Effect of multi-strain probiotics on the performance of AA+ male broilers.

The aim of the experiment was to investigate the effects of a probiotic complex (PC) consisting of and on productive performance, carcass traits, immune organ indices, fecal microbiota counts and noxious gas emissions in AA+ male broilers. Three hundred and sixty 1-day-old AA+ male broilers with similar body weight (44.77 ± 0.25) were randomly divided into 3 treatment groups of 6 replicates each, with 20 broilers in each replicate. The experimental groups consisted of a group fed a basal diet and groups fed basal diet supplemented with 0.1 and 0.2% PC. The results showed that the addition of PC had no significant effect ( > 0.05) on growth performance, and carcass traits of AA+ broilers during the experimental period (1-42 days of age). Dietary addition of PC significantly increased the thymus index of AA+ broilers ( < 0.05), reduced the number of and in feces ( < 0.01) and reduced the concentrations of fecal NH and HS emissions ( < 0.01). Furthermore, birds fed 0.2% PC diet had the highest number of fecal counts. Results indicate that probiotic complex consisting of and enhances immune organ development, reduces the number of and in feces, increases the number of and reduces NH and HS emissions in feces. This trial provides a theoretical basis for the use of probiotic complexes in broiler production.