GROWTH AND NUTRIENT DIGESTIBILITY BY MALE AND FEMALE PENAEUS-MONODON - EVIDENCE OF SEXUAL DIMORPHISM

Quadruplicate groups of 10 Penaeus monodon were grown in tanks in mono sex and mixed-sex populations from 8.6 to 17.0 g (mean wet weight) ove r a period of 69 days. Measurements of feed intake and the apparent di gestibility of dietary protein and energy were made in the second and tenth weeks of the experiment. Monosex female prawns grew significantl y faster than monosex males and male prawns from mixed-sex tanks. The weight increment per moult of monosex females was greater (P < 0.05) t han that of monosex males, but no difference in intermoult period was seen between any of the groups. Feed intake of monosex females tended to be greater than that of monosex males but not significantly so. No significant difference between the sexes was detected for either appar ent digestibilities of dietary protein and energy or feed conversion.