The enzyme β-glucanase was extracted from Trichoderma reesei in bovine rumen fluid samples collected from a slaughterhouse and its effect was investigated in broilers. Data collected was broiler performance, carcass characteristics, duodenum microbial flora, hematological, and immunological parameters. β-glucanase activity was assayed through spectrometry and was approximately 0.434 IU per gram culture medium. In the current study, endoglucanase enzymes were extracted from Trichoderma reesei. A total of 160 local broilers (Golpayegan-Ross hybrid) were allocated to 4 treatments with 4 replicates per treatment. Over a 49-day experimental period, broilers were fed a basal diet (T1), basal diet plus 20% barley (T2), basal diet with 10 IU extracted β-glucanase and 20% barley (T3), and basal diet with 10 IU commercial β-glucanase and 20% barley (T4). The T3 treatment resulted in the greatest body weight gain at the end of experiment (P < 0.01). No significant differences were for feed conversion (FCR; P > 0.05). The highest cholesterol, high density lipoprotein (HDL), low density lipoprotein (LDL), and LDL cholesterol ratio was observed in the T3 treatment. The highest concentrations of immunoglobulin G1 (IgG1), immunoglobulin G2 (IgG2), and immunoglobulin M1 (IgM1) were observed in the T4 treatment. The T3 treatment resulted in the best response for all measured carcass characteristics. The highest levels of aerobic bacteria, lactobacilli, anaerobic bacteria, and E. coli were associated with the T4, T3, T4, and T1 treatments, respectively. It is concluded that β-glucanase supplementation can be used to overcome the anti-nutritive effects of water soluble barley non-starch polysaccharides (NSPs) and consequently enhance broiler performance without any adverse effects on humoral immunity parameters.
