Evaluation of practical diets containing various terrestrial protein sources on survival and growth parameters of redclaw crayfish Cherax quadricarinatus

Redclaw aquaculture has developed at a rapid pace during the past few years, yet no specialized diet for the species has been developed. The present study was designed to evaluate whether soybean-based diets containing either fishmeal (FM), poultry by-product meal (PBM), ground peameal (GPM) or distillers dried grains with solubles (DDGS) meal as a protein source are suitable for redclaw aquaculture. Juvenile redclaw crayfish Cherax quadricarinatus (0.125±0.025 g) were stocked into 20 rectangular tanks at a stocking density of 12.5 m−2 for 8 weeks. Crayfish in four replicate tanks were maintained on one of five diets formulated to contain 35% crude protein and 7.1% lipids. Each 100 g of diet contained 25 g of protein from soybean meal (SBM) and 10 g of protein from the alternative protein sources mentioned above. A fifth treatment that did not receive feed was included to account for growth from natural productivity. There were no significant differences in survival (86–90%), growth (3.84–4.98 g animal−1) or feed conversion ratio (2.10–2.79) of crayfish among the four treatments (P>0.05). Survival and growth of crayfish in the treatment that received no supplementary feed were significantly less than those in treatments offered experimental diets. Results of the present experiment suggest that SBM-based diets with PBM, FM, DDGS or GPM have similar effects on growth performance and survival of juvenile redclaw, C. quadricarinatus.