bluuebunny/crossref_metadata_2025 huggingface dataset:
244 Effects of Leucine and Histidine to Lysine Ratios in low Crude Protein Diets on the Productive Performance of Growing Pigs
Authors: Aymerich Pau , Soldevila Carme , Bonet Jordi , Coma Jaume
Published: October 2023

This experiment aimed to determine the response of growing pigs to increasing Leu and His to Lys ratio in low crude protein (CP) diets. A total of 1,248 crossbred boars and gilts [Pietrain x (Landrace x Large White), with an initial body weight (BW) of 18.2 ± 2.40 kg (Mean±SD)], were placed in 96 pens, blocked by BW, and randomly allocated to 4 dietary treatments. Pigs were fed experimental feeds for 33 days and individually weighed at days 0, 16 and 33. Standardized ileal digestible (SID) Lys was kept constant at 1.04% in all feeds. In the low CP diets the ratio between SID Lys and CP did not exceed 7.1%. The first 2 treatments compared the effect of reducing CP (16.0 vs. 14.7%) without inclusion of L-His HCL and L-Leu. Additionally, the 2 other treatments aimed to analyze the effect of increasing SID Leu (91-98-105%) and SID His (29-30-30%) to SID Lys ratio starting in low protein feeds, by increasing crystalline Leu and His inclusion to reach the recommended ideal protein profile. In addition, all low protein feed included L-Ile. Data were analyzed in a linear mixed model with treatment and sex as fixed effects and block as random effect. Pre-planned contrasts were used to analyze the effect of reducing CP and of increasing Leu and His:Lys ratios in the low CP diets. Decreasing CP reduced ADG (0.621 vs. 0.596 kg; P = 0.008) and increased FCR (1.69 vs. 1.75; P < 0.001) but did not significantly affect ADFI (P = 0.637). However, increasing the Leu and His:Lys ratios in the low CP diets did show a reduction in FCR (1.75 vs. 1.71; P = 0.003) and an increase in ADG (0.596 vs. 0.619 kg; P = 0.015) when comparing the two extreme levels. The intermediate His and Leu levels showed only significantly greater FCR (1.73 vs. 1.71; P = 0.033) and less ADG (0.599 vs. 0.619; P = 0.033) when contrasted with the highest ratios. Those differences resulted from the second phase of the trial, from day 16 to 33, as treatment effect was not significant from day 0-16 for neither ADFI (P = 0.644), ADG (P = 0.840) or FCR (P = 0.356). No significant differences were reported between the high protein and low protein diet with the greatest Leu and His:Lys ratio (P > 0.10). In conclusion, growing pigs showed a negative response on growth and efficiency when fed low CP diets deficient in Leu and His. However, this negative effect was counterbalanced when Leu and His to Lys ratios were increased by synthetic supplementation.
151 The Effect of a Multi-Enzyme Containing Xylanase, β-Glucanase, Protease and Amylase Added to a High-Fiber Wheat-Barley-Rye-Based Diet Containing by-Products, on the Growth Performance of Weaned Pigs
Authors: Vinyeta-Punti Ester , Tactacan Glenmer , Dusel Georg , Velayudhan Deepak E
Published: October 2023

This study evaluated the effect of a multi-enzyme complex on growth performance in weaned pigs fed a wheat-barley-rye-based diet containing fiber-rich by-products and with a low level of highly digestible protein and energy ingredients. Two experimental runs were performed, each with 96 (DE x DL) × Pi pigs [24–26 days of age; 8.0 ± 0.06 kg initial body weight (BW)] assigned to two treatments in 24 pens per run (4 pigs/pen, 2 males and 2 females; 12 pens/treatment/run) in a randomized block design. Pigs were allocated to treatment on the day of weaning. Treatments comprised: 1) a nutritionally adequate wheat-barley-rye-soybean meal-based diet with added wheat bran and rapeseed meal, containing 750 FTU/kg of a commercial Buttiauxella sp. phytase (ALT), and 2) the same diet supplemented with a multi-enzyme containing 4,000 U/kg xylanase, 200 U/kg β-glucanase, 2,000 U/kg protease and 100 U/kg amylase (ALT+multi-enzymes). Diets were formulated in two phases (Pre-starter, d 0–14; starter, d 15–42) and fed ad libitum as pelleted diets for 42 days. The analyzed content of crude fiber and neutral detergent fiber in ALT diets were, respectively, 4.0% and 11.5% in pre-starter, and 4.2% and 14.8% in starter phase. Body weight was measured at the start and end of each phase, feed intake was determined weekly. Data were analyzed by one-way ANOVA using IBM SPSS 21 including run as a random effect. During pre-starter phase, average daily gain (ADG) and average daily feed intake (ADFI) were greater in pigs fed ALT+multi-enzymes vs. ALT, by 8.4% (232 vs 214 g/day) and 6.7% (300 vs. 281 g/day), respectively, although this was not statistically significant. During starter phase, pigs fed ALT+multi-enzymes exhibited increased ADG vs. ALT (+35 g/day or 5.5%; P < 0.05). For the overall period (d 0 to 42), pigs fed ALT+multi-enzyme were, on average, 1.3 kg heavier than pigs fed ALT (P < 0.05), ADG was increased by +32 g/day (4.4%; P < 0.05) and FCR tended (P = 0.07) to be reduced (1.48 vs 1.44). Total feed costs per kg BW gain, exclusive of the cost of the enzymes, tended to be reduced in ALT+multi-enzymes vs. ALT, (-0.014 USD/kg BW gain, overall; P = 0.09). These results demonstrate that the multi-enzyme supplemented on top of phytase improved growth performance. Given the established mode of action of the individual enzymes, this may have been mediated by enhanced digestibility and utilization of nutrients in the ALT diet. In conclusion, supplementing a high-fiber mixed diet containing by-products and low inclusion of highly digestible energy and protein ingredients with a multi-enzyme complex improved growth performance in weaned pigs and led to economic benefit.
213 Increasing Growth Performance by Attenuating the Transportation Stress Response in Nursery Pigs Through L-Tryptophan Supplementation
Authors: Brizgys Lauren A , Richert Jacob A , Scaff Taw , Richert Brian T , Radcliffe John Scott
Published: October 2023

Weaning and transport stress impairs intestinal function and reduces nutrient absorption leading to reduced growth performance and feed efficiency. The objective of this study was to eliminate or reduce short- and long-term, transport-induced reductions in feed efficiency and growth by providing supplemental Tryptophan (Trp) above NRC (2012) pre- and/or post-weaning. A total of 480 pigs were blocked by sex, ancestry, and body weight (BW) and used in a RCB design with a 2x2x2 factorial arrangement of pre-weaning treatment (oral gavage of Trp at 0.35, 0.45, and 0.55 g/d (increasing every 5d) pre-weaning or control), transport (transported or not at weaning), post-weaning nursery treatment (1X or 2X NRC Trp). At farrowing pigs were blocked by sex, within litter, and randomly assigned to either a pre-wean Trp or control treatment, where Trp supplementation began on d 5 post-farrowing and stopped at weaning. Post-weaning Trp supplementation included a 3 d oral gavage of Trp and 2X Trp in the diet for the entire 42 d nursery period. At weaning, all pigs were blocked by sex, weaning weight and pre-wean treatment and randomly assigned to transport and post-wean treatments. Pigs were fed four nursery phases with diets containing 1X or 2X NRC recommended concentrations of Trp. There were 10 pens/trt with 6 pigs/pen (equal barrows and gilts). Individual BW were determined every 5 d pre-weaning and every 7 d post-weaning along with pen feed intakes. Data were analyzed as a RCB using GLM procedure in SAS 9.4 with fixed effects of pre-wean dietary treatment, transport treatment, and post-wean dietary treatment, the interactions, and random effect of replicate. Pre-weaning Trp supplementation had no effect on pre-weaning growth performance. A 3-way interaction of pre-wean treatment x transportation x post-wean treatment was observed for overall nursery BW (P = 0.0148) and ADG (P = 0.0175). This interaction was the result of post-weaning Trp supplementation increasing BW and ADG in all pigs, except for transported pigs that did not receive Trp pre-weaning. While there were 2-way interactions of pre-wean treatment x post-wean treatment on ADFI at week 1 ( P= 0.0123) and week 6 (P = 0.0297) and a 3-way interaction of pre-weaning treatment x transportation x post-weaning treatment at week 2 (P = 0.0092), there were no consistent or overall effects on overall ADFI or G:F. Tryptophan improves transported pigs BW and ADG when supplemented pre- and post-weaning but does not benefit transported pigs when only supplemented post-weaning, suggesting transportation induced reductions in BW and ADG can be mitigated by supplementing Trp prior to and following transportation.
229 Effect of Two Sources of Zinc on Growth Performance and Gut Health of Piglets with a Low or Normal Birth Weight
Authors: Negrini Clara , Luise Diana , Correa Federico , Amatucci Laura , Virdis Sara , Romeo Agathe , Minetto Axel , Bosi Paolo , Trevisi Paolo , Monteiro Alessandra
Published: October 2023

Zinc (Zn) is an essential trace element for piglets. The study aimed to compare effects of two Zn sources on piglets divided into two body weight (BW) categories. At birth, piglets were weighed and divided into low BW (LBW < 1 kg) or normal BW (NBW > 1 kg). At weaning (25 days of age, d 0), 64 piglets were divided into 4 groups (8 replicates of 2 piglets/group) as follows: 1) LBW piglets fed a standard diet plus 120 ppm of Zn from ZnSO4, 2) NBW piglets fed a standard diet plus 120 ppm of Zn from ZnSO4 (CO), 3) LBW piglets fed standard diet plus 120 ppm of Zn from a potentiated Zn source (HiZox, HZ), and 4) NBW piglets fed a standard diet plus 120 ppm of Zn from a potentiated Zn source HZ. Growth performance was measured at d 0, d 9, d 14, and d 21. The fecal index was recorded daily. On d 9 and d 21, one piglet per replicate was slaughtered. Blood and gut tissue were collected to evaluate the immune and inflammatory status of the piglets. The groups were arranged using a 2 x 2 factorial design, considering the class of birth BW (LBW and NBW) and the diet (CO and HZ). For the diarrhea index, a generalized linear mixed model fitting a Poisson distribution was used. Other variables were analyzed with a linear mixed model, in which the diet, class of BW and their interaction were included as fixed factors and litter of origin was included as a random factor. Piglets from the NBW group had consistently greater BW throughout the study (P < 0.01) than LBW piglets. The treatment HZ tended to improve BW gain from d 0 to d 9 and from d 9 to d 14 (P < 0.10), and significantly influenced the G:F ratio (P < 0.05). The fecal index was decreased by HZ from d 0 to d 14, and from d 0 to d 21 (P < 0.01), particularly for LWB piglets (P-interaction < 0.01). Haptoglobin and reactive oxygen metabolites decreased from d 9 to d 21 (P < 0.01) in serum. Expression of the NFKB-2 gene was less in NBW piglets than in LBW piglets and in HZ groups. In conclusion, potentiated Zn positively influenced the growth performance of LBW and NBW piglets.
253 A Survey of Added Trace Mineral Levels in Diets Utilized in the U.S. Swine Industry
Authors: Faccin Jamil , Tokach Mike D , DeRouchey Joel M , Gebhardt Jordan T , Goodband Robert D , Woodworth Jason C
Published: October 2023

From November 2021 to February 2022, swine nutritionists representing 29 production systems and 8 nutrition supplier companies in the United States were surveyed about added trace mineral concentration in swine diets. Respondents were asked to provide trace mineral premix concentrations, amount added to the diets outside the premix, inclusion rates, and body weight ranges associated with feeding phases. Survey participants represented 4.38 million sows, or 69% of the U.S. industry. Data were compiled into 3 nursery phases (Phase 1, weaning to 7 kg; Phase 2, 7 to 11 kg; and Phase 3, 11 to 23 kg), 3 finishing phases (23 to 55 kg; 55 to 100 kg; 100 to market), gestation, and lactation. Mainly driven by pharmacological levels of zinc and copper, trace mineral levels were, on average, 9.3 times above NRC (2012) recommendations across all nursery diets (Table). Selenium and iron were the lesser extremes being close to their requirement estimates (1.0 to 1.2). In finishing diets, trace mineral levels averaged 6.4 times the 2012 NRC recommendations. Copper and manganese contributed to that number the most, with reported values more than 10 times their requirement estimates. Zinc, selenium, and iron were on the other extreme at 1.4 to 1.8 times NRC (2012) requirement estimates. Regarding sow diets, trace mineral levels were 1.9 times the 2012 NRC recommendations on average. In gestation and lactation diets, iodine was in the upper extreme, and zinc in the lower. The only difference between gestation and lactation diets was copper ratios to NRC (2012). In gestation, it was supplemented at 1.8 times, and in lactation at 0.9 times the NRC (2012) requirements estimates. In recent years, the use of alternative zinc, copper, manganese, and selenium sources has increased. Selenium had the greatest number of nutritionists using alternative sources (Se yeast or hydroxyl-selenomethionine), with 50%, 8%, and 61% for nursery grow-finishing, and sow diets, respectively. Alternative sources of zinc (chelates or complexed with amino acids) were used the least, with 25%, 8%, and 33% for nursery grow-finishing, and sow diets, respectively. Alternative copper and manganese sources had intermediate usage reported. Different herd health status, trace mineral sources, and diet formulation philosophies with a margin-of-safety mindset are reflected in the use above requirement estimates found in trace mineral concentrations observed in all production phases. Understanding current supplementation practices may help develop experiments designed to test different inclusions and provide industry trends and benchmarks of trace minerals usage.
248 Concentration of Net Energy in Corn without or with Microbial Phytase Fed to Group-Housed Pigs
Authors: Rodriguez Diego A , Lee Su A , Stein Hans H
Published: October 2023

The objective was to test the hypothesis that addition of microbial phytase to corn increases net energy (NE) by group-housed growing pigs. Three diets were formulated. The positive control (PC) diet contained corn as the sole source of energy. The PC diet contained Ca and P at the requirements for pigs (NRC, 2012). The negative control (NC) diet was similar to the PC except that this diet contained 0.08% standardized total tract digestible P and 0.12% total Ca less than the PC diet. The third diet was similar to the NC diet with the exception that this diet contained 1,000 units of phytase per kg diet. Pigs were allowed ad libitum access to feed and water. Pigs (n = 24; initial body weight = 44.99 kg; SD = 2.09) were allotted to the 3 diets using a replicated 6 × 3 incomplete Latin square design with 6 chambers (i.e., 4 pigs/chamber) and 3 periods. Oxygen consumption and CO2 and CH4 production were measured during fed and fasting states and fecal and urine samples were quantitatively collected. The statistical model included diet as the fixed effect and chamber and period as random effects. Result indicated that the apparent total tract digestibility (ATTD) of dry matter and gross energy, energy excretion in feces, urine, and heat, and NE did not differ among the 3 diets (Table 1). However, concentrations of digestible energy (DE) and metabolizable energy (ME) in diets and in corn were less (P < 0.05) in the PC diet compared with the NC diet without phytase, but no difference was observed between the PC diet and the NC diet with phytase or between the 2 NC diets. The ratio between NE and ME was not different among diets, but ME to DE was increased (P < 0.05) by supplementation of phytase to the NC diet. In conclusion, concentrations of DE and ME in corn are less if more feed phosphate and limestone are used in diets. However, concentrations of NE were not affected by supplemental phytase or Ca and P levels, even though ME to NE was increased by supplemental phytase.
251 Effects of Fat Source and Level on Growth Performance and Carcass Characteristics of Commercial Finishing Pigs
Authors: Bromm Jenna J , Tokach Mike D , Woodworth Jason C , Goodband Robert D , DeRouchey Joel M , De Jong Jon A , Berg Kiah M , Pohlen Courtney , Gebhardt Jordan T
Published: October 2023

Two experiments evaluated different fat sources and levels on growth performance and carcass characteristics in commercial finishing pigs. In Exp. 1, pigs (n = 2,160 337 × 1050, PIC; initial BW 37.3 ± 0.93 kg) were used. Pens of pigs were blocked by initial BW and randomly assigned to 1 of 4 dietary treatments. Three of the treatments included: 0, 1, and 3% choice white grease fed throughout the trial. The final treatment contained no added fat until pigs were approximately 100 kg, and then the diet containing 3% fat was fed. Experimental diets were fed over 4 phases and were corn-soybean meal-based with 40% dried distillers grains with solubles. There were 27 pigs per pen and 20 replications per treatment. Overall, increasing choice white grease decreased (linear, P = 0.006) ADFI and increased (linear, P = 0.006) G:F without influencing ADG (Table 1). Pigs fed 3% fat only during the late finishing phase (approximately 100 to 129 kg) had similar G:F compared with pigs fed 3% fat for the entire study. Increasing fat tended to increase (linear, P = 0.068) HCW. In Exp. 2, pigs (n = 2,011 PIC 1050 × DNA 600; initially 28.3 ± 0.53 kg) were used. Pens of pigs were blocked by location in the barn and randomly assigned to 1 of 5 dietary treatments arranged in a 2 × 2 + 1 factorial with main effects of fat source (choice white grease or corn oil) and level (1 or 3% of the diet) and a control diet with no added fat. There were 16 replications per treatment with 21 to 27 pigs per pen. Overall, increasing fat, regardless of source, increased (linear, P < 0.001) ADG, decreased (linear, P = 0.013) ADFI, and increased (linear, P < 0.001) G:F. Increasing fat increased (linear, P ≤ 0.016) HCW, carcass yield, and backfat depth (Table 2). There was a fat source × level interaction (P < 0.001) in belly fat iodine value (IV), where IV increased to a greater extent in pigs fed diets containing corn oil with only a small increase in IV in pigs fed diets with choice white grease. In conclusion, the results from these experiments suggest that increasing fat from 0 to 3%, regardless of source, produced variable responses in ADG but consistently improved G:F. Increasing fat increased HCW, carcass yield, and backfat depth, but feeding diets containing corn oil increased belly fat IV to a greater magnitude than choice white grease.
273 Dynamics of Bone Mineralization in Primiparous Sows as a Function of Dietary Phosphorus and Calcium During Lactation
Authors: Heurtault Julien , Létourneau-Montminy Marie-Pierre , Schlegel Patrick
Published: October 2023

In a context of maximizing the use of dietary phosphorus (P) in swine production, research should focus on understanding the mechanisms of bone P and calcium (Ca) utilization in sows. A better knowledge of P and Ca quantities that can be mobilized from bones during lactation, which would then be restored during gestation, would allow the development of new feeding strategies including this dynamic process. In turn, it can lead to a substantial decrease in dietary P supply. The role of dietary phytase supplementation also needs to be quantified in such potential strategies. In addition to the bone mineral status of sows, the consequences of these strategies on litter performance need to be documented. The objectives of the experiment were to measure the capacity of the sow to mobilize bone minerals reserves during lactation according to dietary digestible P (P dig) content and phytase addition, to restore them, during the following gestation, and to measure the effects on the growth performance of the offspring. Whole body bone mineral content (BMC) of primiparous Swiss Large White sows (n = 24) from the Agroscope sow herd was measured by dual-energy X-ray absorptiometry (DXA) on days 2, 14, 26, 66, and 106 after parturition. Four lactation diets were formulated to cover all nutritional requirements except for Ca and P dig: control without phytase (100%; 3.0 g P dig, 9.9 g Ca/kg), 75% of P dig without phytase (75%; 2.3 g P dig, 8.3 g Ca/kg), 50% of P dig without phytase (50; 1.5 g P dig, 6.0 g Ca/kg), and 50% of P dig with phytase (50+Phyt; 3.0 g P dig, 7.6 g Ca/kg). The gestation diet was formulated to cover nutritional requirements of Ca and P dig (2.6 g P dig, 8.2 g Ca/kg). Piglets were weighed at 1 and 14 days after parturition and at weaning (day 26), and the average daily gain (ADG) per piglet was calculated. During lactation, BMC of the sow (in g/kg of body weight, BW) tended to be less in treatment 50% than in treatment 100% (-12.8%, linear effect x time quadratic, P = 0.05). During gestation, BMC was similar between treatments. Therefore, sows in treatment 50% were able to recover their bone-mineralization deficit during the next gestation. The BMC (in g and in g/kg BW) was similar between treatments 100% and treatment 50+Phyt throughout the experimental period. Piglet weight at days 1, 14, and 26 and ADG (days 1 to 14, 14 to 26 and 1 to 26) were similar between dietary treatments. These results show the possibility of drastically reducing dietary P during lactation without decreasing litter performance and highlight the ability of primiparous sows to mobilize bone mineral during lactation and restore it during gestation.
271 Impact of Amount and Solubility of Dietary Fiber Fed During Late Gestation and During the Pre-Farrowing Period on Sow and Litter Performance in Lactation
Authors: Martinez Gabriela E , Wilcock Pete , van Heugten Eric , Rosero David S
Published: October 2023

This study evaluated the impact of level and solubility of total dietary fiber (TDF) on sow and litter performance when fed during late gestation and early pre-farrowing. Sows (n = 241) were assigned by body condition to a 2×2 factorial arrangement plus a control treatment (with no supplement) with the following factors: 1) Amount of a fiber supplement (0.45 or 0.90 kg), and 2) Fiber solubility (high soluble dietary fiber (SDF) of 9.63% with 25.25% insoluble dietary fiber (IDF) or high IDF of 30.73% with 4.18% SDF). Fiber supplements were formulated using sugar beet pulp and soybean hulls and were provided in addition to a common gestation (12.0% TDF) and lactation diet (11.3% TDF) from day 99 (± 1 d) of gestation until parturition. Total number of pigs born, and piglet birth weight were not impacted by treatment. Number of stillborn pigs was reduced by 0.45 kg IDF supplement (P = 0.03), but it increased ( P= 0.008) the number of low-birth weight pigs (< 1 kg) compared with control, 0.90 kg IDF, and 0.45 and 0.90 kg SDF supplement (1.31a vs. 0.50b, 0.33b, 0.47b, and 0.40b, respectively). Treatment did not affect number of pigs weaned and pig weaning weight. Number of small-weaned pigs (< 3.6 kg) was least (P < 0.001) with 0.90 kg IDF, and 0.45 kg SDF compared with control, 0.45 kg IDF and 0.90 kg SDF (0.53c and 1.00bc vs 3.31a, 3.27a, and 2.00ab, respectively). Weaning to estrus interval was reduced (P = 0.003) by 0.90 kg IDF and 0.45 and 0.90 kg SDF compared with control and 0.45 kg IDF (5.00b, 4.77b, and 5.22ab vs. 6.51a, and 6.59a days, respectively). Results suggest that composition of fiber is important, and that fiber provided as a supplement to the standard feed may be a practical strategy to improve sow performance during the late gestation and the pre-farrowing period.
277 Effect of Mode of Delivery of Fecal Microbiota Transplants on Growth Performance and Gut Microbiome in Weaning Piglets
Authors: Oladele Paul , Dong Wenxuan , Richert Brian T , Johnson Timothy A
Published: October 2023

Weaning is one of the most stressful events for piglets, due to diet change from sow milk to grain-based feed. This diet change causes turnover of the gut microbial which can allow proliferation of pathogens leading to diarrhea. Antibiotics are administered to treat or prevent post-weaning diarrhea (PWD). Increased occurrence of antimicrobial resistance has increased incentives to develop viable antibiotic alternatives. Previous studies have shown that fecal microbiota transplant (FMT) reduced diarrhea incidence and improved body weight gain in piglets. However, one barrier to FMT adoption in swine production is that FMT are generally given via oral gavage, which is difficult and labor intensive for large swine operations. For FMT to be a viable option in swine management, a simple method is needed to administer the transplant. The objective of this study was to determine the effect of three methods of FMT administration (oral, rectal and lyophilized in-feed) on growth performance, diarrhea incidence and gut microbiome. We hypothesize that FMT (in-feed and rectal) will increase colonization efficiency, improve growth performance and reduce diarrhea incidence compared with control. Weaned male piglets (n = 40) were allotted to 4 treatments at 10 piglets per treatment (no FMT - Control, Oral gavage - FMT1, rectal gavage - FMT2 and lyophilized in-feed – FMT3). Feces from 12-week-old pigs, screened for pathogens, was donor material. The study lasted nine days and FMT was for five days. Diarrhea incidences and body weight were observed for the first week. Fecal samples were collected on days 0, 2, 5 and 7. Five piglets per group were sacrificed on day 4 and the remaining on day 8. Cecal and colon contents were collected from the sacrificed piglets. DNA was extracted from fecal and digesta samples and 16S rRNA gene libraries (V4 region) were prepared for bacterial community analysis. Data were analyzed with one-way ANOVA in R. All FMT groups had significantly greater body weight on day 3 (P < 0.05) and average daily gain between day 0 – 3 (P < 0.05) compared with control but there was no difference between FMT groups. There was no effect of FMT on average daily feed intake and diarrhea incidence. Only FMT3 had greater alpha diversity (Observed features and Faith’s phylogenetic diversity) on day 5 (P < 0.05) compared with control, but there was no difference in beta diversity between FMT groups. There was decreased abundance of 27 ASVs (amplicon sequence variant) and increased abundance of 30 ASVs in increased in FMT3 compared with control on day 5. In conclusion, the three FMT groups has similar colonization pattern but there was no difference in diarrhea incidence. FMT3 (lyophilized in-feed) altered overall community structure of piglets and modulated individual taxa.
275 Awardee Talk: Gnotobiotic Porcine Models to Better Understand Gut Microbiome-Host Interactions in Human and Porcine Hosts
Authors: Aluthge Nirosh D
Published: October 2023

Better understanding the interactions between the gut microbiome and its host is at the forefront of research conducted in areas related to human health as well as livestock production. The complexity of the gut microbiome as well as the numerous environmental and host factors that influence the structure and function of the microbial community complicates the study of host-gut microbiome interactions under natural conditions. To this end, germ-free animal models which have been transplanted with target microbiomes and raised under controlled experimental conditions provide a unique opportunity to mitigate some of the inherent difficulties related to studying host-microbiome interactions in conventional animals as well as in humans. Due to its high degree of similarity to humans at the anatomical, biochemical, and immunological levels and its importance in the livestock industry, the domestic pig (Sus scrofa domesticus) is an excellent animal model which has a unique ‘dual-purpose’ potential for use in both human health and livestock production research. Using high-throughput DNA sequencing technologies, we have demonstrated some of the advantages of using human microbiota-associated (HMA) porcine models compared with commonly used HMA mouse models to study the human gut microbiome. Specifically, we identified that a significantly greater percentage of taxa from child, adult, and senior donors were able to colonize (69% to 85% in pigs versus 41% to 49% in mice) and persist (28% to 57% in piglets versus 21% to 28% in mice) in the HMA piglets compared with the HMA mice, and that this was primarily driven by a greater colonization success of Firmicutes members in the pigs compared with the mice. In addition, we have characterized human infant microbiota-associated porcine models at both the taxonomic and functional levels to better understand the HMA piglet as a model for infant microbiome investigations. We have also utilized the porcine microbiota-associated (PMA) pig model to understand the establishment and development of the porcine gut microbiome. This model has great potential to dissect the mechanistic relationship between the host and its microbiome in pigs. Additionally, this model can be used to understand how prebiotics and direct-fed microbials might interact with the gut microbiome and influence porcine health and well-being. Despite some of the challenges to the widespread use of gnotobiotic porcine models, such as high overhead costs and labor involved in animal care, the porcine model holds a lot of promise to help better understand host-gut microbiome interactions.
286 The Effect of Dietary Copper Levels and Source on the Performance and Profitability of Finishing Pigs
Authors: Bradley Casey L , Mshengu S'phamandla B , Raath Jaco J , Nolasco Liliana , Van Deventer Myles , Steyn Willem J , Pennicott Chantel
Published: October 2023

The micronutrient copper (Cu) is known to improve performance variables and the overall health of livestock animals. Different responses have been reported based on the molecular form of Cu and the inclusion level supplemented to growing pigs. The objective of this experiment was to evaluate four inclusion levels (25 ppm, 75 ppm, 125 ppm, 175 ppm) of CuSO4 and two Cu sources tribasic Cu chloride and organic Cu, in performance variables and economics of production of pigs during the grower-finisher phases. This trial was conducted at the Baynesfield Swine Research Unit at Baynsefield Estate in KwaZulu Natal, South Africa, following local farm protocols. A total of 528 animals (70 d of age; Initial BW of 33.1 ± 0.31 kg; TN 70 Topig Genetics) were randomly allotted to 48 mixed sex pens, with 11 pigs/pen. The treatments were as follow: TRT1 25 ppm CuSO4, TRT2 75 ppm CuSO4, TRT3 125 ppm CuSO4, TRT4 175 CuSO4, TRT5 hydroxy Cu, and TRT6 organic Cu. Each treatment had 8 repetitions with an equal number of boars and gilts (44). A four-phase corn and soy-based diet were formulated on the same specs having the premixes altered to accommodate the four Cu levels and/or Cu sources. Experimental animals had ad libitum access to feed and water. Feed intake and body weight were measured at every phase change. Additionally, the carcass variables (lean meat %, grading, cold carcass weight, and dressing%) were measured at slaughter. Feed cost, carcass value, MOFC, and cost per gain were calculated to determine economic value for each treatment. Statistical analysis was conducted in SAS (2021) utilizing the Proc GLM model for the average effects within each period, and if significant (P < 0.05) the Fisher’s test was used for LSMeans. There were no significant differences between the dietary treatments for BW, ADFI, ADG, FCR, or yield (Table 1). However, cost over feed was greater for the TRT6 fed pigs compared with either the TRT2 or TRT3 treatments but similar to the other treatments (P < 0.05). But when considering margin over feed, there were no significant differences amongst the treatments. In conclusion, this trial did not demonstrate an economic advantage of feeding copper greater than 75 ppm or utilizing alternative forms of copper.
285 Effects of Dietary Lysozyme Supplementation on Nitrogen Balance, Microbiota Diversity and Growth Performance of Growing Pigs
Authors: Schroeder Bruna , Pomar Candido , Andretta Ines , Petri Renée , Ronholm Jennifer , Escobar Jeffery , Ricci Sara , Remus Aline
Published: October 2023

Lysozyme is an enzyme with antimicrobial properties that might improve gut health. This study aimed to evaluate the effect of lysozyme supplementation on growth performance, nitrogen (N) balance, and microbiota diversity of pigs and to determine the optimal inclusion level of this enzyme. Barrows [n = 72; 40.6 kg ± 2.6 body weight (BW); Yorkshire x Landrace] were used for this experiment. Pigs were distributed in a completely randomized design with 12 replicates within six dietary treatments (0, 16, 32, 48, 64, and 80 mg of lysozyme/kg of diet). Pigs were housed in the same pen, and individual transponders allowed feeders to identify the pigs, record their feed intake, and provide feed according to the individual assigned treatment. Animal growth performance was evaluated through average daily feed intake (ADFI, kg/d), average daily gain (ADG, kg/d), and gain-to-feed ratio (G:F, kg/kg) over 21 days. The N balance was estimated by dual-energy X-ray on days 1 and 21. The digesta in the jejunum segment was collected to study microbiota alpha and beta diversity. The linear-plateau and quadratic-plateau models were used to determine the optimal dietary lysozyme inclusion level as a function of ADG. The data were analyzed as completely randomized, the main fixed effect was lysozyme dose, and the scanning day was considered a random effect. The ADFI decreased linearly (P ≤ 0.01), while ADG, G: F and N utilization efficiency increased linearly (P ≤ 0.01) with the inclusion of lysozyme. Based on the non-linear models estimates, the minimal dietary lysozyme concentration maximizing ADG was 40 mg/kg, and no ADG response was observed above 50 mg/kg of supplementation. Shannon and inverse Simpson indices showed significant differences between cecum and jejunum (P ≤ 0.05) and due to the lysozyme, whereas treatments did not impact Chao1, ACE indexes and observed features, suggesting a treatment effect on species evenness but not on species richness. The treatments did not affect any of the beta diversity matrices analyzed. Based on these results, lysozyme supplementation up to 50 mg/kg may affect the species evenness in jejunum digesta while improving N utilization efficiency and ADG.
302 Interactive Effects of Pelleting and Particle Size Reduction of Corn on net Energy and Digestibility of Nutrients in Corn-Soybean Meal Diets Fed to Group-Housed Pigs
Authors: Lee Su A , Rodriguez Diego A , Stein Hans H
Published: October 2023

The objective was to determine the interactive effects of reducing particle size of corn and pelleting on the apparent total tract digestibility (ATTD) of gross energy (GE), fiber, fat, calcium, and phosphorus, N balance, and net energy (NE) 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). Pigs were allowed ad libitum access to feed and water. Pigs (n = 24; initial body weight = 29.52 kg; SD = 1.40) were housed in indirect calorimetry chambers and allotted to the 6 diets using a 6 × 6 Latin square design with 6 chambers (i.e., 4 pigs/chamber) and six 15-day periods. Fecal and urine samples were quantitatively collected during a 6-day period following 7 days of adaptation and O2 consumption and CO2 and CH4 productions were measured during fed and fasting states. The statistical model included diet as fixed effect and chamber 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 reducing the particle size of corn increased the ATTD of GE and of acid hydrolyzed ether extract (AEE) in meal diets, but not in pelleted diets (interaction, P < 0.001; Table 1). The ATTD of Ca was reduced in diets containing 500 μm corn by pelleting to a greater extent than in diets containing 300 or 700 μm corn by pelleting (interaction, P = 0.004), but regardless of corn particle size, the ATTD of P was less (P = 0.037) in pelleted diets compared with meal diets. The ATTD of N increased to a greater extent in meal diets than in pelleted diets as particle size was reduced (interaction, P = 0.021). The NE of diets increased as particle size of corn was reduced from 500 to 300 μm in meal diets and from 700 to 500 μm in pelleted diets (interaction, P = 0.004). The ATTD of GE, N, and AEE, and the NE of diet were greater (P < 0.05) in pelleted than in meal diets, but the ATTD of Ca and P was greater (P < 0.05) in meal diets than in pelleted diets. The ATTD of total dietary fiber and N retention were not affected by diet form or particle size of corn. In conclusion, reducing the particle size of corn from 700 to 300 μm increases the NE of a corn-soybean meal diet due to increased ATTD of GE, N, and AEE, but the increment in NE or the ATTD of nutrients depends on diet forms.
301 Effects of Different Sources and Particle Sizes of Field Peas on Ileal Digestibility of Amino Acids and Starch by Growing Pigs
Authors: Ibagon Jimena A , Lee Su A , Nyachoti Charles Martin , Stein Hans H
Published: October 2023

The objective was to test the hypothesis that particle size and origin influence the apparent ileal digestibility (AID) of starch and the standardized ileal digestibility (SID) of amino acids (AA) in field peas. Three sources of field peas were procured. One source was from the U.S. and 2 sources were from Canada. The U.S. source and 1 of the sources from Canada (i.e., Canada 1) were each divided into 2 batches and ground at 200 or 400 µm, whereas the other source from Canada (i.e., Canada 2) was only ground at 200 µm. Each source of field peas was included in one diet as the only source of AA. An N-free diet was used to determine the basal endogenous losses of crude protein (CP) and AA. Barrows (n = 6; initial body weight: 50.5 kg; SD = 3.7) that had a T-cannula installed in the distal ileum were randomly allotted to a 6 × 6 Latin square design with 6 diets and six 7-d periods. Ileal digesta from pigs were collected for 2 days after 5 days of adaptation. The statistical model included source as the fixed effect and animal and period as the random effects. Contrast statements were used to analyze effects of particle size, origin, and the interaction between particle size and origin. Results indicated that the AID of starch was increased by reducing the particle size of the U.S. source, but that was not the case for the Canada 1 source (interaction; P < 0.001; Table 1). No interactions were observed for the SID of CP or AA. The SID of CP and AA was not affected by particle size of field peas. The SID of CP and Trp was greater (P < 0.05) and the SID of His, Ile, and Thr tended to be greater in the Canada 2 source (P < 0.10) than in the U.S. source. In conclusion, a few differences in the SID of AA in field peas produced in the U.S. or Canada were observed, but there was no effect on SID of AA of reducing the particle size of field peas from 400 to 200 µm. However, the effect of particle size on the AID of starch was greater in field peas from the U.S. compared with field peas from Canada.
73 Effects of Fatty Acids Sources and Lysophospholipids on Nutrient Digestibility in Lactating Cows
Authors: Porter Noah , Park Kiyeon , Clark Kirsten , Rebelo Lucas , Kwon In Hyuk , Lee Chanhee
Published: October 2023

Fatty acids (FA) are a common supplement for lactating cows to increase energy supply, potentially improving feed efficiency and milk and milk fat yields. However, different FA can cause varying responses probably because of different FA digestibility and interactions with other nutrients (e.g., fibers). Lysophospholipids (LPL) are natural emulsifiers and LPL as a feed additive have shown increases in FA digestibility and nutrient absorption in non-ruminant animals. This study aimed to investigate the effects of FA sources with LPL supplementation on nutrient digestibility in lactating cows. Mid-lactation cows (n = 48) were allocated into 12 blocks, and cows in each block were randomly assigned to the following dietary treatments:1) a diet with a FA supplement [1.8% of dietary dry matter (DM)] mainly containing palmitic acid (PA); 2) the PA diet with LPL (0.003% of dietary DM); 3) a diet with a FA supplement (1.8% of dietary DM) mainly containing stearic acid (SA); and 4) the SA diet with LPL (0.003% of DM). The experiment was conducted for 6 weeks, and spot samples of feces and urine were collected over 3 days (every 3 hours within a 24-hour cycle) during the last week of the experiment to determine nutrient digestibility and utilization. Data were analyzed using the mixed model with FA source, LPL, and their interaction as fixed effects and block as a random effect. The digestibility of DM, organic matter, and crude protein were not affected by the FA source and no interaction between FA and LPL was observed. However, PA had greater neutral detergent fiber (NDF) digestibility (41.4 vs. 38.8%; P = 0.04) than SA with no interaction between the FA source and LPL. In addition, as expected, PA decreased (P < 0.01) the digestibility of 16-carbon FA compared with SA due to the greater C16:0 supply, and SA decreased (P < 0.01) that of 18-carbon FA compared with PA due to the greater C18:0 supply. Supplementation of LPL did not affect digestibility of DM, OM, CP, and NDF, but increased total FA digestibility (64.7 vs. 60.5%; P = 0.02) compared with no LPL. In addition, LPL increased 18-carbon FA digestibility (68.2 vs. 74.1%; P < 0.01) compared with no LPL. An interaction between LPL and FA was observed for 16-carbon digestibility because LPL increased 16-carbon digestibility with SA but not with PA. In conclusion, PA supplementation improved fiber digestibility compared with SA, which could be a factor for increased productivity (e.g., milk fat). Supplementation of LPL was effective in increasing FA digestibility and may have potential to increase dietary energy supply or provide a similar energy supply with less dietary fat content in practice. However, more studies are needed to understand different interactions of LPL with FA sources.
157 Daily Versus Three Times a Week Ddgs Supplementation on Grazing Calves
Authors: Vanderhoff Sydney T , Sjostrand Rebecca L , MacDonald Jim C , Drewnoski Mary E , Norman Mitchell M
Published: October 2023

Supplemental feed may be provided to cattle in grazing systems to increase ADG, but can be labor intensive. This study evaluated the performance of steers grazing smooth bromegrass pastures supplemented dried distillers grains plus solubles (DDGS) either daily or three times per week. Crossbred steers (n = 144, initial BW 317 ± 1.25 kg) were used in a randomized complete block design with 3 treatments allocated randomly to 24 paddocks in one of 6 blocks. Treatments consisted of: 1) steers supplemented daily with 0.8% of BW (DM-basis) of DDGS, 2) steers supplemented three times a week with 1.86% of BW (DM-basis) of DDGS, and 3) steers that received no supplementation (control). All steers were implanted with 40 mg trenbolone acetate and 8 mg estradiol (Rev-G; Merck Animal Health, De Soto, KS) implants. Paddocks were divided equally into three strips and rotationally grazed. Put-and-take steers were utilized to match stocking rate with forage growth. Each treatment group rotated through three 0.81-hectare strips per pasture. Pre-graze and post-graze biomass was measured at ground level from each paddock at each rotation. Pre-graze biomass samples were used to determine forage availability. Grazing was initiated in early May with cattle removed from pastures in August, for a total of 97 grazing days. Data were analyzed with MIXED procedure of SAS with paddock as experimental unit and treatment and block as fixed effects. Treatment means of ADG and ending BW differed (P < 0.01) among treatments. The control calves gained 0.85 kg/d. The supplemented treatments significantly increased (P < 0.01) ADG compared with the control, with daily supplementation gaining 1.25 kg/d and 3x gaining 1.11 kg/d. The ADG was decreased (P < 0.01) with 3x a week compared with daily supplementation. The differences in ADG resulted in similar differences in final live BW. The control had a finial live BW of 398 kg and final live BW of both supplemented treatments was significantly increased (P < 0.01) when compared with the control treatment. Final live BW of 3x supplemented steers (423 kg) was decreased (P < 0.01) when compared with daily supplemented steers (436 kg). For steers grazing smooth bromegrass pastures, daily supplementation of DDGS resulted in greater gains and therefore greater final BW when compared with three times a week supplementation and the non-supplemented control.
166 Influence of Source of Metabolizable Protein and Implant Status on Feedlot Performance and Feeding Behavior in Yearling Steers
Authors: Petzel Emily A , Acharya Subash , Shiba Setsabile , Bailey Eric , Brake Derek W
Published: October 2023

Crossbred steers (n = 60; beginning BW 454 ± 24 kg) were used in a split-plot design with a 2 x 3 factorial arrangement of treatments to determine effects of source of metabolizable AA and implant status on animal performance and feeding behavior. Calves were blocked by initial BW and assigned to 1 of 5 BW blocks. Pen (n = 2 pens, 6 steer/pen) within each BW block were fed diets formulated to meet the RDP requirement of cattle and provide 150% and 152% the metabolizable Lys and Met requirement (RP-AA), or a diet designed to meet RDP and closely match the predicted metabolizable Lys and Met requirement (RDP-ONLY; metabolizable Lys = 99.3% of required; metabolizable Met = 119% of required, NASEM, 2016). Subsequently, within pen two calves were randomly assigned to 1 of 3 implant strategies: no implant, moderate (100 mg trenbolone acetate and 14 mg estradiol; Synovex Choice) or potent (200 mg trenbolone acetate and 28 mg estradiol; Synovex Plus). Cattle were fed for 125 days and feed intake and feeding behavior was determined using a semi-autonomous feed monitoring system (GrowSafe System Ltd). Data were analyzed using the MIXED procedure of SAS. There was a tendency for an interaction of source of metabolizable AA and implant status on dry matter intake; calves with a moderate implant consumed less feed when fed RP-AA while calves with a potent implant consumed greater amounts. Dry matter intake was not affected by metabolizable AA supply (P = 0.87) or implant status (P = 0.43). There was an interaction of source of metabolizable AA and implant status on ADG; implanted calves gained similar amount regardless of source of metabolizable AA, but non-implanted calves fed RP-AA gained 25% less compared with RDP-ONLY diet. Moderate and potent implants had greater ADG (P < 0.01) than non-implanted cattle. Overall, ADG was not affected by source of metabolizable AA (P=0.95). Feeding behavior was largely unaffected by source of metabolizable AA or implant status. Feed intake per meal, number of meals per day, meal duration and visit duration were not influenced by source of metabolizable AA or implant status (P ≥ 0.16). Number of visits per meal tended (P = 0.07) to be greater for RP-AA while feeding rate tended (P = 0.09) to be less. There was a significant interaction of source of metabolizable AA and implant status on feeding rate (P < 0.01) as non-implanted and potently implanted calves ate feed at a lesser rate when fed RP-AA but moderately implanted calves fed RP-AA ate feed at a greater rate compared with RDP-ONLY. These data demonstrate that metabolizable AA requirements of growing cattle are dynamically related to implant status in cattle, but that implant status does not largely influence feeding behavior.