Abstract
To investigate the composition and colonization of intestinal microflora in Thoroughbred foals, meconium (immediately after birth), and feces (at 3, 7, 14, 30 and 60 days after birth) were obtained from 27 foals born at 4 different breeding farms in Hokkaido, and were analyzed to determine the microflora and the content of short-chain fatty acids. The specimens were also examined for diarrhea-causing pathogens such as rotavirus and Salmonella. Meconium was confirmed to be free of bacteria. All fecal samples from 3-day-old foals contained an average of 109.4 organisms per gram wet weight feces. These included Bacteroidaceae, Enterobacteriaceae, enterococci, and lecithinase-positive clostridia. Detection rate of lactobacilli, staphylococci and Bacillus sp. in the feces from 3-day-old foals were 81, 50 and 62%, respectively. The changes in the detection rate and the number of bacteria over time after birth were different between bacterial species. Identification of the coliform group and lecithinase-positive clostridia was performed. The majority of the coliform group were identified as Escherichia coli, but type O-157 was not detected. Alpha-toxin producing Clostridium perfringens, suggested to be related to equine diarrhea, was detected at high levels in all specimens taken at 3 and 7 days, but was undetectable in any of specimens obtained at 60 days, indicating that this microorganism only colonizes the gut transiently from immediately after birth. No rotavirus or Salmonella was detected throughout the study period.
