Effects of adding different levels of Iranian native synbiotic to drinking water on performance, carcass characteristics and small intestinal microbial population of broiler chickens

This study was conducted to evaluate the effects of adding different levels of a domestically produced synbiotic to drinking water on production traits, carcass characteristics and the small intestinal microbial population of broiler chickens. Four hundred one-day-old Ross 308 broilers (a mixture of two sexes with equal proportion) were used in a completely randomized design with 4 treatments, 5 replicates, and of 20 birds per each replicate. Experimental treatments included adding levels: zero (control), 50, 100 and 150 g of synbiotic (Biopoul) per 1000 liters of drinking water. At 42 days of age, the addition of 50 or 100 g of synbiotic per 1000 liters of drinking water significantly decreased feed conversion ratio (P < 0.05). The increase of production index in the group receiving 100 g of Biopoul compared to the control showed a tendency (P = 0.08). Biopoul in the levels of 50, 100 and 150 g increased the total number of lactobacilli and decreased the number of yeasts and molds, coliforms and total gram-negative bacteria in the ileum compared to the control (P<0.05). According to the obtained results, the use of 100 g of synbiotic Biopoul per 1000 liters of drinking water of broiler chickens can improve the production index while helping to balance the small intestinal microbial population.