HEMOGLOBIN LEVEL, METABOLIC-RATE, OPERCULAR ABDUCTION RATE AND SWIMMING EFFICIENCY IN FEMALE TRIPLOID BROOK TROUT (SALVELINUS-FONTINALIS)

Metabolic (oxygen consumption) rate, opercular abduction rate and tail beat frequency were determined in two strains of diploid and triploid female brook trout (Salvelinus fontinalis) while these fish swam at 0 .37+/-0.02 body lengths per sec in a Blazka respirometer. Total blood hemoglobin level was also measured and opercular condition examined. T otal blood hemoglobin levels in diploids and triploids were equal. The opercular abduction rate was the same in diploids and triploids (rega rdless of whether triploid opercular condition was good or poor) yet t riploids had a lower oxygen consumption rate than diploids, indicating that triploids take up less oxygen than diploids per opercular cycle. Tail beat frequency, an indicator of swimming effort, was the same in diploids and triploids, suggesting that triploids require less oxygen than diploids for a similar swimming effort.