Improving nitrogen use efficiency of dairy cows in relation to urea in milk – a review
2016
Guliński,Piotr | Salamończyk,Ewa | Młynek,Krzysztof
未知. The main reason for elevated levels of urea in milk is connected with excess protein contents in feed rations, and energy and protein imbalance. The increase in the percentage of total protein from 13% to 18% DM per ration is accompanied by an increase in the urea level by about 80 mg to over 150 mg in 1 liter of milk. Additional factors affecting the level of urea in milk include the following: frequency of feed administration, number of milkings and length of the interval between milkings, cow’s body weight, water intake volume, the level of Na and K ration supplementation, as well as rumen pH. Recent research indicated that an addition of natural plant-origin biologically active compounds, such as tannins, saponins and essential oils, reduce ammonia production and finally urea content in milk. Information on the concentrations of milk urea and nitrogen in dairy cows allows to assess energy balance and protein rations supplied, which in turn can help to reduce both feed costs and nitrogen emission (N) to the environment.
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