Effects of Probiotics on Growth and Immunity of Piglets.

Growth promoting antibiotics are used in modern animal husbandry to promote growth and avoid infections. Negative effects of these antibiotics on human health are a big concern and they need to be replaced. Probiotics are expected to be a good replacement for growth promoting antibiotics. In this study, we evaluated effects of probiotics on growth and immune status of liver and secondary lymphoid organs of piglets. Body weights of probiotic-fed piglets were heavier than those of control piglets (p < 0.05) at days 30 and 45 of the experiment. Relative populations of CD4+ and IgM+ cells isolated from the liver were significantly increased (p < 0.05 and p < 0.01, respectively) in probiotic-fed piglets compared to control piglets. CD4+CD8+ T cells were significantly decreased (p < 0.05) in jejunal Peyer’s patches of treated piglets. Phagocytosis of MHC class II+ cells isolated from the liver of probiotic-fed piglets was significantly higher (p < 0.05) than that of control piglets. Phagocytosis of granulocytes isolated from the liver and peripheral blood of probiotic-fed piglets were also higher than those of control piglets. These results indicate excellent effects on growth and immune status of piglets. In conclusion, probiotics have beneficial effects on the growth and health of piglets and could be good replacement for growth promoting antibiotics.