The biting cold of winter reminds dairy farmers of the importance of protecting calves. Calves experience cold stress when the ambient temperature declines below their thermoneutral zone. That’s generally between 55 degrees and 70 degrees Fahrenheit. A calf’s maintenance requirement increases by one percent for each degree beneath the thermoneutral zone. Here are seven ways to ease the effects of cold stress.
- Dry calving area. Calves are born with two percent of their bodyweight as brown fat. It's a potent energy source that can provide 40 percent of the calf’s ability to thermo-regulate in cold and wet environments. Calves should be born in a clean and dry calving area. They should be dried as soon as possible after birth so their store of fat isn’t burned within hours.
- Whole colostrum. Whole colostrum contains colostral fat, nature’s key to unlocking brown-fat synthesis. In cold weather colostral fat will jumpstart brown fat to start providing heat. It’s also critical to provide the calf at least 150 grams of immunoglobulin G within a couple hours of birth. That provides passive immunity to the calf. If needed a 100-percent whole bovine dried-colostrum replacer should be used.
- Calf Coats. Calf coats can provide calves an essential extra layer of insulation. Calves should be thoroughly dried before a clean calf coat is placed on them.
- Bedding. No matter what time of year, calf bedding should be kept dry and clean. It’s especially important in cold weather. There should be adequate bedding to cover a calf’s feet and legs when it is laying down.
- Nutrition. Calves should be fed more calories in cold weather to provide the extra calories needed to help maintain body temperature and growth needs. Dairy farmers can achieve this by either increasing the fat content or total solids content of their milk or milk replacer. Or they can add a third feeding. Milk or milk replacer also should be fed as close to body temperature as possible – 105 degrees Fahrenheit is a good target.
- Starter Intake. Calves should be offered starter as soon as day 2 or day 3. The sooner a calf begins consuming starter the sooner it will begin to ruminate and generate more internal heat. Some direct-fed microbial products include probiotics and fatty-acid blends that can stimulate starter intake and rumen development.
- Dehydration. Dehydration can be as much a problem in the dead of winter as it is in the heat of summer. Warm water should be offered immediately after each calf feeding. Maintenance levels of calf electrolyte can be fed to combat dehydration.
By making nutritional and managerial adjustments, dairy farmers can help calves better face the bitter cold of winter and give them their best chance of thriving. Visit genex.coop/herd-care-line for more information.