Molecular characterization of the microbial communities in the subcaudal gland secretion of the European badger (Meles meles)

Abstract

Many mammals possess specialized scent glands, which convey information about the marking individual. As the chemical profile of scent marks is likely to be affected by bacteria metabolizing the primary gland products, the variation in bacterial communities between different individuals has been proposed to underpin olfactory communication. However, few studies have investigated the dependency of microbiota residing in the scent organs on the host's individual-specific parameters. Here, we used terminal restriction fragment length polymorphism analysis of the PCR-amplified 16S rRNA gene and clone library construction to investigate the microbial communities in the subcaudal gland secretion of the European badger (Meles meles). As the secretion has been shown to encode individual-specific information, we investigated the correlation of the microbiota with different individual-specific parameters (age, sex, body condition, reproductive status, and season). We discovered a high number of bacterial species (56 operational taxonomic units from four phyla: Actinobacteria, Firmicutes, Proteobacteria, and Bacteroidetes), dominated by Actinobacteria (76.0%). The bacterial communities of cubs and adults differed significantly. Cubs possessed considerably more diverse communities dominated by Firmicutes, while in adults the communities were less diverse and dominated by Actinobacteria, suggesting that the acquisition of a 'mature bacterial community' is an ontogenetic process related to physiological changes during maturation.

Bacterial communities in meerkat anal scent secretions vary with host sex, age, and group membership

“…Although bacteria in scent secretions are influenced by individual and group factors in meerkats and other animals (Theis et al 2012;Sin et al 2012), whether bacteria partly generate scent cues used in individual or group recognition remains unknown (Archie and Theis 2011). Although useful for investigating patterns of host variability, the culture-independent method used here does not allow the identification of bacteria phylotypes.…”

“…Although useful for investigating patterns of host variability, the culture-independent method used here does not allow the identification of bacteria phylotypes. Therefore, determining if meerkat scent gland secretions contain fermentative, odor-producing bacteria, as recently found in striped hyenas, Hyaena hyaena, spotted hyenas (Theis et al 2012;Theis et al 2013), and European badgers, Meles meles (Sin et al 2012), will require implementing next-generation sequencing methods. The rapid improvements and cost reduction of these methods promise to reveal much about the importance of bacteria in the production of social odors in animals.…”

Evidence for a bacterial mechanism for group-specific social odors among hyenas

“…Still, the 16S sequences that could be assigned to a genus represented 78 genera from nine different bacterial phyla. Collectively, the 15 prior surveys of specialized mammalian scent glands—covering 14 species from five mammalian orders—recovered bacteria from just 63 genera within five bacterial phyla631. Therefore, as expected, the next-generation sequencing approach used in this study afforded a far more comprehensive view of the bacterial communities inhabiting the specialized scent glands of a mammal than was previously available and, consequently, overturned the general conclusion from earlier studies that the bacterial diversity in integumental scent glands appears insufficient to underlie the observed diversity of chemical signals within scent marking mammalian species6.…”

Social Environment Has a Primary Influence on the Microbial and Odor Profiles of a Chemically Signaling Songbird

“…Although this hypothesis has been increasingly investigated in scent-marking mammals (Zomer et al, 2009;Sin et al, 2012;Theis et al, 2013;Leclaire et al, 2014), it has received less attention with respect to chemical signaling in birds (Whittaker and Theis, 2016). If symbiotic microbes contribute to their hosts' odor profiles, then host organs emitting the odors should be populated by communities of odor-producing microbes, and the microbial and volatile odor profiles of the organs should covary.…”