Low Temperatures and Negative Energy Balance in Calves
– Don Sockett and Melissa Behr, WVDL; Tom Earleywine, Land O’Lakes
The WVDL is seeing an exceptional number of dairy calves (≤ 6 weeks of age) with no white fat in the coronary groove of the heart, mesentery, and perirenal tissues which is consistent with the calves not receiving enough feed. This problem usually begins in January or February, but emaciated calves began showing up at WVDL in late November 2013. Many of these calves had a prior illness such as calf scours. Demand for nutrients increases during illness; in particular the demand increases for protein, energy and fat-soluble vitamins. These nutrients are needed for maintenance, tissue repair, immune function, and to provide body heat. Optimizing nutrition of sick calves can make the difference between a dead and a healthy calf.
When the ambient temperature drops to 15 °F, feeding 3 quarts of milk (12.5% total solids) or its equivalent in milk replacer (MR) twice a day will provide an 88 lb. calf with enough nutrition for 0.5-0.75 lbs/hd/day of growth. However, if the calf is stressed further (draft, wet or dirty hair coat, develops scours, pneumonia etc.) there is insufficient energy and protein in the diet to meet the needs of the calf and it will begin losing weight. Since calves are born with only 3-4% of body weight as fat, they can become emaciated and die if energy balance is negative for > 3-5 days. Since calf scours is a common problem on US dairy operations, winter feeding programs should be formulated to take into account the increased protein and energy demands caused by calf scours. Also, calves should be provided with a jacket and kept in a dry, draft-free environment that is bedded with straw that is deep enough to cover its legs when lying down. Calves should be offered a highly palatable calf starter that is high in protein (18-22%) and energy beginning at 2-3 days of age, and have access to free-choice warm water within 30 minutes of being fed milk or MR.
Winter Feeding Program
Since ruminants do not metabolize fat as efficiently as non-ruminants, just providing more fat in the diet is the least satisfactory way of providing additional nutrition to the calf. The diet must have enough energy and protein so the calf can have efficient, lean growth, adequate immune function, and healing of damaged tissue caused by events like scours or pneumonia.
The dairy producer has 3 options available:
- Continue to feed the calves 3 quarts of milk or MR twice a day but increase the total solids content from 12.5 to 15%. To avoid problems, producers need to work closely with their dairy calf nutritionist if they choose this option.
- Continue feeding the calves twice a day but increase the volume of milk or MR fed per feeding from 3 to 4 quarts.
- Feed the calves 3 quarts of milk or MR three times a day instead of twice a day. There should be at least a 13-14 hour interval between the first and third feeding. This is the best option because calves do better when they are fed three times a day instead of twice a day.