Modulatory effect of temperature on the influence of dietary linolenic (18: 3 n-3) and linoleic (18 : 2 n-6) acids on the gonadal recrudescence in Clarias batrachus (L.)

During the late postspawning phase, freshwater catfish Clarias batrachus fe d a diet rich in linseed oil (18:3 n-3) (LSO) and 13L:11D photoperiod and a t 28 degrees C showed increases in ovarian weight and plasma levels of test osterone and oestradiol-17 beta, and in concentrations of free fatty acids (FFA), monoglycerides (MG), diglycerides (DG), triglycerides (TG), phosphol ipids (PL) and esterified cholesterol (CE) in the liver, plasma and ovary. In fish fed a diet rich in sunflower oil(18:2 n-6) (SFO) under the same con ditions, plasma testosterone decreased sharply, concentrations of FFA, DG a nd TG increased in the liver and plasma and ovarian levels of TG and CE dec reased. Neither diet was gonadostimulatory when fed at 18 degrees C. (C) 20 00 The Fisheries Society of the British Isles.