Effects of paraprobiotic as replacements for antibiotic on performance, immunity, gut health and carcass characteristics in broiler chickens

Abstract This study sought to determine the effects of dietary paraprobiotic (PPB) on broiler chicken performance, immunity, gut health, and carcass traits. 240 day-old CARIBRO Vishal commercial broiler chicks of identical body weight randomly divided into six treatment groups, each with five replicates and eight chicks in each replicate. Six dietary treatments were preapared: T1 = (control diet), T2 = T1 + 0.02 % (w/v) chlortetracycline (CTC), T3 = T1 + 0.2% (w/v) PPB, T4 = T1 + 0.4% (w/v) PPB, T5 = T1 + 0.6 % (w/v) PPB and T6 = T1 + 0.8 % (w/v) PPB, respectively. Body weight gain (BWG) significantly (P≤0.05) increased in the T5 (0.6 % PPB) and T6 (0.8% PPB) group. At the same time the feed intake significantly (P≤0.05) decreased and the feed conversion ratio (FCR) significantly (P≤0.05) improved in T5 and T6 group. There was a significant (P≤0.05) increase in cell-mediated immunity and haem-agglutination titre (HA titre) in the 0.6% and 0.8% PPB supplemented groups compare to the control group (T1). The percentage of carcass traits and organ weights did not significantly differ between the PPB-supplemented and control groups, but the percentage of live weight in cut up parts showed a significant improvement (P≤0.05) in the PPB-supplemented group. At 42 days, villus height, width, and crypt depth all significantly (P0.05) increased in the groups supplemented with 0.6 and 0.8% para-probiotics (T5 and T6). The results show that para-probiotics can be added to broiler diets at a rate of 0.6% (w/v) to enhance performance, immunity, gut health, and breast yield. The para-probiotic may therefore be a useful substitution for antibiotic growth promoters in the diet of chickens.