Posted by Dr. Steve Dudley on June 16 2005 10:56
Dairy Calf Newsletter 4th Quarter 2005
As we enter the cooler half of the year, attention needs to be placed on maximizing calf health and growth especially in calves that are eight weeks of age and younger. This article will highlight what can be done nutritionally and environmentally to support the calf during the cooler winter months.
Nutrition
The ideal temperature for calves is 50 degrees. As the outdoor temperature drops, the calf needs to use more energy to maintain normal body function and body temperature. With the increased need for energy to maintain normal body processes, there is a decrease in the amount of energy and nutrients available for immune system function as well as growth. When the temperature drops below 20 degrees, calves that are on a traditional 20/20 milk replacer program go into a negative energy balance. At 20 degrees, the energy it takes for the calf to maintain itself is approximately equal to what its getting with two quarts of a 20/20 milk replacer twice a day. As the temperature goes below 20 degrees, the calf is actually using more energy than its consuming through the milk replacer. The extra calories needed will either come by the calf reducing its own fat stores, which are fairly limited in a young calf, or by increased starter feed consumption.
Increased starter feed consumption is not an issue in older calves but calves in the first two weeks of life generally do not consume enough starter to offset the negative energy balance. The bottom line is that if the temperature gets below 20 degrees and a 20/20 milk replacer is fed, calves will actually lose weight. If they are eating some starter feed, they may just maintain their weight or gain possibly a half of a pound per day.
We would like to see an average daily gain of calves from birth until weaning at 0.9—1.0 pounds per day. This is achievable, even in the winter months with proper nutritional management as well as environmental management. There are several options for increasing the calories that calves receive when the temperature drops below 20 degrees.
Increase caloric consumption:
Feed 1.25 pounds of milk replacer per day instead of 1 pound of milk replacer. This is an option if you’re doing twice a day feeding. Make sure you increase the volume of water so that the concentration of the milk replacer doesn’t change, because if it becomes more concentrated, this can cause scours because of the milk replacer being too strong.