Effect of Supplementing Slow Release Nitrogen Product on the Lactation Performance of Dairy Cows

Abstract

A study was undertaken to evaluate the effect of feeding slow-release nitrogen product (SRNP) on the lactation performance of crossbred dairy cows. Eight crossbred cows in mid-late lactation were used in a Youden Latin square design. Treatment diets were T1 containing 2% urea in the concentrate portion of diet, and T2 and T3 diets containing 2 and 4 percent of SRNP, replacing urea on iso-nitrogen and iso-soluble nitrogen basis. The SRNP used in the study was a polymer coated urea compound containing 42% total N with 52.1% soluble N. The diet of the experimental cows comprised corn silage and finger millet straw as roughage source and a compounded feed mixture. There were no differences (P>0.05) in DM intake, milk yield (both total and 4%fat FCM) or milk constituents of cows among the treatment groups. A similar (P>0.05) digestibility of nutrients in the diets of three experimental groups indicated that the supplementation of SRNP had no influence on the utilization of nutrients in the lactating dairy cows. In the current feeding management system, comprising of corn silage, finger millet straw and a compounded feed mixturein the diet of dairy cows, feeding SRNP to replace urea on isonitrogenbasis was found not advantageous. It is concluded that the slow-release nitrogen product used in the present study can replace urea in the diet of lactating dairy cowswithout affecting their performance.