Meeting Abstract
The Rusty Crayfish (Faxonius rusticus) is native to the Ohio River Basin in North America but has become an invasive species in other regions. Rusty Crayfish are dietary generalists and opportunists, feeding on both cellulose-rich and protein-rich food items that are seasonally available to them. As part of a larger study examining how different types of diets (cellulose-rich vs. protein-rich) influenced the gut microbiomes of Rusty Crayfish captured from native parts of their range, we examined how diet-induced changes in microbial diversity might be related to dietary preference at the end of the study period. The first behavioral experiment involved placing crayfish in food-choice arenas where they could orient toward and follow chemical cues emitted from the two food types enclosed in perforated plastic tubes. The second behavioral experiment was performed in home containers, and the crayfish were able to directly choose one of the two food types and, in contrast to the first experiment, consume it. In terms of the initial contacts with food items, in both experiments crayfish did not significantly choose one food type over another. However, in the first experiment, crayfish that had been maintained on a cellulose-rich diet made more total contacts with tubes containing cellulose-rich food. These crayfish also showed greater increases in cellulose-digesting bacteria in their guts during the housing period compared with crayfish fed on the protein-rich diet.
