Microbiome And Its Relationship To Health
Microorganisms are life forms that are so small we cannot see them with the naked eye; we need a microscope to see them. Microorganisms live in all habitats, and some of them are best known for their ability to make us sick. For example, human pneumonia is often caused by the bacterium Streptococcus
Each member of the microbiota has its own collection of genes. Just as in humans, genes are the instruction set for making and maintaining individual organisms. Each microbial species has its own set of genes. The collection of genes within the microbiota is the microbiome. This collection of genes is vast and, in the human gut habitat, outnumbers the number of human genes1. Scientists can “read” these microbial genes using sequencing techniques to identify the microbial community in a given habitat.
Microbiome relationship to overall health
One habitat teeming with microorganisms is the animal gut. All animals, including humans, pets (dogs, cats, etc.), domesticated livestock (cows, sheep, etc.), and wild animals (hawks, deer, spiders, etc.) support an incredible number of microbes in their guts. In fact, current estimates suggest that the number of microbial cells in the human gut is approximately equal to the number of human cells2. Without these microbes, animals would be unable to digest all of their food or develop a fully functional immune system.
The microbiome has an extremely wide impact on health
Microbes living in and on animals can affect animal health in a variety of ways. Some microbes are essential for health. For example, in the gut, microbes assist with digestion3. On the skin, microbes may be important for preventing allergy4. In contrast, some microbes are not good for health, potentially making an animal sick, or in the case of microbes living in the mouth, may affect the development of periodontal disease5,6. Although microbes with these extreme effects exist, most microbes are somewhere in between: some of them are slightly beneficial, some of them have no effect at all, and others are partially detrimental but not bad enough to make the animal sick. This gets even more complicated when we think about microbes affecting each other and how those microbial interactions may change the outcome with respect to animal health. For example, microbe X may help with food digestion only if microbe Y is absent. However, if microbe Y colonizes the gut, microbe X produces a toxin to kill microbe Y, and this toxin inadvertently causes inflammation of the intestinal walls.
Conditions that affect gut health
According to recent studies, disruptions to
Disrupting the microbiota is often unavoidable, and thus, in order to prevent loss of beneficial gut microbes, we need to do all we can to improve their ability to return their guts to a healthy, pre-antibiotic state.
Microbiome relationship to nutrition
The microbes in the gut help with digestion3, which means that they eat what their animal “host” eats. Thus, animal diet and nutrition has a strong impact on
We cannot completely answer these questions until scientists conduct more research. But we do know that certain components of diet affect particular members of the gut microbiota in dogs and cats. For example, the amount of protein and carbohydrates that dogs and cats eat can steer the gut microbiota towards having more bacteria of the Firmicutes type19. Too much protein might negatively alter the gut microbiota and impact dog health20. Experiments with potato fiber in dog diets have shown that this fiber source resulted in “favorable fermentation,” butyrate production, and increased abundances of “good” gut bacteria21,22. Examining gut bacteria by “reading” their DNA sequences has now become much more affordable, paving the way for more studies to test particular dietary components for their effects on gut microbiota and overall health. Moreover, pet parents can also have the gut microbiota of their pets characterized in order to improve pet diet and overall health.
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