kg (diet 1, low ABC-4) to 343 meq/kg (diet 5, high ABC-4) in phase 2. For diet 1, low ABC-4 diets were formulated using specialty soy protein concentrate (AX3 Digest; Protekta; Newport Beach, CA) at 12.5 and 10.0% of the diet in phase 1 and 2, respectively. The low ABC-4 diet also utilized fumaric and formic acid at 0.50 and 0.48% of the diet, respectively, for both phase 1 and 2. For diets 2 (medium low), 3 (medium), 4 (medium high), and 5 (high), increasing dietary ABC-4 was achieved by progressively decreasing the level of acidifiers and replacing specialty soy protein concentrate with enzymatically treated soybean meal (HP 300; Hamlet Protein; Findlay, OH) on an SID Lys basis. Diets 1 through 5 were formulated without the addition of pharmacological levels of Zn from ZnO. For diet 6, a positive control diet was used which had the same formulation as the highest ABC-4 diet but with the addition of 3,000 and 2,000 mg/kg of Zn from ZnO in phase 1 and 2, respectively. Following phase 2, all pigs were fed a common diet until d 38 of the study. In the experimental period and overall, there was a quadratic response observed (P ≤ 0.030) where body weight (BW) and average daily gain (ADG) were greatest for pigs fed the medium low and medium ABC-4 diets (Table). During the experimental period, increasing ABC-4 decreased (linear, P = 0.002) gain to feed ratio (G:F). For overall G:F, a quadratic response was observed (P = 0.023) where G:F was most improved for pigs fed the medium low and medium ABC-4 levels. For fecal DM, increasing ABC-4 decreased (linear, P ≤ 0.036) fecal DM on d 10 and 17, with no differences on d 23. Pigs fed the diet with pharmacological levels of Zn from ZnO had increased (P ≤ 0.038) ADG compared with pigs fed diets without ZnO during the experimental period and overall. In summary, a dietary ABC-4 level of 203 and 247 meq/kg for phase 1 and 2, respectively, was most beneficial to improve both growth performance and fecal DM in weanling pigs.

266 Evaluation of anchovy fish meal with or without added fish solubles on nursery pig performance

Abstract Two experiments were conducted in a commercial environment to evaluate anchovy fish meal with or without added anchovy fish solubles on nursery pig performance. In Exp. 1, pigs [n = 2,172; initial body weight (BW) = 5.2 kg] were randomly allotted to 1 of 6 dietary treatments. There were 25 or 27 pigs/pen and 14 replications/treatment. Dietary treatments were corn-soybean meal-based and consisted of: 1) diet containing 7.0% enzymatically treated soybean meal (HP 300; Hamlet Protein; Findlay, OH), 2) diet with 3.5% spray-dried bovine plasma (APC Inc, Ankeny, IA), 3) diet with 5.0% microbially enhanced soybean meal (MEPro, Prairie Aquatech, Brookings, SD), 4) diet with 5.2% microbially enhanced soybean meal with added anchovy fish solubles (TASA, Lima, Peru), 5) diet with 4.85% anchovy fish meal (TASA Prime, TASA, Lima, Peru), and 6) diet with 5.1% anchovy fish meal with added fish solubles (TASA Swine, TASA, Lima, Peru). In Exp. 2, pigs (n = 1,134; initial BW = 4.7 kg) were randomly allotted to 1 of 3 dietary treatments. There were 27 pigs/pen and 14 replications/treatment. Dietary treatments were corn-soybean meal-based consisting of a control diet containing enzymatically treated soybean meal at 7.0% of the diet, a diet containing 5.1% anchovy fish meal, and a diet containing 5.3% anchovy fish meal with added anchovy fish solubles. All protein sources in both trials were added on an SID Lys basis to maintain the same level of soybean meal across all dietary treatments. For both experiments, pigs were fed treatments for approximately 21 d in two phases based on feed budgets of 2.3 kg and 5.4 kg/pig in phases 1 and 2, respectively. For Exp. 1, diets contained 18.0 and 7.2% lactose for phase 1 and 2, respectively. For Exp. 2, diets contained 16.0 and 6.6% lactose for phase 1 and 2, respectively. Following experimental diets, all pigs were fed a common corn-soybean meal-based diet until the completion of the study. For Exp. 1, from d 0 to 21, pigs fed spray-dried bovine plasma or anchovy fish meal had increased (P &amp;lt; 0.05) average daily gain (ADG) and average daily feed intake (ADFI) compared with pigs fed anchovy fish meal with solubles with other treatments intermediate (Table). For Exp. 2, there were no differences in growth performance throughout the experimental period (d 0 to 21; P &amp;gt; 0.10); however, during the common period (d 21 to 42), pigs previously fed anchovy fish meal with added fish solubles had increased (P &amp;lt; 0.05) gain to feed ratio (G:F) compared with pigs fed the control diet with those fed anchovy fish meal alone intermediate. In conclusion, both experiments indicate anchovy fish meal can be used in nursery pig diets; however, further analysis is warranted to confirm the results of fish meal with solubles from Exp. 2.