Feed-grade Amino Acid Research Articles

105 Feed Additives That Optimize Nitrogen Bio-availability in Nursery Pigs Fed Reducing Crude Protein Diets

Abstract Reducing dietary crude protein in early nursery has been suggested as a way to conquer the challenge of post-weaning diarrhea. In order to meet the amino acid requirement in RCP diets, feed grade amino acids are typically used, but the detrimental effect on growth performance associated with the aggressive usage of these amino acids resulted in the establishment of dietary limits. Given the fact that protein deposition rate is the highest in young pigs, lower amino acid consumption could slow the growth rate and feed efficiency in early nursery phase. Therefore, identifying feed additives that increase nutrient retention not only can further reduce dietary nitrogen but also maintain GI tract health. Among all feed additives that exert improvements on nutrient digestibility, peptide and organic acids will be discussed here. Peptide, a di- tri amino acid, is absorbed more efficiently than free amino acids in the small intestine through a peptide transporter at the enteric site. In addition, aside from meeting the amino acid requirement, the bioactive peptide possesses functions such as antimicrobial, antioxidant, anti-inflammatory, and as a stimulated Peptide transporter associated with nutrient absorption. Hence, a dietary peptide can help pigs meet the nutrient requirement in RCP diets. Organic acids, on the other hand, have been found to lower gastric pH which improves nutrient absorption, alters microbiome structure (via bacteriostatic and bactericidal) and promotes the growth and health of animals. In addition, organic acids are a ready energy source which is especially critical since nutrient supply disruption, due to low intake during early weaning, is commonly found in weaning pigs. It is noteworthy that variations of growth-promoting effects do exist for both peptide and organic acid products. Thus, understanding the mode of action and response of dietary peptide and organic acid supplements when used across different farm settings is important to help producers decide when to transfer to an antibiotic-free, low zinc operation.

138 Effects of Increasing Soybean Meal in Corn-based Diets on Growth Performance of Late-finishing Pigs

Abstract Two experiments were conducted to determine the effects of increasing levels of soybean meal (SBM) replacing feed grade amino acids in corn or corn-dried distillers grains with solubles (DDGS)-based diets on growth performance of late finishing pigs. In both experiments, there were 22 to 27 pigs per pen and 14 pens per treatment. Average length of the experiments was 35 (Exp. 1) and 29 days (Exp. 2). Diets were balanced to contain 0.70% SID Lys and 2,667 or 2,610 kcal NE/kg for Exp. 1 and 2, respectively. Minimum amino acid ratios relative to Lys were: Ile, 55; Met&Cys, 60; Thr, 65; Trp, 19.5, and Val, 70. Dietary crude protein ranged from 10.1 to 15.2 for Exp. 1 and 13.6 to 19.4 for Exp. 2. The statistical model considered fixed effects of treatment, linear and quadratic contrasts, and random effect of block. In Exp.1, 1,793 pigs (L337×1050, PIC; initially 104.9 ± 1.4 kg) were fed corn-based diets and pens of pigs were assigned to 1 of 5 dietary treatments with increasing SBM from 5 to 20%. Overall, average daily gain (ADG) and gain-to-feed (G:F) increased (linear; P < 0.05) as SBM increased with the greatest improvement observed as SBM increased from 5 to 8.75%, with little improvement thereafter. In Exp. 2, 1,827 pigs (L337×1050, PIC; initially 97.9 ± 1.1 kg) were used in a similar study as Exp. 1, but all diets contained 25% DDGS and SBM levels increased from 0 to 16%. Overall, G:F and final bodyweight of pigs marginally improved (linear and quadratic, respectively; P < 0.10) as SBM increased, with the greatest performance observed when diets contained 8% SBM. These results suggest that increasing SBM up to 8% at the expense of feed grade amino acids in corn or corn-DDGS-based diets improved ADG or G:F in late-finishing pigs.

264 Effects of Low Dietary Crude Protein Diets Containing Coarse Wheat Bran as an Alternative to Zinc Oxide in Nursery Pig Diets

Abstract An experiment was conducted to determine the effect of reduced crude protein (CP) in diets containing coarse wheat bran (CWB) without pharmacological levels of Zn (ZnO) on growth performance and fecal dry matter (DM) of nursery pigs. A total of 650 pigs (DNA 241′600; initially 6.6 kg), were used with 5 pigs/pen and 26 replicate pens/treatment. Pens were assigned to 1 of 5 treatments in a RCB design based on BW. Treatments were fed for 13-d, contained 4% CWB, and consisted of: 1) diet with pharmacological ZnO (2,000 mg/kg Zn) and 21% CP formulated to 1.35% standardized ileal digestible (SID) Lys; 2) a diet with 110 ppm added Zn and 21% CP (1.35% SID Lys); 3) a diet with 110 ppm added Zn formulated to 18% CP (1.20% SID Lys); 4) an 18% CP diet with 110 ppm added Zn formulated to 1.35% SID Lys by the addition of increased levels of feed grade amino acids; and 5) diet 4 with addition of non-essential amino acids (NEAA; glycine and glutamic acid). Data were analyzed using the lmer function in R. Overall, pigs fed 21% CP with ZnO had increased (P < 0.05) ADG compared to those fed 18% CP (1.35% SID Lys) with high levels of feed grade amino acids or those fed the reduced SID Lys (1.2%) diet. Gain-to-feed ratio was increased (P < 0.05) for pigs fed 21% CP diets and those fed the 18% CP diet with NEAA compared to pigs fed 1.2% SID Lys and pigs fed high levels of feed grade amino acids. Fecal DM was increased (P < 0.05) for pigs fed reduced SID Lys diet. In conclusion, reducing CP (subsequently SID Lys) in diets without ZnO decreased growth performance but increased fecal DM.

215 Effects of Increasing Dietary Standardized Ileal Digestible Lysine Levels on Growth Performance of 39- to 119-kg Pigs Sired by High Index Boars

Abstract Our objective was to determine the effects of increasing dietary standardized ileal digestible (SID) lysine (Lys) on the growth performance of grow-finish pigs. A total of 1,120 pigs (PIC 337×Camborough, initially 39.0±0.82 kg) were used in a 77-d study. Pigs used in the study were sired by boars ranked in the top 15% of a selected PIC elite boar stud based on index. Pens of pigs were blocked by body weight and randomly allotted to 1 of 5 treatments, which consisted of 85, 95, 105, 115, and 125% of the PIC2016 SID Lys recommendations within each phase. Diets were corn-soybean meal-based and formulated to be iso-caloric. Treatments were achieved with increasing feed-grade amino acids. There were 9 mixed-gender pens per treatment and 24 or 25 pigs per pen. Data were analyzed using generalized linear and nonlinear mixed models with pen as the experimental unit. Competing models included linear, quadratic polynomial (QP), broken-line linear (BLL), and broken-line quadratic (BLQ). Increasing dietary SID Lys from 85 to 125% marginally improved overall average daily gain (ADG, quadratic, P = 0.056), gain to feed ratio (G:F, quadratic, P = 0.062), and final body weight (linear, P = 0.075). There was no evidence for treatment effects on mortality and removals (P > 0.10). The best-fitting models for ADG were QP and BLL. The QP model estimated the maximum ADG at 110.6% (95% CI: 93 to >125%), with 99% of maximum ADG achieved at 97.4%. The BLL plateau was estimated at 105.0% (95% CI: 74 to 136%). The best-fitting model for G:F was QP, estimating the maximum G:F at 107.8% (95% CI: 92 to >125%). In conclusion, the estimated optimum overall SID Lys for 39- to 119-kg pigs sired by high index boars ranged from 105.0 to 110.6% of PIC2016 SID Lys recommendation within each phase, depending on the response criteria and statistical model.

168 Effects of Increasing Dietary Standardized Ileal Digestible Lysine Levels on Growth Performance of 12- to 26-kg Pigs Sired by High Index Boars

Abstract Our objective was to determine the effects of increasing dietary standardized ileal digestible (SID) lysine (Lys) on the growth performance of late nursery pigs. A total of 1,125 pigs (PIC 337×Camborough, initially 12.0±0.66 kg) were used in a 21-d study. The pigs used in the study were sired by boars ranked in the top 15% of a selected PIC elite boar stud based on index. Pens of pigs were blocked by body weight and randomly allotted to 1 of 5 treatments containing 0.95, 1.10, 1.20, 1.35, and 1.50% of SID Lys. Diets were corn-soybean meal-based and contained 2,480 Kcal of NE/kg. Treatments were achieved with increasing feed-grade amino acids. There were 9 mixed gender pens per treatment and 25 pigs per pen. Data were analyzed using generalized linear and nonlinear mixed models with pen as the experimental unit. Competing models included linear, quadratic polynomial (QP), broken-line linear (BLL), and broken-line quadratic (BLQ). Increasing SID Lys concentration improved average daily gain (ADG, linear, P < 0.001) and gain to feed ratio (G:F, quadratic, P = 0.011). The best-fitting models for ADG were QP and BLL. The QP model estimated the maximum ADG at 1.43% (95% CI: 1.12 to >1.50%), with 99% of maximum ADG achieved at 1.27%. The BLL plateau was estimated at 1.31% (95%CI: 1.06 to >1.50%). The best-fitting models for G:F were QP, BLL, and BLQ. The QP model estimated the maximum G:F at 1.48% (95%CI: 1.23 to >1.50%), with 99% of maximum G:F achieved at 1.24%. The BLL plateau was estimated at 1.30% (95% CI: 1.18 to 1.41%), whereas the BLQ plateau was estimated at 1.36% (95%CI: 1.14 to >1.50%). In conclusion, the estimated optimum SID Lys concentration for 12- to 26-kg pigs sired by high index boars ranged from 1.30 to 1.48%, depending on the response criteria and statistical model.

Effects of feeding diets containing low crude protein and coarse wheat bran as alternatives to zinc oxide in nursery pig diets.

Two experiments were conducted to determine the effects of crude protein (CP) level in diets containing coarse wheat bran (CWB) with or without pharmacological levels of Zn (provided by zinc oxide: ZnO) on growth performance and fecal DM of nursery pigs. In experiment 1, 360 barrows (Line 200 × 400, DNA, Columbus, NE, initially 5.6 kg) were allotted to 1 of 6 dietary treatments from d 0 to 21 after weaning with 5 pigs per pen and 12 pens per treatment. Treatments included a positive control diet (21% CP) with 3,000 mg/kg Zn in phase 1 and 2,000 mg/kg in phase 2; negative control (21% CP) with 110 mg/kg added Zn, and 4 diets containing 4% CWB and 110 mg/kg added Zn formulated to contain 21%, 19.5%, 18%, or 16.5% CP. The 2 control diets and 21% CP CWB diet contained 1.40% standardized ileal digestible (SID) Lys in phase 1 and 1.35% SID Lys in phase 2, while the 19.5%, 18%, and 16.5% CP diets contained 1.33, 1.25 and 1.20% Lys, respectively, in both phases. Pigs fed the positive control diet containing pharmacological ZnO had increased (P < 0.05) ADG and G:F compared with the negative control and the 21% CP CWB diet. Reducing CP (concurrently with SID Lys) in diets containing CWB decreased ADG and G:F (linear, P = 0.002); however, fecal DM increased (linear, P = 0.005). In experiment 2, two groups of 300 and 350 pigs, initially 7.0 and 6.2 kg, respectively, were used with 5 pigs per pen and 26 pens per treatment. The objective was to determine if adding back essential AA would improve growth performance of pigs fed the low CP diets. All dietary treatments were fed for 13 days, contained 4% CWB, and consisted of: (1) positive control with 2,000 mg/kg of Zn and 21% CP (1.35% SID Lys); (2) no ZnO and 21% CP; and 3 diets with no ZnO formulated to 18% CP and (3) 1.2% SID Lys; (4) 1.35% SID Lys by the addition of feed grade amino acids (AA), and (5) diet 4 with non-essential amino acids (NEAA; Gly and Glu). Pigs fed 21% CP with ZnO had increased (P = 0.001) ADG compared to those fed 18% CP (1.35% SID Lys) with high levels of feed grade amino acids or those fed the reduced SID Lys (1.2%) diet. Overall, G:F was improved (P < 0.001) for pigs fed 21% CP diets and those fed the 18% CP diet with NEAA compared to pigs fed 1.2% SID Lys and pigs fed high levels of feed grade amino acids. Fecal DM was increased for pigs fed the reduced SID Lys diet. In summary, pharmacological levels of Zn improve pig growth performance, but reducing CP (and subsequently SID Lys) decreased nursery pig growth performance.

Effects of high-protein distillers dried grains on growth performance of nursery pigs.

A total of 300 pigs (DNA 400 × 200, Columbus, NE), initially 11.1 kg, were used in a study to evaluate the effects of increasing amounts of high-protein distillers dried grains (HP DDG) on growth performance and to estimate its energy value relative to corn. Pigs were weaned, placed in pens with five pigs each, and fed a common diet for 21 d after weaning. Then, pens were assigned to treatments in a randomized complete block design. There were 5 treatments with 12 replicates per treatment. Treatments consisted of 0, 10, 20, 30, or 40% HP DDG, formulated by changing only the amounts of corn and feed-grade amino acids. Pigs were weighed weekly for 21 d to evaluate average daily gain (ADG), average daily feed intake (ADFI), and gain-to-feed ratio (G:F). Caloric efficiency was obtained by multiplying ADFI by kcal of net energy (NE) per kg of diet and dividing by ADG. The NE values for corn and soybean meal were obtained from NRC (2012), and initial estimates for HP DDG NE were derived from the Noblet et al. (1994) equation. The energy of HP DDG was estimated based on caloric efficiency relative to the diet without HP DDG. Pigs fed diets with increasing HP DDG had a linear decrease (P < 0.01) in ADG, ADFI, and final body weight. There was a tendency for a quadratic response (P = 0.051) in G:F, with the greatest G:F observed for pigs fed diets with 40% HP DDG. There was a linear reduction (P < 0.05) in caloric efficiency with increasing amounts of HP DDG, indicating the initial NE estimate of HP DDG was underestimated. The use of caloric efficiency to estimate the energy value of HP DDG presents several limitations. This approach assumes that the NE values of corn and soybean meal are accurate and does not take into account possible changes in body composition, which can influence the G:F response as leaner pigs are more efficient. In conclusion, increasing HP DDG in the diet linearly decreased ADG and ADFI. Using caloric efficiency to estimate energy content relative to corn, the HP DDG used in this study was estimated to be 97.3% of the energy value of corn. Direct or indirect calorimetry is needed to confirm this value.

Influence of Feed Grade Amino Acid Inclusion Level in Late Nursery and Grower Diets Fed to Pigs from 21 to 75 lb

Influence of Feed Grade Amino Acid Inclusion Level in Late Nursery and Grower Diets Fed to Pigs from 21 to 75 lb

128 Determining the effects of high phytase levels and feeding duration on growth performance and carcass characteristics of growing-finishing pigs

Abstract Our objective was to determine the effects of high phytase levels and feeding duration on performance of growing finishing pigs. A total of 1,215 barrows and gilts (PIC 359×Camborough, initially 28.0±0.47 kg) were used in a 126-d growth trial with 27 pigs per pen and 15 pens per treatment in a randomized complete block design. Diets were corn-soybean meal-dried distillers grains with solubles-based.Treatments were: 1) Control (no added phytase); 2) Grower phytase (1,500 FYT/kg added phytase fed from d 0 to 57, then no phytase from d 57 to market); and 3) Grow-finish phytase (1,500 FYT/kg added phytase fed throughout the study). Phytase (Ronozyme Hiphos GT 2500, heat-stable; DSM Nutritional Products, Inc., Parsippany, NJ) was assumed to release 0.146% digestible phosphorus (P), 0.166% available P, 0.102% STTD calcium, 53 kcal/kg of metabolizable energy, 42 kcal/kg of net energy (NE), and 0.0217, 0.0003, 0.00886, 0.0224, 0.0056, 0.0122, and 0.0163% standardized ileal digestible lysine, methionine, methionine+cysteine, threonine, tryptophan, isoleucine, and valine, respectively. Beef tallow and feed grade amino acids (AA) were added to the diets without phytase to balance NE and AA across treatments. Data were analyzed using generalized linear mixed models with pen as the experimental unit.Overall, pigs fed diets with no phytase and pigs that were only fed phytase in the grower period had greater (P&amp;lt; 0.05) average daily gain (ADG) and feed efficiency (G:F) than pigs fed the phytase-containing diets until market. Pigs fed the control and grower phytase treatments had greater (P&amp;lt; 0.10) hot carcass weight (HCW) than the phytase throughout treatment. No evidence of differences (P &amp;gt;0.10) were observed for other carcass characteristics. In summary, adding 1,500 FYT/kg of phytase and using full matrix values for minerals, AA, and energy had detrimental effects on ADG, G:F, and HCW in this study when applied to the entire grow-finish period.

17 Challenges and implications of feeding diets with excess concentrations of leucine to growing-finishing pigs

Abstract Excess dietary leucine stimulates the key enzymes involved in branched-chain catabolism causing breakdown of all branched-chain amino acids, including isoleucine and valine. Branched-chain amino acids share a common brain transporter with other large neutral amino acids (LNAA). Excess levels of one of the LNAA increases brain uptake of that amino acid and decreases the uptake of the other LNAA, including tryptophan. Thus, excess leucine can impact the requirements for many amino acids. From a practical basis, this effect was first demonstrated with diets containing blood meal, but was thought to be of limited concern unless high blood meal diets were fed. Use of corn dried distillers grains with solubles (DDGS) or high protein DDGS in corn-based diets results in diets containing excess leucine. These high leucine levels are of limited concern if adequate levels of other branched-chain amino acids and LNAA are fed, which is often the case if the diet consists largely of intact protein sources. Feed grade amino acids, such as L-lysine, L-threonine, L-tryptophan, DL-methionine, L-valine, and L-isoleucine have been widely adopted as a means to lower nitrogen excretion and diet cost. Including these amino acids in diets containing corn products reduces dietary leucine; but the resulting diets are formulated near the requirement for the first 6 limiting amino acids, including valine, isoleucine, and tryptophan, while still being high in leucine. The excess leucine increases the requirements for valine, isoleucine, and possibly other LNAA, such as tryptophan and possibly others. The exact relationship between these amino acids and how to handle them in practical diet formulation is still being elucidated; however, recent meta-analysis and experimental data confirm the importance of these ratios and provide useful direction for future research.

266 Dietary strategies in diets without zinc oxide for nursery pigs

Abstract A total of 300 pigs (DNA 241 × 600; initially 4.2 kg) were used to evaluate the effects of different nutritional strategies to replace zinc oxide (ZnO) in nursery diets. Treatments consisted of A) Positive control (21% CP; ZnO providing 3,000 ppm Zn from d 0 to 7, and 2,000 ppm Zn from d 7 to 25); B) Negative control (NC; no ZnO); C) NC plus 1.2% Na diformate; D) NC with 4% coarse ground wheat bran; E) NC with low crude protein (18%) by adding high levels of feed grade amino acids; and F) the combination of NC with 18% crude protein (CP), 1.2% Na diformate, and 4% coarse ground wheat bran. There were 5 pigs per pen and 10 pens per treatment in a completely randomized design. Data were analyzed with the Proc Mixed procedure in SAS. For the overall period (d 0 to 46), pigs fed diets containing ZnO had greater (P &amp;lt; 0.001) ADG, ADFI, and final BW than other treatments, with pigs fed the NC with 18% CP having the lowest performance. Pigs fed the NC diet without any nutritional alternative had the lowest fecal dry matter (DM; P &amp;lt; 0.050) and highest fecal scores (P &amp;lt; 0.050). Pigs fed diets with ZnO had similar fecal DM and scores as pigs fed the diet containing the combination of 1.2% Na diformate, 4% coarse ground wheat bran, and low (18%) CP, but greater (P &amp;lt; 0.023) fecal DM than pigs fed the alternatives used individually. This study suggests none of the strategies used alone were effective at replacing ZnO while the use of low CP and amino acids reduced performance further. Combining the three alternatives tested as a replacement to ZnO improved fecal DM content and fecal score but did not result in improved growth performance.

164 Evaluation of the energy value of soybean meal relative to corn based on growth performance of 11- to 22-kg pigs

Abstract A 21-d experiment was conducted to estimate the energy value of soybean meal (SBM) and determine the effects of increasing SBM on pig performance. A total of 2,233 pigs (PIC 337 × 1050), initially 11.0 kg, were placed in pens containing 20 to 27 pigs. Treatments were assigned in a randomized complete block design with BW as blocking factor. Dietary treatments consisted of 21, 27, 33, or 39% SBM obtained by changing the amount of feed-grade amino acids and corn. There were 23 replicates per treatment. Pigs were weighed and feed disappearance measured to calculate ADG, ADFI, G:F, and caloric efficiency (CE). Cull pigs and mortality were evaluated daily. Data were analyzed with the GLIMMIX procedure of SAS. There was a tendency (P = 0.090) for a quadratic response for ADG, with a decrease in ADG observed with 39% SBM. There was a tendency (linear, P = 0.092) for a decrease in ADFI as SBM increased. Pigs fed diets with increasing SBM had a tendency (quadratic, P = 0.069) for an increase in G:F up to 33% SBM and an improvement (linear, P = 0.001; quadratic, P = 0.063) in CE with increasing SBM. There was no evidence for differences (P ≥ 0.457) in cull pigs and mortality. Using CE to estimate the energy of SBM relative to corn, a value of 105.4% of corn energy or 2,816 kcal/kg NE was determined using all data points. When removing the CE value of the 39% SBM treatment due to the quadratic tendency, SBM was estimated to have 121.1% of corn energy or 3,236 kcal/kg NE. The results suggest that feeding increasing levels of SBM improves G:F and CE. The energy value of SBM was estimated between 105 and 121% of corn, which is much greater than the NRC (2012) would suggest.

Estimate of the energy value of soybean meal relative to corn based on growth performance of nursery pigs

BackgroundTwo experiments were conducted to determine the effects of increasing amounts of soybean meal (SBM) in swine diets and estimate the energy value of SBM.MethodsA total of 2233 pigs (PIC 337 × 1050, Hendersonville, TN) and 3796 pigs (PIC 359 × C40), initially 11.0 kg and 17.6 kg body weight (BW), were used in Exp. 1 and 2, respectively. In Exp. 1, pigs were placed in 92 pens each containing 20 to 27 pigs. In Exp. 2, pigs were placed in 84 pens each containing 37 to 43 pigs. Treatments were assigned in a randomized complete block design with BW as the blocking factor. Dietary treatments consisted of 21%, 27%, 33%, or 39% SBM in Exp. 1 and 17.5%, 22%, 26.5%, 31%, 35.5%, or 40% SBM in Exp. 2, obtained by changing the inclusion rate of feed-grade amino acids and corn grain. For Exp. 1, representative samples of corn grain, SBM, and distillers dried grains with solubles were analyzed for total AA content prior to diet formulation. For Exp. 2, diets were formulated using NRC (2012) nutrient loadings. Treatment diets were fed for 21 and 22 d (Exp. 1 and 2) and there were 23 replicates in Exp. 1 and 14 replicates in Exp. 2. Pigs were weighed and feed disappearance measured weekly to calculate average daily gain (ADG), average daily feed intake (ADFI), gain-to-feed ratio (G:F), and caloric efficiency (CE). Data were analyzed with block as a random effect and treatment as a fixed effect, and contrasts were constructed to test the linear and quadratic effects of increasing SBM.ResultsIn Exp. 1, there was a tendency (linear, P = 0.092) for a decrease in ADFI as SBM increased. There was a tendency (P = 0.090) for a quadratic response for ADG, with a decrease in ADG observed with 39% SBM inclusion. Pigs fed diets with increasing SBM had a tendency (quadratic, P = 0.069) for an increase in G:F up to 33% SBM and an improvement (linear, P = 0.001; quadratic, P = 0.063) in CE with increasing SBM. Using CE to estimate the energy of SBM relative to corn, a value of 105.4% of corn energy or 2816 kcal/kg NE was determined using all data points. When removing the CE value of the 39% SBM treatment due to the quadratic tendency, SBM was estimated to have 121.1% of corn energy or 3236 kcal/kg NE. In Exp. 2, there was a decrease (linear, P = 0.001) in ADFI. Pigs fed increasing SBM had a tendency (linear, P = 0.065) for reduced ADG but an improvement (linear, P = 0.001) in G:F and CE as SBM increased. The energy value of SBM was estimated as 124.7% of corn energy or 3332 kcal/kg NE.ConclusionsThe results suggest that feeding increasing levels of SBM improves G:F and CE. The energy value of SBM was estimated to be between 105% and 125% of corn, which is much greater than the NRC (2012) would indicate.

Nutritional evaluation of different varieties of sorghum and the effects on nursery pig growth performance.

Five experiments were conducted to determine the standardized total tract digestibility (STTD) of P, digestible energy (DE), metabolizable energy (ME), and standardized ileal digestibility (SID) of amino acids (AA) in three sorghum varieties compared with corn and to determine the effects of sorghum varieties on nursery pig growth. In exp. 1, 48 barrows (initially 18.6 kg) were housed individually in metabolism crates. Treatments were arranged in a 2 × 4 factorial evaluating two levels of microbial phytase (0 or 500 units/kg) and four grain sources (corn, high-lysine, red, or white sorghum). Added phytase improved (P < 0.05) STTD of P in all ingredients, but was not different among the grains. In exp. 2, the DE and ME in the three sorghum varieties were not different from corn. In exp. 3, 10 growing barrows (initially 25.9 kg) with a T-cannula in the terminal ileum were used. Standardized ileal digestible Lys, Met, Thr, and Val were greater (P < 0.05) in corn than in the sorghum-based diets with no differences among the sorghum varieties. In exp. 4, 160 pigs (initially 6.3 kg) were randomly allotted to one of four dietary treatments with five pigs per pen and eight replicate pens per treatment in a 20-d experiment. Dietary treatments included corn or the three sorghum varieties, where the varieties of sorghum replaced corn on an SID Lys basis. No differences among treatments were observed in any growth performance parameters. In exp. 5, treatments consisted of a corn-based diet, a diet based on conventional sorghum (a mixture of red and white sorghum), and four diets with high-lysine sorghum containing increasing amounts of feed-grade AA, replacing soybean meal. Overall, pigs fed the high-lysine sorghum diet with the greatest amount of added feed-grade AA had the poorest gain:feed ratio (G:F; P < 0.05) compared with pigs fed all the other experimental diets. Within those fed the high-lysine sorghum and feed-grade AA, average daily gain, final body weight (linear, P < 0.10), and G:F (linear, P < 0.01) decreased as feed-grade AA increased. In summary, no differences in STTD of P or in DE and ME were observed among the grain sources. The SID AA values for the three sorghum varieties were not different; however, they were all lower than for corn. These results indicate that these varieties of sorghum can successfully replace corn in nursery pig diets if diets are formulated to account for differences in AA digestibility.

Effects of amino acid biomass or feed-grade amino acids on growth performance of growing swine and poultry.

Three experiments were conducted to determine the effect of three fermented amino acids (AA) with their respective biomass compared to crystalline AA on the growth performance of swine and poultry. In experiment 1, 315 barrows (DNA 200 × 400, initially 11.3 ± 0.69 kg) were allotted to 1 of 4 dietary treatments with 5 pigs per pen and 15 or 16 pens per treatment. Dietary treatments included a negative control (16% standardized ileal digestible [SID] Tryptophan:lysine [Trp:Lys] ratio), positive control (21% SID Trp:Lys ratio from crystalline Trp), or diets containing Trp with biomass to provide 21 or 23.5% SID Trp:Lys ratios, respectively. Pigs fed the positive control or low Trp with biomass diet had increased (P < 0.05) ADG compared to pigs fed the negative control diet, with pigs fed the high Trp with biomass diet intermediate. Pigs fed the low Trp with biomass diet had increased (P < 0.05) G:F compared to the negative control diet, with others intermediate. In experiment 2, 1,320 1-d-old male broilers (Cobb 500, initially 45.2 g) were allotted to one of four dietary treatments with 33 birds per pen and 10 pens per treatment. Dietary treatments included a negative control (58/58% Threonine:lysine [Thr:Lys] ratio), positive control (65/66% Thr:Lys ratio from crystalline Thr), or diets containing Thr with biomass to provide 65/66 or 69/70% Thr:Lys ratios in starter and grower diets, respectively. Broilers fed the positive control or Thr with biomass diets had increased (P < 0.05) ADG compared to broilers fed the negative control diet. Broilers fed the positive control or the low Thr with biomass diet had increased (P < 0.05) G:F compared to the negative control and high Thr with biomass treatments. In experiment 3, 2,100 one-day-old male broilers (Cobb 500, initially 39.4 g) were allotted to one of four dietary treatments with 35 birds per pen and 15 pens per treatment. Dietary treatments included a negative control (59/63% Valine:lysine [Val:Lys] ratio), positive control (75/76% Val:Lys ratio from crystalline Val), or diets containing Val with biomass to provide 75/76 or 84/83% Val:Lys ratios in starter and grower diets, respectively. Broilers fed the positive control or Val with biomass diets had increased (P < 0.05) ADG, ADFI, and G:F compared to those fed the negative control diet. In conclusion, Trp, Thr, or Val with their respective biomass appear to be equally bioavailable and a suitable alternative to crystalline AA in swine and poultry diets.

PSVI-20 Evaluating the productive energy content of high-protein distillers dried grains in swine diets

Abstract A total of 300 pigs (DNA 400×200; initially 11.1 kg) were used in a 21-d trial to determine the effects of increasing levels of high-protein distillers dried grains (HP DDG) on pig performance and to estimate the productive energy of HP DDG. Pens with 5 pigs each were assigned to treatments in a randomized complete block design with 12 replicates per treatment. Treatments included diets with 0, 10, 20, 30, or 40% HP DDG formulated by changing corn and feed-grade amino acid levels. Caloric efficiency was obtained by multiplying ADFI by dietary net energy (NE) and dividing by ADG. The NE of HP DDG was estimated at 1,914 kcal/kg by using Noblet et al. (1994) equation and NRC (2012) values were used for corn. Productive energy was estimated based the average caloric efficiency of the HP DDG diets relative to the diet without HP DDG. Data were analyzed with the GLIMMIX procedure of SAS with pen as the experimental unit and block as random effect. Pigs fed diets with increasing HP DDG had a linear decrease (P &lt; 0.01) in ADG and ADFI and a tendency (P = 0.051) for a quadratic response in G:F. There was a linear improvement (P &lt; 0.01) in caloric efficiency with increasing HP DDG (3,876, 3,753, 3,676, 3,520, and 3,300 kcal/kg, respectively). The productive energy of HP DDG was estimated as 2,686 kcal/kg or 97.3% of corn NE. In summary, high levels of HP DDG negatively impacted growth performance. The equation used to estimate NE of HP DDG resulted in underestimated values. The productive energy of HP DDG is approximately 97% of corn NE.

Digestible lysine concentrations and amino acid densities influence growth performance and carcass traits in broiler chickens from 14 to 35 days post-hatch

The present study was conducted to evaluate the responses of growth performance and carcass traits in Cobb MV × 500 fast feathering broiler chickens fed maize, soybean meal (SBM) and peanut meal based diets containing different levels of digestible (dig) lysine (Lys). Dietary treatments consisted of 6 concentrations of dig Lys that ranged from 8.4 to 12.9 g/kg in increments of 0.9 g/kg. Two control diets with the medium level of dig Lys concentration of 11.1 g/kg were included where the positive control (PC) diet was a typical commercial diet based on maize and SBM and the negative control (NC) diet replaced part of SBM with100 g/kg peanut meal to allow higher supplementations of feed grade amino acids. Each of the eight experimental diets were offered to either male or female broiler chickens to form 16 experimental treatments and each treatment included 6 floor pens with 12 birds per pen. Broiler chickens were offered experimental diets from 14 to 35 days post-hatch. All diets were balanced with essential amino acids (EAA) by using ideal protein ratio approach and were offered to broiler chickens from 14 to 35 days post-hatch. Predictably, male broiler chickens had better weight gain (WG), feed intake (FI), feed conversion ratio (FCR) and breast meat yield (P < 0.001) than female birds. Sex did not influence yield of wings (P = 0.174) and thighs (P = 0.243). There were no interactions between sex and dietary dig Lys levels on growth performance and linear improvements were observed for live body weight (BW), WG and FCR. By comparing three mathematical models, in female birds, the dig Lys requirement was estimated at 11.5 g/kg for optimal WG and 12.1 g/kg for FCR. In male broiler chickens, the dig Lys requirement was estimated at 10.3 g/kg for optimal WG and 12.2 g/kg for FCR. The results suggested that modern broilers are highly responsive to dietary amino acid (AA) density and regular evaluations of AA requirements are needed because of genetic progress of modern broiler chickens.

Effects of standardized ileal digestible histidine to lysine ratio on growth performance of 7- to 11-kg nursery pigs.

Histidine may be the sixth limiting amino acid (AA) in practical nursery diets supplemented with high amounts of feed-grade AA. Therefore, 2 experiments were conducted to determine the standardized ileal digestible (SID) His:Lys ratio requirement estimate for growth performance of 7- to 11-kg nursery pigs. A total of 360 and 350 pigs (DNA 241 × 600, Columbus, NE; initially 7.1 ± 0.31 and 6.6 ± 0.36 kg) were used in Exp. 1 and 2, respectively. There were 5 pigs per pen with 12 replicates per treatment in Exp. 1 and 10 replicates per treatment in Exp. 2. After weaning, pigs were fed a common pelleted diet for 10 d in Exp. 1 and 7 d in Exp. 2. Then, pens were assigned to treatments in a randomized complete block design with body weight (BW) as the blocking factor. Dietary treatments consisted of SID His:Lys ratios of 24%, 28%, 32%, 36%, 40%, and 44% in Exp. 1 and 24%, 28%, 30%, 32%, 34%, 36%, and 42% in Exp. 2. Experimental diets were fed in pellet form for 10 or 14 d in Exp. 1 and 2, followed by a common mash diet for 15 or 14 d, respectively. Data were analyzed using the GLIMMIX and NLMIXED procedures of SAS, fitting data with heterogeneous variance when needed. The competing statistical models utilized were quadratic polynomial, broken-line linear (BLL), and broken-line quadratic. In Exp. 1, increasing SID His:Lys ratio increased (quadratic, P = 0.001) ADG, ADFI, G:F, and day 10 BW. In Exp. 2, ADG, G:F, and day 14 BW increased (quadratic, P = 0.001), and ADFI increased linearly (P = 0.001) with increasing SID His:Lys ratio. The best-fitting model for all response variables analyzed was the BLL. In Exp. 1, requirement estimates were 29.7%, 29.1%, and 29.8% SID His:Lys ratio for ADG, ADFI, and G:F, respectively. In Exp. 2, the SID His:Lys ratio requirement estimates were 31.0% for ADG and 28.6% for G:F. These results suggest that the SID His requirement estimate for growth performance is no more than 31% of Lys and that the NRC (2012) SID His requirement of 34% of Lys may be overestimated for 7- to 11-kg pigs.

344 Evaluation of Supplementation of Potassium Chloride and Choline Chloride in High Feed Grade Amino Acid Finishing Diets.

344 Evaluation of Supplementation of Potassium Chloride and Choline Chloride in High Feed Grade Amino Acid Finishing Diets.

The use of feed-grade amino acids in lactating sow diets

BackgroundThe use of feed grade amino acids can reduce the cost of lactation feed. With changing genetics, increasing feed costs, and higher number of pigs weaned with heavier wean weights further evaluation of higher inclusion levels of feed-grade amino acid in lactation diets than previously published is warranted. Two experiments (Exp.) were conducted to determine the optimal inclusion level of L-lysine HCl to be included in swine lactation diets while digestible lysine levels remain constant across dietary treatments and allowing feed grade amino acids to be added to the diet to maintain dietary ratios relative to lysine to maximize litter growth rate and sow reproductive performance. Furthermore, the studies were to evaluate minimal amino acid ratios relative to lysine that allows for optimal litter growth rate and sow reproductive performance.ResultsExp. 1: Increasing L-lysine HCl resulted in similar gilt feed intake, litter, and reproductive performance. Average litter gain from birth to weaning was 2.51, 2.49, 2.59, 2.43, and 2.65 kg/d when gilts were fed 0.00, 0.075, 0.150, 0.225, and 0.30% L-lysine HCl, respectively. Exp. 2: The average litter gain from birth to weaning was 2.68, 2.73, 2.67, 2.70, and 2.64 kg/d (P < 0.70) when sows were fed 0.1, 0.2, 0.3, 0.4, and 0.4% L-lysine HCl plus valine, respectively. No other differences among dietary treatments were observed.ConclusionsCollectively, these studies demonstrate corn-soybean meal based lactation diets formulated with a constant SID lysine content for all parities containing up to 0.40% L-lysine HCl with only supplemental feed grade threonine and a methionine source have no detrimental effect on litter growth rate and subsequent total born.