Effects of supplementation of β-glucan on the growth performance and immunity in broilers

Two experiments were conducted to evaluate the efficacy of β-glucan on commercial broilers. In experiment 1, one hundred and forty-four broiler chicks were employed in a 2 × 3 factorial design with cage and open floor housing with three levels of β-glucan viz. 0%, 0.02% and 0.04%. In experiment 2, ninety-six broilers were used with 4 treatments: No β-glucan and antibiotic (T1), β-glucan 0.03% (T2), antibiotic (T3), and β-glucan 0.03% + antibiotic (T4) for 34 d with 3 replicates of 8 chicks each in both studies. During experiment 1 there was no significant effect of the feeding system or the β-glucan levels on the performance from 0 to 17 d but during 18–34 days birds housed on the open floor had significantly (p < 0.0001) higher weight gain compared with those in cages. In experiment 2, no significant effect was noticed on the weight gains when the effect of β-glucan, antibiotic or their interaction were tested. The retention of dry matter increased in both experiments with β-glucan supplementation. The CD8 and TCR 1 cells were significantly higher in the 0.04% β-glucan group at 42 days as compared with the control. It could be concluded that β-glucan supplementation was beneficial for broilers.