Next-Generation Sequencing Insights into the Oral Microbiome and Antibiotic Resistance Genes in Grey Wolves (Canis lupus)

The oral microbiome of apex predators such as grey wolves (<i>Canis lupus</i>) is colonised by complex microbial communities and plays a crucial role in the health of wild mammals, but remains poorly understood. In this study, a single pooled sample mixed from oral samples of 17 wolves <i>(Canis lupus)</i> hunted in Lithuania was investigated for the determination of a variety of oral microbiota, providing the first metagenomic insight into wolf oral microbiomes in Baltic countries. The aim of this study was to identify the zoonotic and antimicrobial resistance potential of the oral microbiota. The results revealed diverse microbiomes associated with periodontal health as well as microbiomes related to the environment. Unique microbial taxa potentially reflect the nutritional and ecological interactions of carnivores. Shotgun metagenomic sequencing yielded a total of 18,726,406 raw reads, and following quality trimming and filtering, 86.01% of these (16,106,613) were retained. Among the total reads, 45.15% (8,455,255) were identified as host-derived and were removed. The most common oral bacterial genera were <i>Pseudomonas</i> (50%) and <i>Psychrobacter</i> (22.6%). Metagenomic reads for zoonotic pathogens, including <i>Salmonella</i>, <i>Mycobacterium</i> spp., <i>Yersinia</i>, <i>Coxiella burnetii</i>, <i>Corynebacterium pseudotuberculosis</i>, and others, were also detected, suggesting that grey wolves are potential natural reservoirs of zoonotic infections. Genes encoding antimicrobial resistance to many classes of antibiotics were also detected. This research contributes to understanding wolf dietary habits, oral health, the carriage and possible risk of transmitting AMR, and social interactions.