Nurturing healthy gut microbiome: route to increased disease resistance in ruminants

Abstract Text: Perturbations in gut microbiota colonization during early life have been shown to present long lasting influences to the host immune responses, health and metabolism as well as subsequent microbial succession. These perturbations can be caused by nutritional imbalances, differing feeding methods, nutritional regimes and antibiotic treatments during the early life. Management of ruminants can vary significantly due to different feeding practices and it relies heavily  on antibiotics prevention/treatments for diarrhea and pneumonia in pre-ruminants. However, our understanding on the influence of such management practices on gut microbiome as well as ruminant health and metabolism is very limited. Our recent study has revealed that feeding of heat-treated colostrum soon after birth enhances the colonization of beneficial bacterium, bifidobacteria, which is well-studied using mouse models and has been shown to have greater impact on mucosal immune system development as well as weight gain in children. Besides, the colonization of bifidobacteria in calf gut has been suggested as a preventive mechanism of pathogenic E. coli that causes neonatal calf diarrhea. The use of next generation sequencing approaches to study calf gut microbiome and linking the early microbial composition with that of calf phenotypes have reported that higher abundance of Faecalibacterium is associated with decreased diarrhea incidences and increased body weight, suggesting linkages between gut microbiome, calf health and growth. Moreover, diet-driven changes in rumen microbiome are related to the development of subacute ruminal acidosis, a prevalent metabolic disorder in adult cattle. Thus, understanding on gut microbiome and their link to gut/rumen development and metabolism will provide means to improve health in ruminants via microbial manipulation. Such manipulation methods towards nurturing a healthy gut microbiome not only improve the disease resistance in ruminants, but may also decrease the heavy antibiotic usage that is in practice in the industry.

Keywords: Disease resistance, gut microbiome,