The' objective of this paper is to examine the role of exogenous fibrolytic enzymes on ruminant productivity. These
fibrolytic enzymes have been reported to be effective to increase feed efficiency and ruminant performance. The
response of these enzymes is dependent on experimental conditions and is variable. This variation was due to
experimental conditions such as the activities and characteristics of the enzymes supplied, variability in enzyme
activity, method of providing the enzyme product to the animal and enzyme level in the feed. A limited number of
ruminant enzyme products is now commercially available, and this list of products is expected to grow. Random
addition of enzymes to diets without consideration for specific situations and substrate targets may disturb or
delay the efficiency of enzymes and adoption of enzyme technology on farms.
