Abstract:

100 one-day-old three buff chickens for an experimental period of 8 weeks, were randomly allotted into 5 groups each with two replicates, each replicate was ten chickens. The control group was provided with the basal diet, the antibiotic group was fed with basal diet supplemented with enrofloxacin at the level of 0.2%, the other groups were fed basal diet supplemented with probiotics YS at the level of 0.5%,1.0%,1.5% respectively. The results showed that probiotics YS could increase average daily gain and markedly reduce ratio of feedingstuff and gain weight; the maximum of average daily gain was probiotics YS at the level of 1.5% , was more 22.39% than control group; to three buff chickens, probiotics YS could increase the content of calcium, phosphorus, total protein, albumin, globulin, lysozyme, IgG, IgA in serum, and convert ratio of lymphocyte, and idexes of spleen, thymus, bursa; the suitable additive amount of probiotics YS in the basal diet of three buff chickens was 1.0%～1.5%.