Synbiotic consumption can modulate immune response. This work involves studying the effect of a synbiotic on lymphoid organs and IgA of broilers infected with Salmonella typhimurium and Clostridium perfringens. A total of 258 one-day-old male broilers (Gallus gallus domesticus), line COBBAvian48 (free of growth-promoting antibiotics), were distributed into eight treatment groups. A symbiotic mix comprising Lactobacillus rhamnosus HN001 and Pediococcus acidilactici MA18/5 M as probiotics and 4.5% (0.045 g g-1) of Agave tequilana fructans as prebiotic per dose (one milliliter) was administered through drinking water the first day of life. Bursa, spleen and thymus were analyzed. Broilers treated with the synbiotic, whether or not infected with pathogens, had bigger bursa follicles than the non-treated (p < 0.05), and the ones from the synbiotic group had more lymphocytes than the control group (p < 0.05). Thymus follicles of the synbiotic group were bigger than the control group (p < 0.05). Lesions associated with Salmonella infection were found in the bursa, however, in the broilers treated with the synbiotic, the lesions were less intense and were not present after 32 days of life. The synbiotic mix can stimulate the bursa, increasing the size of their follicles and promoting the ability to resist infections caused by S. typhimurium in broilers.
Keywords: Clostridium perfringens; Salmonella typhimurium; bursa; prebiotic; probiotic; spleen; thymus.