Yeast culture supplement during nursing and transport affects immunity and intestinal microbial ecology of weanling pigs.

The objectives of this study were to determine the influence of a Saccharomyces cerevisiae fermentation product on innate immunity and intestinal microbial ecology after weaning and transport stress. In a randomized complete block design, before weaning and in a split-plot analysis of a 2 × 2 factorial arrangement of yeast culture (YY) and transport (TT) after weaning, 3-d-old pigs (n = 108) were randomly assigned within litter (block) to either a control (NY, milk only) or yeast culture diet (YY; delivered in milk to provide 0.1 g of yeast culture product/kg of BW) from d 4 to 21. At weaning (d 21), randomly, one-half of the NY and YY pigs were assigned to a 6-h transport (NY-TT and YY-TT) before being moved to nursery housing, and the other one-half were moved directly to nursery housing (NY-NT and YY-NT, where NT is no transport). The yeast treatment was a 0.2% S. cerevisiae fermentation product and the control treatment was a 0.2% grain blank in feed for 2 wk. On d 1 before transport and on d 1, 4, 7, and 14 after transport, blood was collected for leukocyte assays, and mesenteric lymph node, jejunal, and ileal tissue, and jejunal, ileal, and cecal contents were collected for Toll-like receptor expression (TLR); enumeration of Escherichia coli, total coliforms, and lactobacilli; detection of Salmonella; and microbial analysis. After weaning, a yeast × transport interaction for ADG was seen (P = 0.05). Transport affected (P = 0.09) ADFI after weaning. Yeast treatment decreased hematocrit (P = 0.04). A yeast × transport interaction was found for counts of white blood cells (P = 0.01) and neutrophils (P = 0.02) and for the neutrophil-to-lymphocyte ratio (P = 0.02). Monocyte counts revealed a transport (P = 0.01) effect. Interactions of yeast × transport (P = 0.001) and yeast × transport × day (P = 0.09) for TLR2 and yeast × transport (P = 0.08) for TLR4 expression in the mesenteric lymph node were detected. Day affected lactobacilli, total coliform, and E. coli counts. More pigs were positive for Salmonella on d 7 and 14 than on d 4, and more YY-TT pigs were positive (P = 0.07) on d 4. The number of bands for microbial amplicons in the ileum was greater for pigs in the control treatment than in the yeast treatment on d 0, and this number tended to decrease (P = 0.066) between d 1 and 14 for all pigs. Similarity coefficients for jejunal contents were greater (P = 0.03) for pigs fed NY than for those fed YY, but pigs fed YY had greater similarity coefficients for ileal (P = 0.001) and cecal (P = 0.058) contents. The number of yeast × transport × day interactions demonstrates the complexity of the stress and dietary relationship.

Use of Saccharomyces cerevisiae fermentation product on growth performance and microbiota of weaned pigs during Salmonella infection.

Anaerobically fermented yeast products are a rich source of nutritional metabolites, mannanoligosaccharides, and ß-glucans that may optimize gut health and immunity, which can translate into better growth performance and a reduced risk of foodborne pathogens. The objective of this study was to quantify the effects of Saccharomyces cerevisiae fermentation product (Diamond V Original XPC) inclusion in nursery diets on pig performance and gastrointestinal microbial ecology before, during, and after an oral challenge with Salmonella. Pigs (n = 40) were weaned at 21 d of age, blocked by BW, and assigned in a 2 × 2 factorial arrangement consisting of diet (control or 0.2% XPC) and inoculation (sterile broth or Salmonella). Pigs were fed a 3-phase nursery diet (0 to 7 d, 7 to 21 d, and 21 to 35 d) with ad libitum access to water and feed. On d 14, pigs were orally inoculated with 10(9) cfu of Salmonella enterica serovar Typhimurium DT104 or sterile broth. During d 17 to 20, all pigs were treated with a 5 mg/kg of BW intramuscular injection of ceftiofur-HCl. Growth performance and alterations in the gastrointestinal microbial ecology were measured during preinoculation (PRE; 0 to 14 d), sick (SCK; 14 to 21 d), and postinoculation (POST; 21 to 35 d). Body weight and ADG were measured weekly. Rectal temperature (RT) was measured weekly during PRE and POST, and every 12 h during SCK. Diet had no effect on BW, ADG, or RT during any period (P = 0.12 to 0.95). Inclusion of XPC tended (P < 0.10) to increase Salmonella shedding in feces during SCK. Consumption of XPC altered the composition of the gastrointestinal microbial community, resulting in increased (P < 0.05) populations of Bacteroidetes and Lactobacillus after Salmonella infection. Pigs inoculated with Salmonella had decreased ADG and BW, and increased RT during SCK (P < 0.001). Furthermore, fecal Salmonella cfu (log(10)) was modestly correlated (P = 0.002) with BW (r = -0.22), ADFI (r = -0.27), ADG (r = -0.36), G:F (r = -0.18), and RT (r = 0.52) during SCK. After antibiotic administration, all Salmonella-infected pigs stopped shedding. During POST, an interaction between diet and inoculation (P = 0.009) on ADG indicated that pigs infected with Salmonella grew better when eating XPC than the control diet. The addition of XPC to the diets of weanling pigs resulted in greater compensatory BW gains after infection with Salmonella than in pigs fed conventional nursery diets. This increase in BW gain is likely associated with an increase in beneficial bacteria within the gastrointestinal tract.

Effects of dietary vitamin E and fat supplementation on pork quality.

The effects of dietary vitamin E (VE, alpha-tocopherol acetate) and fat supplementation on growth and carcass quality characteristics, oxidative stability of fresh and cooked pork patty in storage, fatty acid profiles of muscle and adipose tissue, and VE concentrations of plasma, muscle, and adipose tissue were studied. Six hundred pigs were allocated to 1 of 6 diets and fed for 63 d in a 3 x 2 factorial design. The dietary treatments included 3 fat levels (normal corn, high oil corn, high oil corn plus added beef tallow) and 2 levels of VE supplementation (40 IU/kg, normal VE supplementation; and 200 IU/kg, high VE supplementation). At 113 kg of BW, 54 pigs were slaughtered as a subsample to evaluate dietary effects on pork quality. Growth performance and meat quality characteristics did not differ (P > 0.05) among treatment groups. The high level of VE supplementation had a beneficial effect on the oxidative stability of pork as indicated by thiobarbituric acid reactive substance (TBARS) values. Lean tissue had lower (P < 0.05) TBARS in the group fed the high VE than in those fed the normal VE level. The TBARS values differed among storage periods (0 to 6 d) and also between fresh and cooked ground ham. Fat type did not significantly affect total saturated and unsaturated fatty acids proportions in the neutral and polar fraction of muscle. Adding VE acetate led to greater (P < 0.05) monounsaturated and total unsaturated fatty acid proportions in neutral lipids of muscle and adipose tissues. Increasing dietary levels of VE acetate increased the concentration of VE in plasma and muscle. These results indicate that dietary VE acetate supplementation increased (P < 0.05) lipid stability and the VE concentration of muscle.

Effects of porcine somatotropin and dietary phosphorus on growth performance and bone properties of gilts.

One hundred eight gilts (initial weight = 58.5 kg) were used to determine the effects of porcine somatotropin (pST) and dietary P on growth performance and bone mechanical properties and mineralization during the finishing phase (58 to 105 kg) and a 35-d postfinishing phase. Gilts were injected daily with placebo (control) or 4 mg of pST and fed diets containing .4, .8, or 1.2% P in a 2 x 3 factorial arrangement. From 58 to 105 kg, administration of pST increased (P < .01) ADG and G/F and decreased (P < .01) ADFI. When mean weight of the gilts in a pen reached 105 kg, half the gilts were slaughtered and first rib, femur, and third and fourth metacarpals were collected for determination of mechanical properties and bone ash. A pST x P interaction was observed (P < .05) for rib bending moment and modulus of elasticity; maximum rib bending moment was attained by control gilts at .8% P and rib modulus of elasticity values remained constant across P levels, whereas rib bending moment and modulus of elasticity increased as dietary P increased from .4 to 1.2% in pST-treated gilts. Administration of pST decreased (P < .05) stress of the rib, femur, and metacarpals compared with control gilts. Increasing dietary P resulted in a linear (P < .10) increase in bending moment, stress, and ash content for rib, femur, and metacarpal bones. The remaining 54 gilts were individually fed 1.8 kg/d of a common diet for 35 d postfinishing.(ABSTRACT TRUNCATED AT 250 WORDS)