The effect of diet quality on oxygen consumption in the supralittoral isopod Ligia pallasii

Abstract

1. 1. The effect of diet quality on rate of oxygen consumption in the sea slater Ligia pallasii was studied using natural diets of seaweeds and artificial diets of chemicals, the latter varying in content of carbohydrate and amino-acid nutrients. 2. 2. Diets of the red alga Porphyra sp. and the green alga Ulva lactuca caused a 32% decrease in rate of oxygen consumption over a 30-day period. 3. 3. A chemical diet with 25% less amino acids caused an increase in rate of oxygen uptake of 34% over a 20-day period. 4. 4. Dietary effects on rate of oxygen uptake in Ligia correlated positively with nutritional quality of the foods, as evidenced by growth, supporting the hypothesis that nutritionally balanced diets are associated with lower metabolic rates and, hence, with lower demands for oxygen, than nutritionally unbalanced ones.