Protein level and quality are of utmost important to growth of fish. Although common carp is a popular experimental fish, contradictory results on protein requirement have been reported by different works. An experiment lasting for 3 months included different protein level in 4 diets: 38.1%, 38.5%, 41.5% and 43.7%. Carp yearlings (body mass 95.5g) were fed in order to investigate effects on growth rate. There were no significant differences in the final individual weights, weight gains, specific growth rates (SGR), feed conversion rate (FCR) and thermal growth coefficient (TGC) among fish fed different diets (P>0.05)
