Effects of Clostridium butyricum on growth performance, nitrogen metabolism, intestinal morphology and cecal microflora in broiler chickens

A total of 600, 1 day old male Lingnan Yellow broiler chickens were used to investigate the effects of Clostridium butyricum (C. butyricum) on growth performance, nitrogen metabolism, intestinal morphology and cecal microflora in broiler chickens. The birds were randomly assigned into 5 treatments (6 replicate pens per treatment with 20 birds per pen) and fed the same antibiotic-free basal diets during a 42 days feeding experiment. The treatments were as follows: no addition (Control), 2.5 x 10(7) cfu C. butyricum kg(-1) of diet (CB1), 5x10(7) cfu C. butyricum kg(-1) of diet (CB2), 1x10(8) cfu. C. butyricum kg(-1) of diet (CB3) and 10 mg colistine sulfate kg(-1) of diet (Antibiotic). Compared with the control birds, birds fed either CB1 or CB2 or antibiotic diet had greater (p<0.05) Body Weight (BW) on day 21 and 42 and higher (p<0.05) Average Daily Gain (ADG) from day 1-42. Birds fed C. butyricum or antibiotic diet had lower (p<0.05) Feed-to-Gain ratio (F:G) than the control birds from day 1-42. Dietary C. butyricum decreased (p<0.05) the concentration of serum Uric Acid (UA) compared with the control diet on day 21. Supplementation with CB2 or CB3 decreased (p<0.05) serum ammonia concentration compared with the control diet on day 21 and 42. Birds fed C. butyricum diet had higher (p<0.05) ileal villus height than the control birds on day 21 and 42. Birds fed CB2 or CB3 diet had lower (p<0.05) ileal crypth depth than the control birds on day 21 and 42. Supplementation with CB1 or CB3 decreased (p<0.05) the population of cecal Escherichia coli (E. coli) compared with the control on day 21. Birds fed C. butyricum diet had higher (p<0.05) population of cecal Bifidobacterium on day 21 and birds fed CB2 diet had higher (p<0.05) cecal Bifidobacterium on day 42 compared with the control birds. Supplementation with CB1 or CB2 increased (p<0.05) the number of cecal Lactobacillus on day 21 and supplementation with CB2 increased (p<0.05) Lactobacillus on day 42 compared with the control or antibiotic groups. The results indicate that supplementation with C. butyricum promotes growth performance, modulates nitrogen metabolism improves intestinal morphology and balances cecal microflora in broiler chickens.