This greater persistency means that the heifer cannot route as high a proportion of energy intake as can her older herdmates toward the replenishment of body fat stores. These cattle must gain 50 to 75 kilograms during each of the first two lactations to reach mature body weights. To ensure that the additional nutrients needed for growth are provided, the standard recommendation has been to feed more concentrates to these cattle. Today's genetically superior cattle can produce large volumes of milk, even during their first lactation. With the mature lactation curve, typical of second lactations, adequate tissue energy reserves are critical to achieving desirable peak milk yields as well as satisfactory butterfat synthesis.
Body size is a major factor influencing dry matter intake.
Lack of sufficient growth will limit the improvement in feed intake needed to support higher milk yields. As a result of inadequate management the genetically superior heifer could demonstrate poor second lactation performance or burn-out, and may be wrongly culled. Correct management of energy balance throughout the lactation and reproduction cycles of the dairy cow can significantly improve her capacity to generate profit. This information is provided as a public service, but we cannot guarantee that the information is current or accurate. Readers should verify the information before acting on it.