Single and Combined Effects of and on Growth Indices, Intestinal Health, and Immunity of Broilers.

A total of 120 1-day-old commercial Cobb chicks were used to study the effects of () and/or () on growth performance, intestinal health, and immune status in broilers. The experimental groups were as follows: G1; basal diet (BD), G2; basal diet (BD) plus preparation at 0.5 g/kg diet, G3; BD plus preparation at 0.5 g/kg diet, G4; BD plus 0.25 g/kg preparation plus 0.25 g/kg . Results showed that the total body weight gain, feed conversion efficiency, and protein efficiency ratio were significantly higher ( < 0.05) in the G4 group than in the other groups. The mortality percentage was reduced in the probiotic-supplemented groups. The villi height was elongated, and the villus height/crypt depth ratio was significantly increased in G2 and G4 chicks, compared to those in the control. The crypt depth was significantly decreased in all the probiotic-supplemented groups. Hemagglutination inhibition titers for Newcastle disease virus (NDV) were markedly increased in G2 and G4 chicks at 35 days of age, compared to those in G3 and control chicks. These results showed that dietary supplementation of a combined mixture of and in an equal ratio (G4) was more effective in improving growth performance, immune status, and gut health of broilers, compared with individual supplementation at a full dose.