Diversity and novelty of the gut microbial community of an herbivorous rodent (Neotoma bryanti)

Abstract

Mammalian herbivores host diverse microbial communities to aid in fermentation and potentially detoxification of dietary compounds. However, the microbial ecology of herbivorous rodents, especially within the largest superfamily of mammals (Muroidea) has received little attention. We conducted a preliminary inventory of the intestinal microbial community of Bryant's woodrat (Neotoma bryanti), an herbivorous Muroidea rodent. We collected woodrat feces, generated 16S rDNA clone libraries, and obtained sequences from 171 clones. Our results demonstrate that the woodrat gut hosts a large number of novel microorganisms, with 96% of the total microbial sequences representing novel species. These include several microbial genera that have previously been implicated in the metabolism of plant toxins. Interestingly, a comparison of the community structure of the woodrat gut with that of other mammals revealed that woodrats have a microbial community more similar to foregut rather than hindgut fermenters. Moreover, their microbial community was different to that of previously studied herbivorous rodents. Therefore, the woodrat gut may represent a useful resource for the identification of novel microbial genes involved in cellulolytic or detoxification processes.

Experience matters: prior exposure to plant toxins enhances diversity of gut microbes in herbivores

“…Woodrats possess a foregut chamber (termed ‘pregastric stomach’ in Kohl et al . ) that consists of non‐secretory epithelium (Carleton ), and so should maintain a more neutral pH and facilitate more microbial growth compared with the acidic, gastric chamber. Interestingly, the microbes present in the faeces of woodrats more closely resemble the patterns observed in distantly related, foregut fermenting Artiodactyls rather than closely related rodents, suggesting that this foregut structure and its resident microbes could be important to host physiology (Kohl et al .…”

The Gastrointestinal Tract of the White-Throated Woodrat (Neotoma albigula) Harbors Distinct Consortia of Oxalate-Degrading Bacteria

“…Populations of the white-throated woodrat, N. albigula, consume a diet comprised almost entirely of the oxalate-rich Opuntia cactus (37). Woodrats have a complex, segmented gut, with a large hindgut fermentation chamber (cecum) in addition to a foregut chamber, proximal to the stomach, which also harbors a diverse microbial population (2,39,40). The foregut community structure shifts in response to dietary toxins and may function in the degradation of toxins (2).…”

A Pharm-Ecological Perspective of Terrestrial and Aquatic Plant-Herbivore Interactions

“…Curiously, none of the players in this system (microbe, plant, herbivore) have a long evolutionary history with one another. In addition to this example, detoxification of PSMs by gut microbes has been suggested for the unique and diverse microbial community found in the gut of a herbivorous rodent, the woodrat (Kohl et al, 2011). Moreover, the diversity of the microbial community appears to be a function of the host's evolutionary experience with PSMs such that more diverse communities are present in herbivores with previous experience to particular PSMs compared to novel ones (Kohl and Dearing, 2012).…”

“…Another function of gut microbes might be the detoxification of ingested PSMs (Chandler et al, 2008;Dearing et al, 2005;Foley et al, 1999;Kohl and Dearing, 2012;Kohl et al, 2011). There is at least one spectacular example of this phenomenon in domestic ruminants.…”