Feed provides the nutrients that are the precursors, either directly or indirectly, of the principal milk solids. Thus, an increase in feed intake usually results in the production of a greater volume of milk. In general, the proportional increases in fat, protein and lactose yields are approximately the same as the proportional increase in milk volume. Milk composition changes little.

It is critical to maximize feed intake of cattle so that negative energy balance is minimized during early lactation. As cows consume more energy than they use, body weight is regained, losses in body condition are minimized and cows produce milk of normal fat and protein content. Increasing feed intake, and the resulting overall increase in energy, can increase milk protein content by 0.2 to 0.3 percent.

High-producing cows should eat 3.5 to 4.0 percent of their body weight daily as dry matter. If a herd is consuming less than this, production of solidscorrected milk may be limited. Major factors that can affect feed intake include:

• Feed bunk management (keep feed bunks clean, not empty)

• Feeding frequency

• Feed sequencing

• Ration moisture between 25 and 50 percent (to optimize dry matter intake)

• Social interactions and grouping strategy of the herd

• Abrupt ration changes

• Physical facilities

• Environmental temperature

Increased feeding frequency of lowfiber, highgrain diets increases milk fat levels. The greatest increase occurs in diets of less than 45 percent forage and when grain is fed separately as in parlor feeding. When diets are fed as a total mixed ration, feeding frequency becomes less important as long as the feed remains palatable and is fed and mixed a minimum of once a day. During hot weather, more frequent feeding helps keep feed fresh and palatable