Supplementation of multi-carbohydrase enzyme cocktails can increase nutrient digestibility of fibrous diets in grower pigs, particularly acting on dietary non-starch polysaccharides (NSP). Although NSP degrading enzymes are extensively used in sow diets, there is little data characterizing the NSP enzyme effects. Our previous work demonstrated a 10% increase in nutrient digestibility in diets fed to gestating sows. The objective of this study was to evaluate the effect of a carbohydrase mixture (CM) and dietary fiber level on standardized ileal digestibility (SID) of protein and amino acids (AA) and apparent ileal digestibility (AID) of NSP in gestation diets fed to pregnant sows. Ileal cannulas were placed in 12 gestating sows (parity 0 to 2) who were allowed to recover for 1 week, then assigned to either a high (HF; 17.5% NDF) or low fiber (LF; 10% NDF) diet with one of 3 levels of CM supplementation (‘0’, ‘0.08’, and ‘0.10’%) or a nitrogen-free diet to determine ileal endogenous AA losses. Diets were corn-soybean meal based with soyhulls and corn DDGS as fiber sources and formulated to reflect industry-relevant diets. Thus, oil was included at 3% in HF to maintain similar formulated metabolizable energy content. Sows were fed once daily at 2.2 kg/d. Ileal digesta samples were collected for 12h on 2 successive days following a 7-day adaption period. At the end of digesta collection, sows were assigned a different diet in a new adaptation/digesta collection period. There were 5 collection periods for a total of 8 observations/diet. Digesta was analyzed for crude protein, amino acids, NSP, and titanium as the indigestible marker to determine AID and SID. There was no interaction between diet fiber level and CM supplementation. Carbohydrase mixture supplementation to gestating sow diets did not impact SID of crude protein and AA regardless of dietary fiber level. The SID of His, Ile, Lys, Phe, Thr, Trp, and Val were 3 to 6% lower (P < 0.09) in HF than LF independent of CM. There was no impact of fiber level on the average SID of amino acids in gestating sow diets which was 83.5%. Supplementation of CM did not impact AID of NSP components, but sows fed HF had higher AID of arabinose (LF: 26.5% vs HF: 40.6%), xylose (LF: 3.5% vs HF: 40.9%), and total NSP (LF: 25.9% vs HF: 40.0%) compared to sows fed LF (P < 0.05).
Article Quarter: FY23 Q3
Investigating the impact of fiber type and multicarbohydrase supplementation on nutrient digestibility and energy balance of gestating sows
Supplementing fiber-degrading enzymes in grow-finish pig diets has been shown to improve energy and nutrient digestibility. However, there is a paucity of research on their effectiveness in gestation diets. The experimental objective was to evaluate the efficacy of multicarbohydrase supplementation in the presence of soluble (20% sugar beet pulp) and insoluble (20% corn DDGS) dietary fiber sources on the apparent total tract digestibility (ATTD) of nutrients and energy balance of sows at mid- and late-gestation. A total of 36 confirmed gestating sows (186±4.6 kg BW) were blocked by parity randomly assigned to 1 of 4 diets (n=8) in a 2×2 factorial arrangement of treatments on d 28 of gestation. Factors included fiber type of insoluble (IF; 16.91 IDF%) or soluble fiber (SF; 5.26 SDF%) and with (+) or without (–) enzyme supplementation (0.05%, Rovabio Advance P10; Adisseo, Antony, France). Diets were fed from d 28 to 109 of gestation at a feeding level of 2.1 kg (SID-Lys 11 g/d and 4.5 NE-Mcal/d). Diets contained 0.5% of TiO2. Two separate 9-d metabolism periods were conducted on d 50-59 (mid-) and 99-108 (late-) of gestation. During each period, d 1-3 served as an environmental adaptation period, d 4-7 total urine and feces were collected (96-h) and followed by a 48-h lactulose-mannitol study. Data were analyzed as repeated records using a linear mixed model with block as a random effect, and fiber type, enzyme, and period and their interactions as fixed effects. Multicarbohydrase supplementation increased the ATTD of GE, DM, and NDF by 2.8%, 3.4%, and 8.3%, respectively (Enzyme P<0.05). There was a tendency for a Period × Fiber × Enzyme interaction for the ATTD of ADF, whereas multicarbohydrase supplementation with SF increased ADF digestibility in mid-gestation by 6.5%, but not in late gestation (P=0.051). Compared to IF-, the ATTD of hemicellulose was 5.3% greater in sows fed IF+ but did not differ from SF- and SF+ (Fiber×Enzyme P</em>=0.037). Furthermore, in late gestation sows fed IF had 11% greater ATTD of hemicellulose (Period×Fiber P</em>=0.035). Energy intake did not differ as dictated by design (P=0.64). Sows fed multicarbohydrases excreted less energy in their urine (519 vs. 469 GE kcal/d; Enzyme P=0.033) and in their feces (985 vs. 900 GE kcal/d; Enzyme P=0.003). This resulted in an improvement in both DE (3723 vs. 3856 kcal/kg; Enzyme P<0.01) and ME (3484 vs. 3583 kcal/kg; Enzyme P=0.041), irrespective of fiber type. In late-gestation, sows fed SF tended to have decreased GE excretion compared to IF (Period×Fiber P</em>=0.091). Sows had a 3.5% greater ME in late-gestation (3451 vs. 3572 kcal/kg; Period P<0.01).
Interactive effects of pelleting and particle size reduction of corn on ileal digestibility of starch and amino acids in corn-soybean meal diets fed to pigs
The objective was to determine the interactive effects of particle size reduction and pelleting on the apparent ileal digestibility (AID) of starch and the standardized ileal digestibility (SID) of amino acids (AA) in corn-soybean meal diets fed to pigs. Six corn-soybean meal based diets were arranged in a 3 × 2 factorial with 3 particle sizes of corn (i.e., 700, 500, or 300 μm) and 2 diet forms (i.e., meal or pelleted). An N-free diet was also used and there were, therefore, a total of 7 diets. Pigs were allowed ad libitum access to feed and water. Seven pigs (initial weight = 59.30 kg; SD = 2.77) that were equipped with a T-cannula in the distal ileum were allotted to the 7 diets using a 7 × 7 Latin square design with 7 periods. Ileal digesta were collected for 2 days after 5 days of adaptation. The statistical model included diet as fixed effect and pig and period as random effects. Contrast coefficients were used to determine effects of diet form, linear effects of particle size, and the interaction. Results indicated that the AID of starch was linearly increased (P = 0.001) with reduced particle size of corn and pelleted diets had greater (P = 0.029) AID of starch than meal diets (Table 1). The SID of Leu, Lys, Met, Phe, Thr, and Val linearly increased with reducing particle size, but the increase was greater in pelleted diets than in meal diets (interaction, P < 0.05). The SID of Arg, His, Ile, and Val also linearly increased (P < 0.05) as the particle size of corn was reduced, and the SID of all indispensable AA except Trp was greater (P < 0.05) in pelleted diets than in meal diets
Effects of nutritional strategies of growth rate manipulation during the gilt development phases on growth and reproductive performance
Our objective was to evaluate the effects of nutritional interventions for growth rate manipulation during the gilt development phases on growth and reproductive performance. A total of 810 Camborough L42 gilts from three gilt groups were received between 9 to 11 weeks of age. Gilts were individually weighed, and pens of gilts were allotted to one of two dietary treatments balanced by lot (birth week) and pen weight for a total of 24 pens/treatment. Treatments consisted of two levels of dietary nutrients: Adeq) diets based on corn, soybean meal, and wheat middlings formulated to meet or exceed the PIC standardized ileal digestible (SID) lysine (Lys) recommendations with a total dietary fiber content (TDF) of 10, 10, and 11%; and Low) slower growing diets based on corn, soybean meal, wheat middlings, and corn germ where SID Lys was reduced by 6, 11, and 11%, dietary metabolizable energy level was reduced by 2.7, 4.6, and 4.7%, and TDF content was increased to 15, 18, and 20%. Diets were fed in three phases as 60 to 120 lbs, 120 to 180 lbs, and 180 to 250 lbs of body weight. At the end of phase 3, gilts were individually weighed and the number of selected gilts per pen was recorded. After selection, gilts were heat checked with the date of heat-no-service (HNS) recorded and then sent to sow farms for breeding in the next recorded heat. Data was analyzed using generalized linear mixed models considering treatment as fixed effect, lot as random effect, and covariates were included if they were statistically significant and improved model fit. Gilts fed the Low diets had significantly lower overall average daily gain compared to gilts fed Adeq diets (P< 0.05; Table 1). This response was mainly driven by a marginal significant reduction (P< 0.10) in average daily feed intake for the gilts fed Low diets compared to Adeq, with no evidence for differences (P >0.10) in overall feed efficiency. As a result of the reduction in growth rate, gilts fed the Low diets were 4.8 kg lighter (P< 0.05) at selection compared to gilts fed Adeq diets. There was no evidence for treatment differences in selection rate, breeding rate, age at first HNS nor age at first breeding (P >0.10).
The impact high soyhull and soybean meal diet formulations on grow-finish pig performance
The objectives of this study were to two-fold in evaluating the effects of soybean meal and soyhulls inclusion level in diets fed to grow-finish pigs on growth performance. Firstly, we compared high soybean meal (minimal crystalline amino acids) vs. crystalline amino acids diet formulations. Secondly, we evaluated the addition of soyhulls and soyhulls plus xylanase to diet formulations. In a complete randomized design, a total of 463 grower pigs (BW of 28.4 ± 5.6 kg) were randomly assigned to one of four dietary treatments (n = 12 pens/treatment; 9 – 11 pigs/pen). Within each phase, dietary treatments were formulated to the same SID Lys:ME, and to meet or exceed nutrient recommendations (NRC, 2012) and were fed over three phases consisting of: 1) corn soybean-meal based diet formulated with crystalline amino acids (CON); 2) corn soybean-meal based diet formulated to meet AA requirements via soybean-meal with limited crystalline amino acids (HSBM); 3) As diet #1 with 15% soyhulls (SH); and 4) As diet #3 + commercial xylanase enzyme (SH+X). Diets were formulated with to a SID Lys:ME of 3.26, 2.46, and 1.95 in phase 1, 2, and 3, respectively. Pig BW and pen feed disappearance were recorded at phase change to calculate ADG, ADFI, and feed efficiency (G:F) over the study duration of 95 days. All data were analyzed using the PROC MIXED of SAS 9.4 with pen as the experimental unit and the model included the fixed effect of treatment with least squares means reported. There were no differences (P > 0.05) amongst treatments in phase 1 for any growth performance measures. There was an increase in ADFI of pigs fed SH and SH+X when compared to CON and HSBM (P < 0.05) in phase 2 (P2; 2.89 and 2.82 vs. 2.75 and 2.73 kg/d, respectively) and phase 3 (P3; 3.42 and 3.40 vs. 3.18 and 3.28 kg/d, respectively). However, no differences in ADG or G:F (P > 0.05) compared to CON were reported in P2 or P3. Overall, there were no differences in ADG (P > 0.05) between treatments. Pigs fed SH and SH+X had an increase ADFI compared to CON and HSBM (2.84 and 2.83 vs. 2.68 and 2.71 kg/d, respectively; P < 0.05) and a decrease in G:F when fed SH, however no differences between CON, HSBM, and SH+X (0.38 vs. 0.40, 0.40, and 0.39, respectively; P > 0.05).
Effects of increasing soybean meal in corn- or corn-DDGS-based diets on growth performance of early finishing pigs
With the recent renewable fuels initiative, demand for soybean oil is expected to reach a record high. Consequently, there will be unprecedented amounts of soybean meal (SBM) produced and available. As a result, the opportunity will arise for increased usage of SBM in swine diets at the expense of feed-grade amino acids. Therefore, this study aimed to determine the maximum amount of SBM that can be added to early finishing pigs fed corn- (Exp. 1) or corn-DDGS- (Exp. 2) based diets. Experiment 1 used 625 pigs (initially 43.2 ± 0.68 kg), 70 pens with 9 or 10 pigs per pen, and 5 added SBM levels, 19.1, 22.6, 26.3, 29.9, and 33.4%, corresponding to crude protein levels of 13.1, 14.1, 15.2, 16.2, and 17.3%, respectively, with 14 replicate pens per treatment. Experiment 2 used 1,053 pigs (initially 39.1 ± 0.78 kg), 40 pens with 26 or 27 pigs, and 4 added SBM levels, 18.2, 23.5, 28.9, and 34.3%, corresponding to crude protein levels of 18.2, 23.5, 28.9, and 34.3%, respectively, with 10 replicate pens per treatment. The diet with the highest level of SBM in each experiment contained no feed-grade amino acids. Minimum levels of Ile, Met & Cys, Thr, Trp, and Val were 58, 60, 65, 19.8, and 72% of lysine, respectively. The experimental diets were corn-SBM-based, and in Exp. 2, 20% DDGS was added to all diets. In both experiments, diets were isocaloric and formulated considering SBM NE at 100% of Corn NE. In Exp. 1, no differences were observed for BW (P = 0.42) and ADFI (P = 0.46); however, increasing SBM linearly increased ADG (P = 0.04), though the greatest change was from increasing SBM from 19.1 to 22.6%, and tended to quadratically improve feed efficiency (P = 0.09). In Exp. 2, with the inclusion of DDGS, no differences (P > 0.32) were observed for any growth performance criteria.
Effects of increasing soybean meal and valine:lysine and tryptophan:lysine ratios on finishing pig performance
A total of 621 pigs (DNA 241 × 600; initially 62.9 kg) were used in a 65-d growth trial to determine the effect of increasing soybean meal (SBM) and Val:Lys and Trp:Lys (AA) ratios on finishing pig performance. Experimental diets were corn-soybean meal-based containing 25% DGGS and fed in 3 phases. The 6 dietary treatments were arranged in a 3 × 2 factorial, with main effects of SBM level (Low, Medium, High) and AA ratios (Standard, High). Trp:Lys ratios were: Phase 1: Standard 19, High 24%, Phase 2: Standard 19, High 23%, and Phase 3: Standard 19, High 23%. Val:Lys ratios were: Phase 1: Standard 70 to 83, High 87 to 88%, Phase 2: Standard 70 to 83, High 88%, and in Phase 3: Standard 76 to 96, High 96%. The additional amino acids provided by increasing levels of SBM in diets with standard AA ratios were expected to result in a higher ADG by balancing out the high leucine from corn. Conversely, ADG was expected to stay the same as SBM increased when the Val:Lys and Trp:Lys ratios were increased. Pens of pigs were assigned to treatments in a randomized complete block design with BW as a blocking factor. There were approximately 10 pigs per pen and 12 pens per treatment. No evidence (P > 0.05) of SBM × AA ratio interactions or treatment differences was observed for any response criteria for phases 1 and 2. In phase 3, a marginally significant SBM × AA ratio interaction was observed for ADG (P = 0.084). The medium level of SBM with standard AA ratios resulted in greater ADG compared to other SBM levels (quadratic, P = 0.003), whereas no differences in ADG were observed with increasing SBM when Val:Lys and Trp:Lys ratios were increased (P = 0.501). Additionally, G:F increased at the medium level of SBM in phase 3 (quadratic, P = 0.007). In spite of the improvements observed in phase 3, there were no significant differences (P > 0.10) observed in overall ADG or ADFI. A marginally significant SBM × AA ratio interaction was observed for overall G:F (P = 0.052). Increasing SBM in diets with greater Val:Lys and Trp:Lys ratios resulted in decreased G:F (P = 0.049), whereas no difference in G:F was observed with increasing SBM in diets with standard AA ratios (P = 0.435).
Effect of low crude protein diets in young pigs when using crystalline isoleucine and leucine
An experiment was conducted to evaluate the response to low crude protein (CP) while maintaining equal standardized ileal digestible (SID) LYS and equal SID amino acid-to-LYS ratios (including MET+CYS, THR, TRP, VAL, ILE, and LEU) to test whether the addition of LEU and ILE allowed CP to drop below 19.5% without impacting performance when SID LYS was 1.35%. For the experiment, 288 pigs (~22d age, 6.29 ± 0.71, 8 reps/trt, 6 pigs/pen) were stratified by weight and randomly allotted to one of 6 treatments in a randomized complete block design. Treatments had a fixed SID LYS of 1.35% and CP ranging from 21 to 17.25% in 0.75% increments. Experimental diets were fed for 21 days, and body weights and feed disappearance were recorded. Visual fecal scores (1 = normal to 4 = watery) and visual pig appearance scores (1 = pale and hairy to 4 = normal color and well-rounded muscle) were assessed on ordered likert scales to determine the probabilities of observing a more normal stool quality and a worse visual appearance, respectively. Performance data was analyzed as a general linear model. Stool quality and visual appearance were analyzed as a generalized linear mixed model. Contrasts were used to test linear and quadratic effects of dietary CP. Results of the experiment are presented in Table 1. With constant SID Lys of 1.35%, reducing CP from 21.00 to 17.25% resulted in an increase then a decrease (linear P<0.005; quadratic, P < 0.005) in Body Weight, ADG, ADFI, and gain:feed. Average daily gain and ADFI began decreasing when CP decreased below 20.25%, whereas body weight and gain:feed began decreasing once CP was below 19.50%. There was a difference detected amongst treatments in stool quality, but this was not due to changes in crude protein levels of the diets. This suggests that protein fermentation was not directly impacting stool quality in these pigs. Decreasing dietary CP also linearly (P<0.05) and quadratically (P<0.05) affected the visual appearance of the pigs in a similar manner to performance. At the lowest levels of crude protein, pigs had a higher probability of having more coarse hair and paler skin suggesting that a nutritional stress response may be occurring.
Evaluating the influence of soybean meal and its bioactive compounds on nutrient utilization, fermentation, and gastrointestinal metabolites of nursery pigs
Recently soybean meal (SBM) has garnered more attention due to its increased feeding value during periods of stress and improved bioavailable energy. However, the influence of the innate bioactive compounds in SBM on the microbiome and fermentation products have not been fully elucidated. Thus, the experimental objective was to investigate the mechanism of action of SBM and its bioactive compounds in the gastrointestinal tract of nursery pigs. Two replications of 18 barrows (8.12 ± 0.80 kg BW; PIC800 × Camborough; N=36), were randomly assigned to a dietary treatment of either a high SBM positive control (SBMC; 28.6%), a negative control void of SBM (SP), but included soy protein isolate and concentrate to provide amino acids from soy protein the same as SBM in SBMC; SP formulated to the same contribution and composition of isoflavones as SBMC (SP+ISO; 528 mg/kg of soy-isoflavones); SP diet fortified with soybean functional lipids of lecithin and phytosterols at similar concentration in SBMC (SP+LIP; 2.85 g/kg of functional lipids); SP formulated to the same contribution and ratio of insoluble to soluble fiber as SBM in SBMC (SP+FIB; 30 g/kg of soy fiber); or SP diet fortified with lunasin peptide at 3.81 g/kg (SP+LUN). Pigs were individually housed, and limit fed 2.5 times maintenance for a metabolism study consisting of a 6-d adaptation period, followed by 72-h of urine and fecal collections. On d 12, pigs were necropsied, and ileal, cecal, and colonic digesta were collected for immediate short-chain fatty acid (SCFA) analysis. The pH of ileal and cecal digesta were also collected. Data were analyzed as a linear mixed model with treatment as a fixed effect, replicate as a random effect, and initial BW as a covariate where appropriate using PROC MIXED in SAS 9.4. The pH of both ileal (P=0.478) and cecal (P=0.874) digesta did not differ among treatments. Relative to SP, pigs fed SP+FIB and SBM had a 97.8% and 63.4% increase in acetate production, respectively (P=0.012). Similarly, pigs fed SP+FIB and SBM had increased total SCFA concentration in the ileum (P=0.016), but there was no difference among treatments for propionate or butyrate production (P>0.05). The molar proportion of butyrate was increased in the cecum in pigs fed SBMC and SP+FIB (P<0.01), which increased the total concentration (mM/g) of SCFA in the cecal digesta (P<0.05). The SP+FIB treatment had increased concentration (mM/g) and molar proportion of butyrate produced in the colon (P<0.01). While pigs fed SBMC and SP had increased molar proportion of propionate in the colon (P<0.05), total colonic SCFA concentration did not differ (P>0.05).
Effects of soybean meal and functional amino acids on growth performance of nursery pigs
An experiment was conducted to evaluate the interactive effects of soybean meal (SBM) concentration and functional amino acids (FAA) threonine, tryptophan, and methionine supplementation above the requirements on the growth performance of nursery pigs. A total of 2,592 pigs (initial BW = 6.1 kg), placed in pens of 36 mixed-sex pigs, were used in a 33-d trial. Pens of pigs were allotted to 1 of 6 dietary treatments arranged as a 2 × 3 factorial with two levels of SBM (25 or 31%) and three FAA regimens (Low, Medium, and High) with 12 replicates per treatment. Amino acid ratios were: 58.5% SID Thr:Lys, 55% SID Met+Cys:Lys, and 16.5% SID Trp:Lys for the Low treatment; 65% SID Thr:Lys, 58% SID Met+Cys:Lys, and 18.5% SID Trp:Lys for the Medium treatment; and 71% SID Thr:Lys, 66% SID Met+Cys:Lys, and 23.5% SID Trp:Lys for the High treatment. Diets were fed in two phases: phase 1 from d 0 to 19 in pellet form and phase 2 from d 19 to 33 in mash form. Pigs were weighed on d 0, 19, and 33 to calculate ADG, ADFI and G:F. Data was analyzed with the MIXED procedure in SAS. From d 0 to 19, there was no evidence (P > 0.10) for interactive effects. Pigs fed the Low FAA ratios had the poorest G:F (P = 0.004). From d 19 to 33 and overall (d 0 to 33), there was an interaction (P ≤ 0.031) for G:F, where pigs fed 25% SBM had improved G:F with Medium or High FAA whereas those fed 31% SBM had improved G:F only with High FAA. There was no evidence (P > 0.10) for differences on ADG or ADFI throughout the study.
