Effects of Clenbuterol,Genotype,and Feeding Method on Bodyweight Gain of Meat Rabbits

S8; Four-factor and three-level orthogonal experimental design(L9(34))was used in the experiment.The effects of three genotypes:Germany SAB three-bred-cross rabbits(S2),New Zealand purebred(N),and crossbred rabbits(ON);three levels of Clenbuterol treatment: 1 ng.g-1,2 ng.g-1and 3 ng.g-1,and three feeding methods:5-day,7-day and 10-day withdrawal period after two weeks of feeding Clenbuterol(CL)on bodyweight gain were evaluated.CL apparently improved average daily gain(ADG)of rabbits.70-day ADG of 5-day and 10-day withdrawal were higher than that of 7-day withdrawal,70-day ADG of S2 genotype was significantly higher than that of the control and N genotype was significant.Genotype,additive dose and feeding method had significant effects on overall-stage ADG.ON genotype,2 ng.g-1 dose and 5-day withdrawal feeding method was the best.Responses of different genotype to Clenbuterol appeared different at experimental prophase or whole experimental period.