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Four isonitrogenous (350 g/kg protein) diets were formulated for juvenile red claw crayfish, Cherax quadricarinatus, with half of the dietary fish meal replaced by four commonly used plant protein sources (cottonseed meal, soybean meal, rapeseed meal and peanut meal). A diet without fish meal replacement was used as a control. An eight‐week growth trial was conducted to evaluate the growth and health of crayfish juveniles (6.71 ± 0.08 g) fed diets containing the five different protein sources. The weight gain and specific growth rate significantly decreased in the crayfish fed the peanut meal diet compared with those fed the control diet. Survival, hepatosomatic index and whole‐body proximate compositions were not significantly influenced by different dietary plant protein sources. Intestinal damage is accompanied by higher activities of glutathione peroxidase, alanine aminotransferase and aspartate aminotransferase, and decreased lipase activities were observed in the crayfish fed the peanut meal diet. Crayfish fed the rapeseed diet also showed the detached peritrophic membrane and the lower lipase activities than those in control. Moreover, the malondialdehyde content increased and acid phosphatase activity decreased in the haemolymph of crayfish fed the soybean meal diet compared with those fed the control diet. Compared with those fed the control diet, the significantly increased valine contents, the activities of alkaline phosphatase and amylase were found in the crayfish fed the cottonseed meal diet. All these results suggest that soybean meal, rapeseed meal and peanut meal were not suitable substitute sources of plant protein for fish meal because of their adverse influences. On the contrary, cottonseed meal can be a good choice for fish meal replacement in the diet of juvenile Cherax quadricarinatus, as it does not have adverse effects on growth and could even increase amino acid nutrition, immunity and digestion.

Five dietary lipid sources (fish oil, soybean oil, palm oil, rapeseed oil and linseed oil) were evaluated in juvenile red claw crayfish, Cherax quadricarinatus, based on the response of growth, antioxidant capacity, intestine histology, whole‐body composition, fatty acid nutrition and lipid metabolism. Crayfish were fed in quadruplicate net cages for 8 weeks. Crayfish fed diets with fish oil, soybean oil and linseed oil obtained significantly higher weight gain and specific growth rate than those fed the other two diets. Survival, condition factor and hepatosomatic index were not significantly affected by lipid sources. Lipid sources also do not affect the whole‐body composition of crayfish. Serum SOD, T‐AOC and GSH‐PX activities of crayfish fed the palm oil and rapeseed oil diets had a significantly lower value than those fed other diets. The minimum concentrations of MDA have been observed in crayfish fed the soybean oil diet. The activity of ACC in the hepatopancreas of crayfish fed the linseed oil diet showed the highest value, and the CPT‐1 activity was not significantly affected by different lipid sources. Crayfish fed the soybean oil diet showed significantly higher TC and TG contents in hepatopancreas than those fed other diets. Crayfish fed linseed oil diet had a significantly higher percentage of EPA, C18:3n−3 and Σn−3 PUFA in muscle than those fed other treatments. Most of the fatty acid compositions in the hepatopancreas had a close correlation to fatty acid compositions in diets. All findings in this study indicate that soybean oil is the advantageous lipid source for juvenile C. quadricarinatus which can reflect in satisfactory growth performance, antioxidant capacity and fatty acid nutrition of edible tissues.