Investigation of probiotic and synbiotic effects of dietary inclusion of two dietary supplements on growth performance and immune responses of broiler chicks challenged with Salmonella Typhimurium

This study was conducted to investigate the synbiotic and probiotic effects of two dietary supplements produced by Iran Scientific and Industrial Research Organization on growth performance and immune responses of broiler chicks challenged with Salmonella Typhimurium. 360 Ross 308 broiler chicks were studied in 6 treatments with 6 replications and 10 broiler chicks per replicate. This study was conducted in a factorial arrangement based on completely randomized design with 2 factors of challenge (challenge and non-challenge) and additives (lack of additive, 0.2 g/kg dietary supplement). Probiotic was containing Bacillus subtilis, B. licheniformis, and Saccharomyces cerevisiae. Synbiotic was contained same bacteria and fructans. Growth performance, including average daily feed intake (ADFI), average daily gain (ADG), feed conversion ratio (FCR), production index, and immunoglobulins G and M were investigated. The results showed that challenge with Salmonella decreased ADFI, ADG and production index compared to non-challenged broiler chicks (P<0.001). Challenge decreased the levels of immunoglobulins G and M compared to non-challenged broiler chicks (P<0.001). However, the results showed that dietary inclusion of supplements increased production index, ADFI and ADG and immunity compared to non-treated broiler chicks (P<0.001). In conclusion, the use of 0.2 g/kg of dietary supplements produced by this organization improves growth performance and immune responses against infectious challenges in broiler chicks due to their probiotic and synbiotic properties.