279 Maternal Programming of the Piglet Microbiome Through Supplementation with a Yeast Feed Additive

Abstract

Abstract The objective of this study was to investigate effects of live yeast supplementation of sow diets during late gestation and lactation on sow reproductive performance and piglet microbiome development. Three dietary treatments were imposed on mixed-parity sows (n = 92) from three contemporary farrowing groups during late gestation and lactation. Dietary treatments were based upon the inclusion level (%) of Actisaf Sc47 in corn/soybean meal-based diets: Control (C, 0%), Low (L, 0.1%), and High (H, 0.5%). Sows were fed their assigned gestation diet (1.8 kg ∙animal-1∙day-1/) from days 85 to 110 of gestation. On day 111 of gestation, sows were fed their assigned lactation diet (3.6 kg/head/day) until parturition. Sows were allowed ad libitum access to their assigned lactation diet beginning day one postpartum until piglets were weaned. Fecal and vaginal swabs were collected from all sows on day 85 of gestation (T1-S) and the day before parturition (T2-S). Colostrum and milk samples were collected from 30 focal sows (10/treatment group), and fecal swabs were collected from 6 piglets per focal sow (n = 180) at 24 to 36 hours after birth (T1-P) and weaning (T2-P, ~19 days old). Extracted DNA from swab samples was sequenced on the MiSeq platform targeting the V4 variable region of the 16S rRNA bacterial gene, and sequence data were analyzed using DADA2 plus various packages within the R statistical software. Generalized linear mixed models were built for sow performance data using the R lme4 package, with treatment as a fixed effect, and farrowing group, parity, and sire as random effects. Piglet performance models also included sex as a fixed effect and maternal origin instead of sire as a random effect. No significant differences were observed among dietary treatment groups for gestation or lactation length, lactation feed intake, sow body weights, sow backfat depth, litter size at birth or weaning, pre-weaning piglet mortalities, or piglet growth performance. Although alpha and beta diversity did not differ among maternal dietary treatment groups in sow colostrum, milk, fecal, or vaginal samples (T1-S or T2-S), several taxa were significantly enriched or less abundant in sow samples based upon dietary yeast inclusion levels. Diversity of piglet fecal microbiomes was not different across maternal dietary treatment groups, but community composition was different at both time-points (T1-P: PERMANOVA, R2 = 0.13, P=0.02; T2-P: PERMANOVA, R2 = 0.01, P=0.048). These results indicate that yeast supplementation in sow diets in late gestation and lactation may influence development and composition of piglet gut microbiomes in early life.