INFLUENCE OF SUPPLEMENTALSHEEP RATION WITH ZINC SOURCE (INORGANIC VS. ORGANIC) ON THEIR DIGESTIBILITY AND RUMINAL FERMENTATION.

This study was conducted to investigate the influence of zinc sulfate and zinc methionine supplementation on the nutrients digestibility, nutritive values of feeds and ruminal fermentation of sheep. Fifteen sheep averaged  (52.2 ± 1.40 kg)were divided into five similar groups (three animals each),they were fed basal diet containing 33.34 mg Zn/kg dry matter (DM) with no supplemental Zn (control). Control group was consulted of concentrate feed mixture (CFM), corn silage and rice straw without zinc supplementation. The other four experimental groups supplemental with 30 or 60 mg of Zn/kg of DM from Zn sulfate (ZnS) or zinc methionine (ZnMet) to control diet. Results indicated that zinc addition either as zinc sulfate or zinc methionine increased (P<0.05) the digestibility of all nutrients which were reflected on the nutritive values (as TDN and DCP) of diets. Addition of zinc sulfate or zinc methionine reduced ammonia-N and increased both TVFA's rumen volume, rumen digesta and microbial protein synthesis of sheep.