Effect of Cothurnia variabilis and Epistylis gammari (Ciliophora: Peritrichia) on Metabolic Rate of the Crayfish Cambarellus (Cambarellus) montezumae

Peritrichs usually settle on the external surface and gills of crustaceans. However, their physiological effect host has not been studied. Respiratory rate is a susceptible index for some factors that affect an organism. To test if ciliates attached to crustacean have effect, we measured oxygen consumption in closed system. Crayfish Cambarellus (Cambarellus) montezumae were collected Lago Xochimilco Mexico City isolated chambers. Two peritrich species, Cothurnia variabilis (32.5%) Epistylis gammari (67.5%), observed gills. The metabolic was evaluated by with polarimetric oximeter. Statistical analyses demonstrated density crayfish above ~50 individuals increased positive correlation epibiont density. We conclude C. E. ciliate epibionts gill cause increase rate.