Effects of gestational antibiotics on pig gut microbiota and growth

Maternal microbiota modulates the development of the microbiota in the o?spring. E?ects of gestational antibiotics are not well understood, as most studies have focused on the perinatal period. We treated sows with penicillin, tetracycline, or saline on days 78-80 of the 114-119-day gestation. Microbiotas were analyzed by 16S rRNA gene amplicon sequencing in sow feces and vagina at days 77 and 113, in colostrum within six hours after parturition, and in piglet feces at three days, three weeks, and 10 weeks of age. Antibiotic treatment had no significant effects on the sow microbiota on day 113. However, the piglets of the antibiotic-treated sows had lower alpha diversity and higher relative abundance of Escherichia at three days of age. At 10 weeks, they exhibited higher alpha diversity and lower abundances of Limosilactobacillus, as well as higher abundances of Prevotella and Clostridium sp. CAG-127. Antibiotic treatment decreased the piglets' average daily growth (ADG) (p=0.033). Increased alpha diversity at 10 weeks of age was associated with lower ADG (p=0.033). Oliverpabstia and Mitsuokella were positively, and CAG-127 negatively associated with ADG. Gestational antibiotics may have adverse effects on microbiota and growth of the offspring, even if the maternal microbiota recovers pre-antibiotic treatment status by parturition.