Daisy Johnson, University of California, Davis, USA
Daisy Johnson1, Steve A. Frese1, and David A. Mills1
1. University of California, Davis
Milk is known to both seed and feed the microbes that colonize mammalian gastrointestinal tract. In particular, milk contains complex glycans that serve a prebiotic function enriching beneficial microbes in the mammalian colon. We hypothesize that the development of the gut microbiota in bovine mammals represents an interesting model to understand the co-association of milk glycans with specific milk enriched microbial populations. Pre-weaning management of dairy and beef calves occurs differently.
Beef calves are often nursed from their mother and fed hay ad libitum while dairy calves are typically given milk replacer and grain after an initial feeding of colostrum. In order to understand these pre-weaning gut microbiome changes, fecal swabs were collected from 9 beef calves and 22 dairy calves daily for the first two weeks and then weekly until they were fully weaned. Initial microbiota analysis of dairy calves indicates a pre-weaning predominance of Bacteroides species during the milk replacer feeding which decreases during weaning with an increase in Ruminococcaceae and Prevotella at weaning. Comparative analysis between the pre-weaned beef and dairy calf gut microbiomes will reveal both population and functional differences that arise from these two modes of pre-weaning feeding and aid in understanding how potential pathobiont populations (such as Escherichia coli) become established early on in these commercially important livestock.