| This study was undertaken to investigate the effects of coated acidifier on the production performance of yellow broiler chicks.Method:In a completely randomized design,3751-d-old yellow broiler chicks were divided into five treatment groups of three replicates,15chicks each. The first group (group â… ) was served as control and fed the basal diets. The second group (group â…¡) was fed the basal diets supplemented with antibiotics. While, the other three groups were received the basal diet supplemented with coated acidifier at levels of0.1%(group â…¢),0.3%(group â…£) and0.5%(group V) of diet, respectively.Results:1Performance28th day, the body weight and body weight gain of group V were significantly higher than group â… (P<0.05), and there were no significant difference among group â…¡, â…¢, â…£and â…¤. The feed intake of group â…¡,â…¢,â…£and â…¤ were significantly higher than group â… (P<0.05). The daily gain of group V was significantly higher than group â… (P<0.05) and not significantly higher than group â…¡ (P>0.05).63rd day, the body weight, body weight gain and daily gain of group â…¡,â…¢,â…£andâ…¤ were significantly higher than group â… (P<0.01). The difference of feed conversion efficiency and survival rate among groups were not significantly (P>0.05).The slaughter weight, carcass weight, half net thorax weight, eviscerated weight, breast muscle weight and leg muscle weight of groupâ…¢,â…£andV were significantly higher than group â… (P<0.01). The half net thorax weight, eviscerated weight, breast muscle weight and leg muscle weight of group IV were significantly higher than group â…¡ (P<0.01or P<0.05). The percentage of breast and leg muscle rate of groupâ…£ were significantly higher than group â… (P<0.05).2The content of nitrogen and crude ash in excrement of broiler28th day, the content of nitrogen in excrement of group V was significantly lower than group â… (P<0.05).56th day, the content of nitrogen in excrement of groupâ…£ was lower than group â… (P<0.05).3Intestinal pH28th day, the pH of duodenum of group â…£and â…¤ were significantly lower than group â… (P<0.05). The pH of duodenum of group â…¤ was significantly lower than group â…¡ (P<0.05).63rd day, the pH of glandular stomach of group V was significantly lower than group â… (P<0.05). The pH of duodenum of groupâ…£was significantly lower than group â… (P<0.05).4Duodenum digestive enzyme28th day, the activity of trypsin and amylase of group â…£andâ…¤ were significantly higher than group â… (P<0.05).63rd day, the activity of trypsin and amylase of groupâ…£was significantly higher than group â… (P<0.05).5Caecal microflora28th day, the number of E-coli of group V was significantly lower than group â… (P<0.05) and the number of lactic acid bacillus of group â…¤ was significantly higher than group â… (P<0.05).63r day, the number of E-coli of group â…£was significantly lower than group â… (P<0.05) and the number of lactic acid bacillus of groupIVwas significantly higher than group â… (P<0.05).6Serum biochemical index28th day, the content of TP in the serum of groupIVandVwere significantly higher than group(P<0.05). The AKP, CAT and T-AOC of group â…¤ were significantly higher than group â… (P<0.05).63rd day, the AKP of groupâ…¢and â…£were remarkably improved when compared to group â… , and the BUN were decreased (P<0.05). The CAT of groupâ…£and â…¤ were significantly higher than group â… (P<0.05). The T-AOC of groupIVwas higher than group â… , and the MDA was lower (P<0.05).7Immune organ index28th day, comparing with group â… , it could remarkable improve spleen index in group â…£and E (P<0.05).63rd day, the spleen index of groupâ…¢was significantly higher than group â… (P<0.05). The bursa index of groupIV was significantly higher than group â… (P<0.05).8The intestinal morphology and mucosal immunity28th day, the duodenal villus height of group â…¡,â…¢,â…£and â…¤ were significantly higher than group â… (P<0.05or P<0.01).63rd day, the duodenal villus height of groupâ…£was significantly higher than group â… (P<0.05).28th day,the intraepithelial lymphocytes of jejunum of group â…¤ were significantly higher than group â… (P<0.05). The nunber of duodenal mucous cells of group â…¤ were significantly higher than group â… (P<0.05). The number of mucous cells in ileum of the group â…£ and â…¤were significantly increased than group â… (P<0.05). The S-IgA cells in duodenum, jejunum and ileum of group â…¢,â…£and â…¤were significantly higher than group â… (P<0.05or P<0.01).Conclusion:1The use of coated acidifier on yellow broiler chicks feed can improve the performance of broilers.2Appropriate amount of coated acidifier can improve the digestive absorption on nutrient substance for yellow broiler chicks, related to the change of pH, the raise of digestive enzyme activity, optimization of microbial flora structure and the improvement of serum biochemical markers.3The suitable dosage of coated acidifier in the diet of broilers was0.3%-0.5%. |
