Effects of metabolizable protein supply on N efficiency: plasma amino acid concentrations in dairy cows

摘要

Efficiency of N utilization improves with low N intake but this practice remains a viable option only if milk production is not compromised. With this strategy in mind, we studied in a broader perspective the effect of reducing metabolizable protein (MP) supply on urea kinetics, endogenous N secretions, milk yield, N efficiency and plasma amino acid (AA) concentrations. This manuscript reports the three latter.