M. M. Hossain

Milk Urea Nitrogen of Dairy Cows: Milk Urea Nitrogen Concentration As a Tool to Monitor Dietary Protein Status of Dairy Cows M. M. Hossain

Feeding practices followed by farmers in different feed bases and seasons were based on rice straw, small quantities of green grasses from various sources with small supplementation of concentrates. Milk urea nitrogen (MUN) concentration was higher under good base (38.86 mg/dl) than poor feed base condition (28.55 mg/dl). MUN of the local and crossbred cow was found 31.97 and 35.44 mg/dl, respectively. Milk protein was positively correlated with milk yield. MUN increased linearly from 16.79 to 22.46 mg/dl as dietary rumen degradable protein was increased from the lowest (-25%RDP) to the highest (+25%RDP) levels. Urea concentration was 16.97 % higher in +25%RDP and 12.55 % lower in -25%RDP compared to control diet (19.20 mg/dl). The dietary CP and rumen degradable protein had positive impact on milk yield, milk composition and milk urea nitrogen. It was found that feeding dietary rumen degradable protein up to a level of 789 g/d had a significantly positive impact on MUN level, but diets having required level of rumen degradable protein for feeding dairy cows in local condition need to be confirmed through further research.