Symposium on Gut Health in Production of Food Animals 2021

Chairperson: Cristiano Bortoluzzi / Speaker: Maria Mendoza, Evonik Corporation

The functional amino acids (FAA) Met, Thr, and Trp play an important role supporting the immune system and gut health. Two studies were designed to evaluate the supplementation of FAA above requirements during a Salmonella Typhimurium (ST) challenge. Experiment 1 was conducted for 14 d in a 2 × 2 × 2 factorial arrangement, consisting of 2 CP levels (16% or 20%), 2 FAA levels (Met, Thr, and Trp at 100% [FAA−] or 120% of requirements [FAA+]), and 2 challenge conditions (saline [CT] or ST inoculation). Pigs (initial BW = 13.9 kg; 8 pigs/treatment [Trt]) received the diets from d 0 to 14, and on d 7 pigs were inoculated. Pigs inoculated with ST had higher rectal temperature, serum haptoglobin, and activity of antioxidant systems, softer feces, and lower growth compared with CT pigs. Pigs challenged with ST and fed FAA+ diets had a less severe acute inflammatory response and greater growth compared with FAA− counterparts. Pigs fed 16% CP diets had lower cecal ST score compared with pigs fed 20% CP diets. Protein level did not affect growth and immune status. Experiment 2 was conducted for 21 d to evaluate whether providing an adaptation period of FAA+ is beneficial during health challenges. All pigs (initial BW = 11 kg, 8 pigs/trt) were inoculated with ST on d 14. Pigs were fed FAA− or FAA+ diets at different periods. The 4 treatments included (1) FAA−, only FAA−, (2) FAA+15, pigs received FAA− and from d 15 FAA+, (3) FAA+8, pigs received FAA− and from d 8 FAA+, and (4) FAA+, only FAA+. As in Exp. 1, pigs experienced an acute inflammatory response due to ST regardless of the treatments. Pigs fed FAA+ diets had lower levels of serum haptoglobin, activity of antioxidant systems, cecal ST score, and greater growth compared with FAA−. Pigs fed FAA+15 and FAA+8 had intermediate activity of antioxidant systems and growth compared with FAA− and FAA+. Both experiments demonstrated that pigs fed FAA+ are better equipped to counteract an ST infection while maintaining optimum growth, and the benefits are greater when pigs are fed FAA+ diets for a longer period.

Key Words: functional amino acids, pig, Salmonella.

Authors: L. A. Rodrigues 1,2, M. O. Wellington 2, J. C. González-Vega 3, J. K. Htoo 3, A. Menconi 4, S. M. Mendoza *4 , A. G. Van Kessel 2, and D. A. Columbus 1,2 / 1 Prairie Swine Centre Inc., Saskatoon, Saskatchewan, Canada, 2 Department of Animal and Poultry Science, University of Saskatchewan, Saskatoon, Saskatchewan, Canada, 3 Evonik Operations GmbH, Hanau-Wolfgang, German, 4 Evonik Corporation, Kennesaw, GA, USA.

Yang Lin, University of Georgia

A total of 252 Cobb 500 male broiler chicks were used in a 21-d experiment to study the possibility of xylo-oligosaccharides (XOS) helping to recover gut impairment in Eimeria-challenged broilers by regulating the expression of nutrient transporters and tight junctions, and cecal short-chain fatty acids (SCFA), which is an indicator of bacterial status. Birds were allocated to 6 treatments in a 3 × 2 factorial arrangement (3 corn-soybean diets with 0, 0.5, 1 g/kg XOS × with or without Eimeria challenge). Each treatment had 6 replicates with 7 birds per replicate. Challenged groups were inoculated with a solution containing E. maxima, E. tenella, and E. acervulina oocysts on d 15. On d 21, jejunal tissue was collected for gene expression analysis and cecal content was collected for SCFA analysis. The Eimeria × XOS interaction for tight junction claudin 1 showed that both 0.5 and 1 g/kg XOS alleviated (P < 0.05) Eimeria-induced claudin 1 upregulation. The Eimeria × XOS interaction for sugar transporters showed the extent of Eimeria-induced GLUT2 and GLUT5 downregulation was smallest in the 0.5 g/kg XOS supplemental treatment. In addition, Eimeria upregulated (P < 0.01) tight junction JAM2 and glucose transporter GLUT1 but downregulated (P < 0.01) the peptide transporter PepT1, amino acid transporters rBAT, CAT2, y+LAT2, and zinc transporter ZnT1. Eimeria decreased (P < 0.05) cecal saccharolytic SCFA acetate, butyrate and total SCFA, but increased (P < 0.05) cecal branched-chain fatty acids isobutyrate and isovalerate. The supplementation of XOS tended to decrease the concentration of isobutyrate (P = 0.080) and isovalerate (P= 0.062). In conclusion, Eimeria challenge triggered changes in expression of tight junction and nutrient transporter genes. Supplemental XOS helped reverse the gene expression changes in tight junction claudin 1 and glucose transporter GLUT2 and GLUT5, and showed the potential of alleviating the Eimeria[1]induced unfavorable cecal fermentation pattern.

Key Words: xylo-oligosaccharides, Eimeria, tight junction, nutrient transporter, short-chain fatty acids (SCFA).

Authors: Y. Lin* and O. Olukosi, University of Georgia, Athens, GA, USA.

Gilson Gomes, AB Vista

Salmonella control in poultry flocks and its public health impact is crucial. The objective of this study was to evaluate the effects of a stimbiotic (Signis, AB Vista, Marlborough, UK). A total of 900 day-old chicks were randomly allocated to 60 pens. The trial design was a complete 2 × 2 × 2 factorial with 2 based diets, a standard commercial diet with (PC) or without a multi NSP enzyme and a prebiotic (NC), with or without the stimbiotic at 100 g/ton of feed fed to males or females. Body weight (BW), feed intake (FI), and livability were recorded per pen. The feed conversion ratio was corrected for mortality (mFCR) and BW (mbwcFCR). Four birds per pen were randomly selected and cecal content collected and pooled for the enumeration of Salmonella by most probable number (MPN) test culture. Performance data were submitted to a 2-way ANOVA, means were separated using a Student’s test with significance accepted when P ≤ 0.05. Livability and Salmonella MPN were analyzed by Chi-squared where means were separated using Wilcoxon test. Contingency analysis was performed on the presence/absence % of Salmonella. No effect was observed on livability. For almost all criteria tested there was an interaction between the stimbiotic and sex, which means in this study a greater effect in males. An interaction between diet and stimbiotic was noticed on Salmonella count (P < 0.05), which was reduced for birds fed the stimbiotic, but this effect was more pronounced when supplemented on top of the NC. As a result, the proportion of Salmonella positivity was reduced from 26.7% to 13.3% when the stimbiotic was supplemented regardless of the diet. There was an interaction between the diet and the stimbiotic on mFCR (P < 0.05), mbwcFCR (P < 0.05), and FI (P < 0.05), with a larger effect noticed when supplemented to NC. In conclusion, birds fed the stimbiotic showed better performance while reducing Salmonella positivity, irrespective of sex and diet. Thus, the stimbiotic can serve as a nutritional strategy to improve performance and gut resilience mitigating Salmonella proliferation in the intestinal tract.

Key Words: stimbiotic, Salmonella, gut resilience, performance.

Authors: X. Rousseau*, N. Amornthewaphat, G. A. Gomes, and T. T. dos Santos, AB Vista, Marlborough, United Kingdom.

S. F. Leiva, Auburn University

Previous studies demonstrate that maternal supplementation of the circulating metabolite of vitamin D3 (D3), 25-hydroxycholecalciferol (25OHD3), enhances the immunocompetence of broiler chick offspring. To assess the effect of combining maternal (MD) and post-hatch (PD) dietary 25OHD3 inclusion on duodenal (DUO) crypt cell proliferation and local innate immunity of young broiler chickens, a randomized complete block design experiment with a 2 × 2 factorial treatment structure was conducted. All diets were formulated to provide 5,000 IU of vitamin D. From 25 to 41 wk-of-age, broiler breeder hens were fed 1 of 2 MD: 5,000 IU D3 per kg of feed (MCTL) or 2,240 IU of D3 + 2,760 IU of 25OHD3 per kg of feed (M25OHD3). Male broiler offspring (n = 480) hatched from eggs collected from 41-wk-old hens were fed 1 of 2 starter PD: 5,000 IU D3 per kg of feed (PCTL) or 2,240 IU D3 + 2,760 IU 25OHD3 (P25OHD3). DUO samples (n = 12 birds per treatment per day) were collected on d 3, 6, 9, 12, 15, 18, and 21 for cryohistological and immunofluorescence analysis to facilitate the enumeration of total macrophages, CD80+ macrophages (pro-inflammatory macrophages), and mitotically active cells (BrdU+) to calculate the proportion of proliferating cells per duodenal crypt (PPC). Broilers from the M25OHD3:PCTL group had higher PPC than MCTL:PCTL on d 3 (P = 0.002). On d 9, MCTL:P25OHD3 broilers had more proliferating, proinflammatory macrophages compared with those from the M25OHD3:P25OHD3 treatment (32 vs. 17 cells per mm2; P = 0.023). M25OHD3:PCTL broilers had more total proliferating macrophages than M25OHD3:P25OHD3 birds (89 vs. 56 cells per mm2; P = 0.033). At d 21, a MD × PD interaction was observed, where birds from the M25OHD3:P25OHD3 treatment had more proliferating macrophages than M25OHD3:PCTL broilers (P = 0.029). In conclusion, these results indicate that combined MD and PD 25OHD3 supplementation may alter early post-hatch duodenal development and local intestinal innate immunity parameters.

Key Words: 25-hydroxycholecalciferol, vitamin D, intestinal de[1]velopment, intestinal macrophages.

Authors: S. F. Leiva *1, L. P. Avila 1, G. A. Abascal-Ponciano 1, J. J. Flees 1, K. M. Sweeney 2, J. L. Wilson 2, J. D. Starkey 1, and C. W. Starkey 1 / 1 Department of Poultry Science, Auburn University, Auburn, AL, USA, 2 Department of Poultry Science, University of Georgia, Athens, GA, USA.

K. D. Teague, University of Arkansas

The objective of this experiment was to investigate the effects of the soy galactooligosaccharides (GOS) raffinose and stachyose on performance and gastrointestinal health in young broilers. Birds were fed a GOS-devoid diet based on soy protein isolate (SPI) or the SPI diet with 0.9, 1.8, 2.7, or 3.6% GOS. Stachyose and raffinose were maintained at a ratio of 4:1, similar to what is found in soybean meal, and were added at the expense of corn starch. These 5 treatments were administered to 10 replicate battery cages of 8 birds (0.04 m²/bird). Birds had ad libitum access to feed and water and BW and feed consumption were recorded on 0, 7, 14, and 21 d post-hatch for calculation of feed intake (FI), body weight gain (BWG), and feed conversion ratio (FCR). On 14 and 21 d, whole blood was collected for complete blood counts. Before blood collection on 21 d, birds were orally gavaged with fluorescein isothiocyanate-dextran (FITC-d), and serum samples were analyzed for FITC-d as a marker of gut leakage. Excreta were collected on d 14 for moisture analysis. Crop presumptive lactic acid bacteria (LAB) counts and crop and ceca pH were recorded at d 21. From 0 to 21 d, FI increased linearly (P < 0.01) as dietary GOS increased, whereas BWG increased (P < 0.05) quadratically. Feed conversion ratio increased (P < 0.01) linearly, with a 3-point increase from birds fed SPI to 3.6% GOS. On d 14, there was a linear increase (P < 0.01) in excreta moisture as dietary GOS increased. There was a quadratic increase (P < 0.05) in crop LAB recovery and a tendency for lower (P = 0.08) crop pH as GOS increased, whereas ceca pH decreased (P < 0.01) linearly. At both d 14 and 21, linear increases (P < 0.05) in whole blood heterophil to lymphocyte ratios were observed as dietary GOS increased. Serum concentrations of FITC-d increased quadratically (P < 0.01) as dietary GOS increased, with the greatest numerical FITC-d observed at 1.8%. No histopathological lesions were observed in duodenum or ileum of all groups. Results from this trial indicate that soy GOS have dose-dependent effects on broiler health and feed efficiency from 0 to 21 d.

Key Words: soybean meal, oligosaccharide, raffinose, stachyose.

Authors: K. D. Teague *1, G. Tellez-Isaias 1, V. Petrone-Garcia 2, C.N. Vuong 1, A. Blanch 3, S. H. Rasmussen 3, K. Brown 3, and S. J. Rochell 1 / 1 University of Arkansas, Fayetteville, AR, USA, 2 National Autonomous University of Mexico, Mexico City, Mexico, 3 Hamlet Protein, Horsens, Denmark.