Abstract
Twenty macropods from five locations in Queensland, Australia, grazing on a variety of native pastures were surveyed and the bacterial community of the foregut was examined using 454-amplicon pyrosequencing. Specifically, the V3/V4 region of 16S rRNA gene was examined. A total of 5040 OTUs were identified in the data set (post filtering). Thirty-two OTUs were identified as ‘shared’ OTUS (i.e. present in all samples) belonging to either Firmicutes or Bacteroidetes (Clostridiales/Bacteroidales). These phyla predominated the general microbial community in all macropods. Genera represented within the shared OTUs included: unclassified Ruminococcaceae, unclassified Lachnospiraceae, unclassified Clostridiales, Peptococcus sp. Coprococcus spp., Streptococcus spp., Blautia sp., Ruminoccocus sp., Eubacterium sp., Dorea sp., Oscillospira sp. and Butyrivibrio sp. The composition of the bacterial community of the foregut samples of each the host species (Macropus rufus, Macropus giganteus and Macropus robustus) was significantly different allowing differentiation between the host species based on alpha and beta diversity measures. Specifically, eleven dominant OTUs that separated the three host species were identified and classified as: unclassified Ruminococcaceae, unclassified Bacteroidales, Prevotella spp. and a Syntrophococcus sucromutans. Putative reductive acetogens and fibrolytic bacteria were also identified in samples. Future work will investigate the presence and role of fibrolytics and acetogens in these ecosystems. Ideally, the isolation and characterization of these organisms will be used for enhanced feed efficiency in cattle, methane mitigation and potentially for other industries such as the biofuel industry.
Highlights
Macropods are marsupials belonging to the family Macropodidae that includes kangaroos and wallabies
Rarefaction was performed at the Operational Taxomonic Units (OTUs) level, and rarefaction curves demonstrated firstly: diversity differed between individual samples
Alpha diversity measures indicated that M. rufus forestomach samples had significantly higher bacterial diversity than the other host species according to: PD and number of OTUs (Table 2)
Summary
Macropods are marsupials belonging to the family Macropodidae that includes kangaroos and wallabies. Macropods are herbivorous and can be divided into grazers (feed on perennial native grasses/sedges), browsers (feed on small shrubs) and mixed feeders (both grazers and browsers). The stomachs of grazing macropods have an enlarged forestomach region, the sacciform and tubiform, where microbial fermentation of ingested plant material takes place and the hind-stomach, which secretes hydrochloric acid and pepsinogen [1]. In common with other foregut fermenting herbivores, the sacciform and tubiform regions possess a consortium of microbes that are involved in enteric fermentation [2,3]. There are many similarities between macropod foregut microbial fermentation and fermentation in the rumen of ruminants, e.g. sheep and cattle, it has been demonstrated that there are significant differences in the digesta flow and digestion/absorption patterns [1]. It has been proposed that differences in digestion may occur due to physiological differences in the gut structure and the process of selection may have an effect on the microbial population [1]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
