Pejman. Atrian and Habib. Aghdam Shahryar
To examine the effect of fibrolytic enzymes on performance in feedlot cattle, 20 feedlot cattle with average 250± 20 Kg live weight were used in a completely randomized design with 4 treatment and 5 replicates in 21-d periods. Cattle were fed balanced TMR including %30 alfalfa hay and %70 Concentrate on DM basis and 9.5, 14.25 and 19 ml of fibrolytic enzyme were used per 10 Kg of alfalfa hay. Using moderate level of enzyme (14.25ml/10Kg alfalfa) increased ADG and DMI 23.1 and 4.3 percent respectively compared to control. Dry matter intake also significantly increased (p<0.05) in 2nd and 3rd treatments (9.5 and 14.25 ml enzyme) comparing to control group. Feed conversion improved significantly (p<0.05) in treatments, containing 14.25 ml enzyme compared to other treatments. Results of this study showed that using 14.25 ml of fibrolytic enzyme per 10 Kg alfalfa hay were most effective in terms of improving daily gain and dry matter intake. Also it was indicated that level of applying had a certain limit and high level of enzyme (19ml/10Kg hay), decreased feed conversion and average daily gain.