Energy requirements
Energy requirements of dairy cows differ from the maintenance requirements needed to maintain the vital body functions and the requirements necessary for production in order to obtain milk with corresponding quantity and quality.
Establishing the energy requirements for maintenance is based on the body weight of the animals:
UFL/day = 1.4 + 0.006 x LW (kg)
Establishing the necessary energy for milk production is made by taking into account the amount of milk, the milk protein content, fat and lactose, as well as the use randament of the energy in milk production.
UFL = MP x 0.44
where: MP = daily milk production of the cow (l).
Depending on the fat percentage from milk, the energy demand for producing a liter of milk with 4% fat is of 0.44 UFL.
To reconstitute the body reserves, it is advisable to ensure energy supplement of 4.5 UFL/kg increase in weight.
During the period in which the lactation overlaps with the first 7 months of pregnancy, the required energy determined for milk production meets the requirements for developing the fetus.
Between two periods of lactation, it is recommended that cows are given a breast rest period that lasts for about two months, during which the cow's organism is to recover in order to achieve a maximum production of milk in lactating which will follow and moreover to ensure optimal conditions for an optimum calving and for achieving a healthy calf. As a result, the eighth month of gestation, the necessary computed energy for maintenance will be increased with 1.6 UFL / head, while the ninth month with 2.6 UFL/head. For cows with high milk production, the energy supplement can be assured, starting with the seventh month (0.9 UFL/head).
