The influence of fungal β-glucan on nonspecific immunity in broiler chicks

The influence of β-1,3/1,6-D-glucan isolated from Pleurotus ostreatus added to the diet at a level of 20 g/t (group B20) and 40 g/t (group B40) for the whole trial and 40 g/t from the 1st to the 14th day and 20 g/t from the 15th to the 42nd day of the trial (group B40+20) was examined on some immune markers in hybrid Ross 308 chicks. A significantly higher number of monocytes (p<0.01, p<0.05) and significantly higher phagocytic indiced of leukocytes (p<0.01) and heterophiles (p<0.001) after 35 days of the trial were observed in group B40 in comparison to the control group and group B20. Significantly higher phagocytic indices of leukocytes (p<0.01) and heterophiles (p<0.001) in comparison to the control group and group B20 was found also in group B40+20. The total number of leukocytes, heterophiles, eosinophiles, basophiles and lymphocytes were not significantly influenced, but heterophil/ lymphocyte ratio was significantly lower in group B40 (p<0.05) in comparison to the control group. These results show that β-glucan from Pleurotus ostreatus can stimulate nonspecific immunity and reduce the susceptibility of stress in broiler chicken, whereas higher concentrations have a stronger effect.