The impact of environmental pollution on the gut microbiome of Tanzanian goats
Background: The impact of environmental pollution reaching and affecting the gut microbiome is rising. Pollution from vehicle emissions can release compounds harmful to both animal and environmental health, particularly in understudied sites.  Result: Here, we have investigated the potential effect of environmental pollution on the gut microbiome of Tanzanian goats grazing near a heavily trafficked road compared to goats living in a more rural setting. We identified 1,468 MAGs (of which 768 were novel species) and created a genomic database to which 52% of the bacterial community could be assigned. We find significant differences in the composition of the bacterial communities and resistomes between rural and road exposed goats, but not a major difference in AMR abundance. Genes involved in pollutant biodegradation were significantly more abundant in the microbiome of goats grazing along the road. This includes genes involved in degradation of naphthalene and toluene (both present in motor vehicle exhaust), as well as the detoxification enzyme, glutathione S-transferase.  Conclusion: These findings suggest living near a heavily trafficked road selects for xenobiotic degrading function within the goat gut microbiome, which might aid the host in detoxification of these compounds.