Effect of protein and lipid levels in diets for female red claw crayfish Cherax quadricarinatus on quality of offspring (juvenile), with emphasis on growth performance, biochemical composition and stress resistance to low oxygen, high ammonia and salinity

This study measures the effect of protein and lipid levels in broodstock diet on the quality of juvenile Cherax quadricarinatus. Diets with different contents of crude protein (180, 250, 310, 370 g kg^-1) and lipids (30 and 70 g kg^-1) were offered to female crayfish. Juveniles were used to assess initial weight (IW), biochemical composition (BC) and survival to stress tests (ST). After 50 days, growth was estimated. No significant effects of broodstock diet on IW and BC of juveniles were detected. Protein content (PC) significantly influenced growth (P < 0.05), with an optimum level of 250 g kg^-1, representing a weight gain of 1.17 g (98.08% body weight). PC significantly influenced survival of juveniles exposed to ST (P < 0.05). Results from fitting dose-response models indicated that maximum survival was obtained with PC above 261, 258 and 312 g kg^-1 for hypoxia, salinity, ammonia tests. No significant effect of dietary lipid level was observed on growth and survival to ST, except for greater survival to ammonia ST at lipid content of 70 g kg^-1. We recommend feed with PC of 260 g kg^-1 to simultaneously enhance growth and quality of juveniles.