Effect of exogenous fibrolytic enzymes on the productive performance of lactating sahiwal cows

The study was conducted to assess the effect of supplementing a mixture of cellulase and xylanase (1:1) @ 1.5 or 3.0 g/kg DM on in-vitro digestibility of diet containing wheat straw, concentrate mixture and green fodder in 40:40:20 ratio. IVDMD, IYOMD, IVNDFD and TVFA concentration were higher (P<0.05) at E_1.5 and E_3.0 levels, both at 24h and 48h post-incubation, but no significant difference was observed between E_1.5 and E_3.0. Acetate concentration was higher (P<0.05) at E_3.0 level as compared to E₀ at 24h post-incubation while at 48h post-incubation, it was higher (P<0.05) at both E_1.5 and E_3.0 levels as compared to E₀. Lactating Sahiwal cows (12; 8.73±1.42 kg milk/d; 60.09±5.50 days in milk in 2.09±0.01 lactation) divided into two groups were offered either control TMR or TMR supplemented with 1.5 g EFE mixture/kg DM. There was no effect on CP intake in the two groups whereas, DM and TDN intake were higher (P<0.01) in treatment group over that of control. Average daily milk yield and 4% FCM yield increased (P<0.05) by 7.66 percent and 8.58 percent respectively, in the treatment group over that of control, without any effect on the milk composition. The digestibility coefficients of CF and NDF were higher (P<0.05) by 8.24 and 7.49 percent respectively, in the treatment group over that of control, though there was no effect on feed conversion efficiency for milk production. The results indicated that supplementation of cellulase and xylanase mixture (50:50 w/w) at 1.5g/kg DM of the TMR significantly increased (P<0.05) average daily milk and FCM yield in Sahiwal cows.