The synbiotic composed of Lactobacillus rhamnosus HN001, Pediococcus acidilactici MA18/5 M and Agave tequilana fructans can stimulate the bursa and the IgA production, increasing the size of its follicles and promoting the ability to resist infections caused by S. typhimurium in broilers. The gene discussed is CD79A; the disease is infection.