Studies were conducted to investigate the effects of dietary vitamin C(VC)on growth,immunity and anti-ammonia-nitrite stress ability in juvenile black carp,Mylopharyngodon piceus(initial average weight 7.27±0.40 g).Six iso-nitrogenous and iso-energetic diets were formulated to supply at dosages of 0(control),16.3,33.9,69.1,137.8 and 277.5 mg/kg vitamin C diet,respectively.After feeding 8 weeks,according to specific growth rate,three group of 0,69.1 and 277.5 mg/kg of black carp were subjected to an ammonia-nitrite stress(20 mg/L)for 24 h.Resul...