Meeting Abstract
The capability of an organism to metabolize nutrients is crucial for fueling growth, facilitating development, and sustaining immune function, and variation in the gut microbiome during early life stages of an organism is often associated with altered host phenotypes and increased disease susceptibility. However, the biochemical mechanisms by which microbial communities affect an organism’s health across ontogeny remain poorly understood. The Warne lab has recently demonstrated that in larval amphibians hatching constitutes a critical window for establishment of a gut microbiome, and gut bacterial diversity, specifically the ratio of Firmicutes to Bacteroidetes, influences development rate, growth, and mortality rate due to Ranavirus infection – an emerging disease for ectothermic vertebrates. Consequently, we tested how targeted manipulation of the gut microbiome and a prebiotic treatment can be used to modulate host development and stress response phenotypes. Through gut microbiome manipulation at hatching in these larval frogs and the subsequent prebiotic dietary treatment with a digestion resistant starch, we show that the gut microbiomial community structure affects growth, development, metabolism, and corticosterone responses to stress exposure. Specifically we found that (1) larvae with a disrupted gut microbiome exhibit significantly slower growth and development rates; while (2) disrupted larvae provided the starch experienced a rescue effect whereby they not only recovered growth rates compared to controls, but also exhibited significantly increased development rates; and (3) altered corticosterone responses to an external handling stressor. These results suggest gut microbiome and potentially metabolite profiles can be modulated to induce targeted effects on host function and health.
