EFFECTS OF CLOSTRIDIUM BUTYRICUM SUPPLEMENTATION ON FECAL MICROBIOTA AND METABOLITES IN CAPTIVE RED KANGAROO (MACROPUS RUFUS).

The red kangaroo (Macropus rufus) is a prominent marsupial species native to Australia and is kept in zoos worldwide. Captive red kangaroos are often plagued with several diseases, such as lumpy jaw, incurring high treatment costs. Recent research suggests a significant link between the gut microbiota and various diseases in many species, indicating potential benefits of probiotics in maintaining health. The microbiota of the digestive tract of red kangaroos has been reported; however, the fecal microbiota and any compositional changes in this microbiota caused by probiotic intervention remain to be elucidated. Herein, the effects of the probiotic Clostridium butyricum, which produces the short-chain fatty acid butyrate, on fecal microbiota and metabolites in red kangaroos were investigated. Fecal samples were collected from six red kangaroos free from signs of diseases (three males and three females, aged 1-2 yr) during C. butyricum supplementation and suspension periods. Fecal C. butyricum levels decreased during the suspension period and increased upon resumption by quantitative PCR analysis. Despite changes in C. butyricum levels, fecal concentrations of measured short-chain fatty acids remained unchanged. Total microbiome analysis showed no significant differences by C. butyricum supplementation. Functional predictions indicated alterations in microbial community functions, such as activating penicillin and cephalosporin biosynthesis and inactivating the bacterial secretion system during C. butyricum supplementation. Metabolomic analyses identified significant changes in pathways related to amino acid degradation and metabolism, fatty acid biosynthesis, glycolysis and glycogenesis, and the citrate cycle (the tricarboxylic acid cycle), suggesting that C. butyricum supplementation affects metabolism independent of microbiota composition. These findings suggest that C. butyricum alters metabolism. However, this study's kangaroos were supplemented with C. butyricum prior to the study period, so its impact could not be verified. Further study is also required to determine how these changes might contribute to maintaining health in captive red kangaroos.