To investigate the effects of alfalfa (Medicago sativa L.) meal on the growth performance, muscle quality and serum antioxidant index of grass carp (Ctenopharyngodon idella), five isonitrogenous and isolipidic diets (crude protein: 32.0%, crude fat: 4.12%) were formulated with 0 (control group), 5%, 10%, 15% and 20% alfalfa meal, respectively. Juvenile grass carp [initial weight of (50.04±0.04) g] were fed for 61 days. The results showed that: (1) Compared with the control group, the specific growth rate significantly decreased in the group wi...