Effect of ZADO®, as enzymes from anaerobic bacterium, on extent of ruminal fermentation, nutrient digestibilities and average daily gain in steers

Abstract

Forty crossbred steers (Baladi x Friesian) were randomly assigned to two groups of twenty animals each. The average initial weight was 153.5 kg. The experiment lasted for 219 days. Two steers ftted with ruminal cannulas were used to take ruminal samples. The objectives were to evaluate the effects of exogenous enzyme supplementation (ZADO®) on nutrient digestibilities, ruminal ammonia and volatile fatty acids(VFA) and average daily gain (ADG). The enzyme mixture, which contained mainly xylanase , cellulase , protease and alpha amylase, was added to the concentrate to supply 40 g/ animal/day. The concentrate mixture contained 11% cracked corn, 8.5% agwa (minced date), 26.5% biscuits (bakery waste), 10% sugar cane molasses, 19% sesame cake, 2% soya bean meal ,6% beans, 14.2% rihan straw, 1% salt, 1% limestone and, 0.3 mixture of mineral and vitamins and 0.5% mineral mixture. Total digestibility of nutrients was significantly increased (p<0.01) by ZADO treatment vs control (dry matter, 61.7 vs. 69.1%; %; crude protein, 60.3 vs. 68.9%, neutral detergent fiber, 41.7 vs. 50.8%; acid detergent fiber, 32.2 vs. 40.8%)., ADG was 1.25 vs. 1.45 kg/d in control vs ZADO (p<0.05). VFA, (mM/100ml) was higher (p<.05) in the ZADO group in comparison with the control group (120 vs 110, respectively). Ammonianitrogen in the rumen (mg/N) was higher (p<0.05) in the ZADO group 65 vs 54 in the control group. Supplementing of steer diets with an enzyme mixture has the potential to enhance ADG and nutrient digestibility of fattening steers.