Molecular Detection of Age-Related Abundance and Diversity of Bifidobacterium spp. in Pastured Goats

Bifidobacterium spp. are among bacteria being developed as probiotics for farm animals. Understanding diversity of the normal gut inhabitants is a prerequisite to developing species-specific probiotics strains that are likely to establish in the host. For many farm animals including goats, the normal gut Bifidobacterium inhabitants have not been characterized including age based differences. The objective of this exploratory study was to gain preliminary understanding of abundance and diversity of Bifidobacterium species in goats of different ages. Molecular methods have given scientists fast methods for exploratory insights into previously uncharacterized microbiomes. Consequently, in this study we utilized molecular assays using genus and species specific primers to characterize Bifidobacterium in pastured goats. Although Bifidobacterium were detected in all ages, younger animals had higher counts than older goats. In goats below six months of age, B. angulatum, B. dentium, B. gallicum, B. animalis sub animalis, B. longum and B. catenulatum were detected. In goats six months and older, B. dentium and B. gallicum were predominant. In some goats however, the specific strains could not be identified with the currently available primers indicating there are goat specific unique strains that are yet to be characterized. Further research to characterize and isolate Bifidobacterium in goats are needed for future probiotic applications. In conclusion, Bifidobacterium spp. were common in all age groups of pastured goats but more abundant in pre-weaned goats compared to goats over six months. In addition age related differences in the diversity of Bifidobacterium spp. in goats were reported.