Effects Of Biotin On Growth Performance And Immunity In Broilers

The objective of this experiment was to study the effects of different biotin levels (deficiency, sufficiency and surplus) on growth performance and physiological and biochemical characteristics in broilers of 0-7 weeks. In the experiment, 576 AA broilers of 1 day were allocated into 4 treatments, 9 replicates per treatment, 16 broilers per replicate and the sex ratio was 1:1. The basal diet was wheat-casein-fish meal diet that had no additive biotins. Biotin was added in the basal diet at three different contents 0.3 mg/kg, 0.9mg/kg and 2.7 mg/kg. There were 4 kinds of treatments including the control of basal diet. The result showed as follows. (1) Biotin deficiency inhibited severely feed intake and growth rate. The ADG and ADFI of the control were lower significantly than that of the biotin addition treatments(P<0.01), but there was no significant difference among the biotin addition treatments(P>0.05). (2) Addition of biotin increases phospholipid and HDL levels in serum, and the difference between 0.9mg/kg addition treatment and control was significant(P<0.01). There was no significant difference among the biotin addition treatments(P>0.05). Addition of biotin had almost no influence upon LDL, Triglyceride and cholestero levels in serum. It maybe concluded that biotin mostly influences the metabolism of phospholipid. (3) Addition of biotin increased insulin and growth hormone content(P>0.05),and significantly decreased glucagons content in serum (P<0.05). The experiment aimed to investigate systematically the effect of biotin on immune organs development, immune response in broilers. 400 AA broilers of 1 days were allocated into 4 treatments, 5 replicates per treatment, 20 broilers per replicate. The basal diet was wheat-casein-fish meal diet. Biotin was added in the basal diet at 0.3 mg/kg, 0.9 mg/kg and 2.7 mg/kg. There were 4 diets including the control of basal diet. The results showed as follows: (1)Biotin deficiency impaired the development of immune organs and reduced their weight index .Addition of biotin enhanced their development and elevated their weight index. (2) Inclusion of biotin enhanced humoral immune response, which elevated serum globin. The antibody titer to Newcastle and IgG content were elevated by addition of biotin. (3) Biotin supplementation enhanced cellular immune response, Addition of biotin enhanced significantly B-lymohocyte and T-lymphocyte transformation ratio in blood.