FEDEWA, L A; University of Georgia – Institute of Ecology: The effect of ontogeny on intestinal bacterial loads in the narrow-mouthed toad (Gastrophryne carolinensis)

Declines in amphibian populations have been documented throughout most of the world. Pathogens have been implicated as the primary cause for a large number of these declines. In some of these instances, opportunistic bacterial pathogens have formed secondary infections. These bacterial infections were primarily found in amphibians with compromised immune systems. A morphological metamorphosis occurs during the development of most amphibians resulting in a biphasic lifestyle. During this metamorphosis, natural changes have been recorded within the amphibian immune system. Therefore, developmental transformations in the amphibian immune system may present a period of increased susceptibility to environmentally omnipresent pathogens such as bacteria. In this study, intestinal bacteria from narrow-mouthed toads (Gastrophryne carolinensis) were analyzed during larval and metamorphic development to determine life stages at which individuals are most susceptible to enteric diseases.