biostudies-literatureFomenky BEGouvernement du Canada | Agriculture and Agri-Food CanadaGouvernement du Canada | Agriculture and Agri-Food Canada (Agriculture et Agroalimentaire Canada)14147https://www.ebi.ac.uk/biostudies/studies/S-EPMC6148029biostudies-literatureUnknown8(1)This study investigated the effect of supplementing the diet of calves with two direct fed microbials (DFMs) (Saccharomyces cerevisiae boulardii CNCM I-1079 (SCB) and Lactobacillus acidophilus BT1386 (LA)), and an antibiotic growth promoter (ATB). Thirty-two dairy calves were fed a control diet (CTL) supplemented with SCB or LA or ATB for 96 days. On day 33 (pre-weaning, n = 16) and day 96 (post-weaning, n = 16), digesta from the rumen, ileum, and colon, and mucosa from the ileum and colon were collected. The bacterial diversity and composition of the gastrointestinal tract (GIT) of pre- and post-weaned calves were characterized by sequencing the V3-V4 region of the bacterial 16S rRNA gene. The DFMs had significant impact on bacteria community structure with most changes associated with trScientific reportsDirect-fed microbial supplementation influences the bacteria community composition of the gastrointestinal tract of pre- and post-weaned calves.PMC6148029J-000218Chiquette JIbeagha-Awemu EMLessard MTalbot GBissonnette NChouinard YPFomenky BEDo DNfalseDirect-fed microbial supplementation influences the bacteria community composition of the gastrointestinal tract of pre- and post-weaned calves.This study investigated the effect of supplementing the diet of calves with two direct fed microbials (DFMs) (Saccharomyces cerevisiae boulardii CNCM I-1079 (SCB) and Lactobacillus acidophilus BT1386 (LA)), and an antibiotic growth promoter (ATB). Thirty-two dairy calves were fed a control diet (CTL) supplemented with SCB or LA or ATB for 96 days. On day 33 (pre-weaning, n = 16) and day 96 (post-weaning, n = 16), digesta from the rumen, ileum, and colon, and mucosa from the ileum and colon were collected. The bacterial diversity and composition of the gastrointestinal tract (GIT) of pre- and post-weaned calves were characterized by sequencing the V3-V4 region of the bacterial 16S rRNA gene. The DFMs had significant impact on bacteria community structure with most changes associated with tr2018-01-01T00:00:00Z2018 Sep2026-06-17T06:12:18.386Z2025-04-20T04:06:31.949ZS-EPMC61480293023756510.1038/s41598-018-32375-5