Tips for warming cold or frozen newborn calves

Any calf with a temperature below 37.7 C (100 F) needs assistance and warming. There are several ways to safely warm calves, and the methods you choose will generally depend on your facilities

calf and mother in winter

Precautions with Hot Water

The quickest way to thaw a frozen calf is with warm water, but if you use this method make sure the water is not too hot. If it’s very much above normal body temperature, it may damage the skin — which is already compromised if it’s been frostbitten. Rapid thaw at moderate temperature, 37 C to 40 C (100F to 105F) is best. Heat injury is always a risk if water is above 46 C (115F). Monitor rectal temperature to make sure you don’t overheat the calf. There have been some reports of extremely cold calves going into shock and dying when put into hot water. The sudden change may stop the heart.

If you warm a calf in a tub, make sure you completely dry him again before he goes back outside to cold temperatures. If he’s wet, he may chill again. Also make sure you don’t completely wash all the amniotic fluid off a newborn calf. If he’s perfectly clean and dry when you take him back to mama she may not recognize his smell and refuse to believe that it’s her calf!

Colostrum Substitutes

The best thing for a cold newborn calf is fresh colostrum. Next best is frozen colostrum, thawed and warmed to body temperature, or a commercial colostrum product. “There are big differences in quality, in the powdered commercial products, however,” says Dr. Dick Fredrickson, a veterinarian at Grandview, Idaho. “One product, called Calf Choice Total (CCT), made in Canada, is actual cow colostrum and it has a lot more absorbable antibodies in it than the products made from blood. It is sold under the brand name Headstart in Canada. It’s made from collected colostrum that’s gone through a screening test to check for diseases such as Johnes and others that might be passed through the cow into her colostrum,” says Fredrickson. CCT is an all-natural product, with nothing synthetic added.

If you don’t have any form of colostrum or milk available, an old ranch standby (using ingredients you’d usually find at a cow camp) is to mix a cup of warm coffee with some Karo syrup. “It won’t replace colostrum, but it will give the calf some warmth and energy. The caffeine in the coffee will stimulate his circulatory system to work better and the Karo syrup will give instant energy. If you have eggs available, mix in a couple of raw eggs. This will provide even more energy, and some protein,” says Fredrickson. He remembers giving this advice more than 40 years ago, and this emergency mixture has saved a number of calves.

Sometimes calves are born during severe storms or cold weather and become immediately chilled after birth. Any calf with a temperature below 37.7 C (100F) needs assistance and warming. There are several ways to safely warm calves, and the methods you choose will generally depend on your facilities and available choices.

Dr. Robert Callan at Colorado State University says that first and foremost the calf needs colostrum or milk for energy, so he can produce his own body heat. “Provide it by bottle or tube, whether it’s directly from the cow, warm milk replacer or homogenized milk. Feed at least a quart. If he’s too cold to suck, give it by tube,” he says.

The next step is to see what you can do to warm the calf externally. “There are two different thoughts about this. Some people like to use a warm water bath because it warms the calf’s extremities and body surface quickly, but this is hard to do out in a pasture far from the house or barn,” says Callan. Hot water warming is also labour intensive because you then have to get the calf completely dry afterward.

“What I like best, since it’s easier to do, is use a warming box. You need electricity, but a small ceramic electric heater in a small enclosed crate — where you can regulate the temperature — works very well. You are not only warming the cold body surface, but also the calf is breathing warm air into the lungs, which helps raise his core temperature. All his blood is going through his lungs, so if he can breathe warm air this really helps. Using a warming crate can be very beneficial for hypothermic calves,” says Callan.

Dr. James England at the University of Idaho says in many cases your first option might be to put a cold calf on the floor of your pickup with the heater running — if you find him out in a big pasture a long ways from the barn or an electricity source. “The main thing is to try to get him dried off and warm up his feet and legs. In many instances you don’t have hot water available to apply to cold limbs; I try to stick with warm air and getting the calf dry. If his feet are cold you know he is chilled, and you have to get the whole body warm.”

There are some nice calf-warming boxes you can buy (and the warm air comes from beneath the calf, helping warm and dry his legs and underside as well as the air he breathes), but you need electricity for these, and sometimes the calf is too far from an electricity source and all you have is your pickup. Breathing warm air, whether in a warming box or on the floor of your pickup next to the heater, can help warm a calf quickly.

He reiterates Callan’s warning about getting some warm milk into him — even if you have to tube him if he’s still too cold to suck a bottle. A cold calf only has about two hours’ worth of stored energy in terms of brown fat and what was left in the stomach from the amniotic fluid,” says England. When those stores are used up, he will be going downhill quickly in terms of being able to keep warm enough to sustain life in cold weather. If you can get energy into the calf he will warm up, able to generate more body heat. Colostrum is the best thing to feed him because it is easy to digest and contains twice the fat energy of regular milk

Callan recommends rechecking the calf’s temperature every few hours to make sure it is rising. “The energy provided with one feeding of colostrum or milk can be used up in four to six hours and the calf may need some more,” says Callan.

“The main thing is get the calf up off the snow if you can (onto some straw or something dry where the cow can lick him dry and take care of him), and dried off if he’s chilled already,” says England. “If he’s non-responsive I take him straight to the pickup. I’ve seen one rancher with a warming box on the front of his four-wheeler. He had a little 12-volt heater in it with warm air blowing on the calf while it’s being hauled to the barn.”

If you can get the calf indoors in a warm place, you can use warm water to help thaw out cold, freezing extremities (feet, ears, tail), but if the calf is still outdoors it’s counterproductive to use hot water. “You’re losing ground if you keep the calf wet, because it cools off so fast. You want to get him dry. Often it’s better to use warm, dry air and try to get some food into him,” says England.


If body tissues become too cold, ice crystals form inside the cell membranes and the cells rupture, killing the tissues. If it’s just superficial skin layers, they become discoloured and slough away (like a superficial burn peeling off). Damage to deeper layers and to small blood vessels near the surface may lead to more extensive tissue death.

When the legs, tail and ears are completely frozen, the calf may eventually lose his ears, or tail, or even his feet. Pricking the frozen extremity with a pin or needle (to see if there is any blood supply or any sensation/feeling in the tissues) can be a clue as to whether the tissue has a chance to return to proper function.

When the skin is frozen, it’s not advisable to rub the cold extremities too vigorously since this may further injure the damaged skin. If the tissue is not completely dead, the frozen area may swell as blood returns to the area, due to direct injury to the blood vessels and impairment of fluid moving in and out of the tissues.

“Hot water bottles wrapped in towels, or electric blankets, can also be helpful for a calf that’s just chilled but not frozen. I’ve seen some warming stalls that have electric blankets for the calves. A warm blanket, rubbing and stimulation, can help increase body circulation,” he says.

The problem may occur just because a calf didn’t get licked dry. Sometimes the cow couldn’t get up and lick it or didn’t have any interest in doing it, and the calf is still wet and getting colder. In some cases these calves may freeze to death. Some years the weather is so cold that even a well-mothered calf may freeze if the calf is born outdoors with no shelter. Your only hope for saving the calf is finding it in time to warm it up. Ears and tails may be frozen and eventually slough off, but you can save the calf if you can get his core body temperature back up to normal.

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