The Relationship of Milk Urea Nitrogen to Urine Nitrogen Excretion in Holstein and Jersey Cows

摘要

The objectives of this study were to assess the rela - tionship between urinary nitrogen excretion (UN, g/d) and milk urea nitrogen concentration (MUN, mg/dl) and whether the types of carbohydrates fed interacts with the dietary CP and the breed (size) of cows to affect this relationship. Eight multiparous cows (four Holstein and four Jersey) were fed four different diets In a 2 × 2 factorial arrangement of levels of crude protein (13 and 17/100) and levels of neutral detergent fiber (30 and 40/100). The experimental design was a split plot Latin square with breeds forming the main plots and Diets forming the subplots.