Research On Animal Production

   The NorFor is a semi-mechanistic system, which predicts nutrient supply and requirements for maintenance, milk production, growth and pregnancy in catlle. This research aimed to evaluate the effects of grinding, pelleting and steam-flaking of corn grain on protein characteristic using NorFor model according to a completely randomized design. Degradability of dry matter and protein of the processed corn were determined at 0, 2,4,8,16,24 and 48 hours after feeding with technique of nylon bags using three mature rams of Zel breed. By using the data gathered from the measurement of ruminal degradability of crude protein of corn, including soluble crude protein (sCP), potentially degradable crude protein (pdCP), degradation rate of potentially degradable crude protein (kdCP), indigestible crude protein (iCP) in feedstuff was estimated in NorFor system it was shown that effective degradability (%) of dry matter and protein steam-flaking of corn grain was higher than grinding, pelleting. Also, the slow fraction of grinding of corn grain was higher, both in dry matter and protein degradation. Corn steam-flaking increased soluble protein (sCP) and total soluble protein (sCP+ pdCP) and potential degradation protein, and reduce the kdCP, comparing with corn pletting (397 in contrast of 816) was significantly different (P<0.0 .(In this sdtudy, indigestibility of crude protein (iCP) was very low. The overall findings of this study indicated that increased rumen degradability of dry matter and protein as well as the total soluble protein (sCP+ pdCP) steam-flaking of corn grain was high.