Comparative effects of probiotic, prebiotic and synbiotic supplements on performance, jejunal morphology, serum lipid profile and antibody response of broiler chicks

A 42-d trial was conducted to compare the effects of probiotic, prebiotic and synbiotic supplements on growth performance, morphology of the jejunum, serum lipid profile and antibody response of broiler chickens. A total of 400 one-d-old male broiler chicks were randomly divided into four treatment groups of four replicates (25 birds per replicate) and fed corn-soybean meal diets. The dietary treatments consisted of a basal diet without any feed additive (control diet), a basal diet with added probiotics (diet Pro), a basal diet with added prebiotics (diet Pre), and a basal diet with added synbiotics (diet Syn). The birds fed diet Syn exhibited higher body weight gain (BWG) and better feed conversion ratio (FCR) than those fed the control diet during the entire experimental period (P < 0.05). Feeding diets Pro, Pre and Syn significantly increased the villus height and villus height:crypt length ratio in the jejunum of broilers at 42 d of age (P < 0.05). The birds fed any of the experimental diets, exhibited lower levels of serum total cholesterol and low-density lipoprotein cholesterol (LDL-C) than those fed the control diet at 28 and 42 days of age (P < 0.05). At 41 d of age, the total antibody titer against sheep red blood cell (SRBC) in the birds fed diets Pro, Pre and Syn were higher than in the birds fed the control diet, with the birds fed diet Syn having the highest antibody titer (P < 0.05). None of the diets affected feed intake, crypt depth in the jejunum, serum triglyceride level and primary antibody response against SRBC. The results suggested that diets supplemented with probiotics, prebiotics and synbiotics could improve growth performance and health benefits of the broiler chicks by improving intestinal morphology, fat metabolism and immune function.