The Importance of Microbiomes for Animal Health and Conservation

A recent article from the Smithsonian Magazine highlights the importance of animal gut microbiomes in conserving animal species, both in captivity and in the wild. Microbes help animals digest their food, defend them against disease and even contribute to nursing their babies. Consequently, animal ecologists, nutritionists, and veterinarians work alongside geneticists to illuminate the role of the animal microbiome in conservation and zoos. Most animals are specialized to feed on niche plants rich in fibers. However, most animals don’t have the enzymes necessary to break down these complex plant fibers, but their microbes may have them. Therefore, an unbalanced gut microbiome may result in deficiencies in animals such as sloths, pandas, or rhinos in breaking down complex plant fibers. For example, recent work illustrates that black rhinos under human care and in the wild differ in their gut microbiomes. Gut microbiomes of rhinos under human care were more suited to digest starchy foods, while wild black rhinos better handled breaking down complex fibers. Besides their dietary contributions, microbes also fend off animals from disease. Skin microbes of frogs and salamanders help in fighting off the deadly chytrid fungus. Further, cheetahs at the Smithsonian Zoo appear to get gut infections when harmful bacteria overpower good bacteria. Therefore, their treatment includes doses of good bacteria to recover their microbiome. The development of the animal microbiome starts from day one of infancy. In mammals, infants get their first source of microbes from their mother’s milk, which helps colonization of their gut bacteria and provides milk sugars that feed beneficial microbes and aid in the proper development of the infant immune system. In fact, animals are not exclusive in having microbiomes; even their habitats have unique microbiomes. Microbial communities are found in soil, root systems, and water, which in turn interact with animal microbiomes as they swim, roll in the dirt, or feed. The animal microbiome in isolation doesn’t tell the whole story when it comes to overall health; an animal’s environmental habitat is an important contributor as well. Exposure to the right microbes is important to consider for the health of animals in captivity and their success in reintroduction to the wild.