289 Evaluation of fecal microbiota transplantation in primiparous sows

Abstract Fifty primiparous (parity 3+) and 25 multiparous sows (DNA 241, DNA, Columbus, NE) were used to evaluate the impacts of fecal microbiota transplantation (FMT) from sows to gilts on piglet scours prevalence, mortality, and fecal microbial diversity. Fresh fecal samples were collected from the primiparous and multiparous sows on approximately d 69 and 89 of gestation. The sows selected for sampling were from the same breed week as the gilts and had a historical record of low piglet mortality with increased litter size and no medical treatment during the current gestation period. The fecal samples from the sows were pooled on an equal weight basis and used for FMT solution preparation. The gilts were randomly assigned to one of two treatments: FMT or placebo (PBO). The FMT solution was administered orally to the 25 FMT gilts on approximately d 70 through 76 and 90 through 96 of gestation, while saline was administered to the 25 PBO gilts on the same days. Fecal samples were collected from all gilts and sows at the time of farrowing and at weaning. Piglets were individually weighed at birth and 5 wk post-weaning to calculate average daily gain (ADG). Scours prevalence was recorded daily from d 0 to 6 of lactation. Fecal samples were collected from two piglets per litter at weaning and 5 wk post-weaning. Pre-wean and nursery piglet mortality and morbidity were recorded. Total DNA from fecal samples and FMT solution from each timepoint were submitted for amplicon sequencing (Illumina MiSeq, Illumina Inc., San Diego, CA) at the Iowa State University DNA Facility (Ames, IA) to evaluate differences in microbial diversity and relative abundances across treatments groups. Data were analyzed using R version 4.3.1 (R Core Team, 2023). The sow and her litter were the experimental unit and results were considered significant if P ≤ 0.05 and a tendency if 0.05 < P ≤ 0.10. The number of piglets after cross-fostering and weaned were similar across treatments (P ≥ 0.721). There was no effect of treatment group on piglet birth weight or ADG (P ≥ 0.198). Scours prevalence was less in sow litters compared with PBO litters (16.7 vs. 52.0%; P = 0.039), while FMT scours prevalence was intermediate. There was no effect of FMT on pre-wean or nursery mortality (P ≥ 0.890). In conclusion, FMT did not impact gilt litter scours prevalence, growth rate, or mortality through the nursery.