CLINOSTOMUM MARGINATUM METACERCARIA INCIDENCE IN SMALLMOUTH BASS FROM A NORTH ARKANSAS STREAM AND IN VITRO OXYGEN CONSUMPTION STUDIES

Smallmouth bass (Micropterus dolomieui) captured from Crooked Creek (Marion Co., Arkansas) in the summersof 1977 and 1 987 werefound to have a high incidence of infection with the metacercaria of Clinostomum marginatum (yellow grub). Of 41 fish collected in 1977, 32 (78%) were found infected with metacercariae with some fish containing large numbers of parasites. The number of larvae per fish ranged from 1 to 184, withan average of 23.2 ± 38 per smallmouth. Eighty-six percent of the bass collected in 1987 were found positive for C. marginatum. The number of metacercariae per fish ranged from 1 to 227 withan average of 32.7 ± 54 per fish. Fish from both collection groups ranged in size from 12 to 34 cm. No significant correlation could be found between the number of metacercariae per fish and the length of the host. Usingmetacercariae removed fromhost tissue, the effect on oxygen consumption by glucose, serotonin and insulin, singularly orin combination, wasmeasured by manometric methods. Glucose alone did not stimulate oxygen utilization, serotonin alone and with glucose was stimulatory, and insulin with glucose also increased oxygen consumption.