Dairy calf microbiome and the potential effect of probiotics.

Activity: Talk or presentation typesOral presentation at Conference


From birth, a calf’s gastrointestinal tract (GIT) is rapidly colonised with a large variety of microbes. Bacterial diversity and composition in the GIT can have a significant impact on growth and health, which can influence nutrient metabolism, pathogenic defence, immune modulation, resistance/susceptibility to infection and production outputs. Supporting microbial diversity and ensuring the establishment of beneficial microbiota, while defending against pathogens is necessary to avoid digestive disease and disorders that can adversely affect calf health, performance and welfare. Probiotics are live microorganisms such as bacteria and yeast, that possess health effects in supporting intestinal health and GIT microbiome development. Saccharomyces cerevisiae boulardii (SCB) has been shown in human and calf studies to decrease diarrhoea. Assessing a probiotics ability to support beneficial bacteria, defend against pathogenic growth and support GIT health through antibiotic/medical intervention is important to ensure continued support of calf health and be of financial value to the producer.

The aim of this study was to examine faecal bacterial community composition and assess the potential impact a probiotic yeast strain has on GIT pathogen defence, antibiotic resistance and support of beneficial bacteria populations.

Faecal sample collection of 36 holstein heifer calves was conducted and samples were analysed via 16s rRNA gene V4 sequencing. Invitro testing of a probiotic yeast strain Saccharomyces cerevisiae var. boulardii CNCM I-1079 was conducted to assess Antibiotic susceptibility, Antimicrobial activity against bacterial pathogens and Microbial interaction with GIT-beneficial bacteria.

Dynamic changes were observed in faecal microbiome development across the sampling period. Samples at birth were highly variable, likely influenced by maternal, environmental and colostrum factors. SCB was observed to be resistant to Neomycin, Vancomycin, Ampicillin - these are frequently used as broad-spectrum antibiotics so consideration of impact to other bacterial species in the GIT is needed. Within management practices (such as disbudding), if Pronestesic is used as a local anaesthetic, according to the findings of this study SCB will be able to continue to provide supporting effects to the GIT microbiome and intestinal health. SCB exhibited various degrees of inhibitory activities against pathogenic bacteria, indicating a broad spectrum of inhibition patterns. Maximum inhibitory activity was observed against Clostridium difficile, followed by Salmonella, Enterococcus faecalis and E. coli. Beneficial bacteria tested were observed to have increased growth when interacting with the probiotic supernatant – demonstrating the metabolites produced by this probiotic have beneficial properties in supporting bacterial growth.
Period18 Apr 2024
Event titleThe Society of Feed Technologists Ruminant Conference
Event typeConference
LocationCoventry, United KingdomShow on map
Degree of RecognitionNational


  • Calf microbiome
  • Microbiome
  • probiotic
  • pathogenic bacteria
  • beneficial bacteria
  • antibiotic
  • dairy calf health
  • dairy calf
  • antibiotic resistance