CHARACTERIZATION OF THE RUMEN MICROBIOME FROM BIRTH TO ADULTHOOD

The cooperative relationship between the ruminant and its resident microbiome has evolved over millions of years and has critical implications for our everyday lives with respect to food sustainability, environment, renewable energy and economy. Ruminants, which have evolved into an obligatory co-dependence with their gut microbiome, represent an ideal model for the study of evolutionary dynamics in host–microbe symbiosis. Moreover, the highly complex microbial ecosystem of the rumen and its confined nature provide a perfect system for the study of complex microbial communities and evolutionary relationships within them. Hence, an understanding of this complex ecosystem has major economic and sociological implications. This work focuses on the colonization dynamics of the cow’s reticulorumen by its bacterial species. Newborn ruminants gradually acquire their microbiota following birth in a process whose biology and dynamics are poorly understood. Previous studies have suggested that the reticulorumen bacterial composition changes dramatically with age. However, these studies examined mostly culturable reticuloruminal species, representing only a small fraction of this environment’s microbiota. As a result, the colonization steps of reticulorumen bacteria remain a mystery. In this study next-generation sequencing wes utilized in order to create a high-resolution picture following the establishment of the rumen microbiota from birth to adulthood. Our results suggest that rumen bacterial succession is a deterministic process that shows high degree of repetitiveness across individuals.