The effect of dried corn steep liquor and LactoFeed® probiotics on performance, intestinal microbial population and humoral immune response of broilers

The effect of dried corn steep liquor (DCSL) and probiotics on growth performance, intestinal microbial population and humoral immune response of broilers using 320 one-day-old Ross 308 broilers in a 2 × 4 factorial arrangement experiment with four DCSL levels (zero, two, four and six percent) and two levels of probiotic LactoFeed® (zero and 150 mg/kg) were evaluated in a completely randomized design with eight treatments, four replicates and 10 birds per replication for 42 days. Body weight gain, feed intake, feed conversion ratio, lactic acid and coliform bacterial populations, as well as the response of broiler chickens' humoral immune system against Newcastle disease, bronchitis and influenza viruses were measured. In the grower, finisher and whole period effect of LactoFeed probiotics and DCSL and their interaction on body weight gain and feed conversion ratio were not significantly different. In the starter period, birds fed diets containing four percent DCSL consumed more feed and gained more weight than chickens fed diet without DCSL (P<0.05). Interaction of six percent DCSL and probiotic increased feed intake in the starter period compared to diet lacking these compounds (P<0.05). The greatest antibody titer against Newcastle disease, influenza and bronchitis viruses was observed at six percent of DCSL (P<0.05). The interaction of DCSL and probiotics decreased the population of coliforms and increased the population of lactic acid bacteria (P<0.05). According to the results of this study, the use of DCSL and probiotics in the diet of broilers improves the humoral immune response and intestinal microbial population.