Hypothermia is a profound drop in body temperature.
"Animals less than 48 hours old or animals with a pre-existing condition or disease are at the greatest risk for developing hypothermia," says Charlie Stoltenow, North Dakota State University Extension Service veterinarian.
Newborns are susceptible because they often are hypoglycemic, which means they have low energy reserves and electrolyte imbalances. Animals with pre-existing conditions, such as pneumonia or old age, are susceptible because they have impaired body reserves and may succumb to very cold and windy conditions more easily.
Frostbite is the destruction of tissue in a localized area due to extreme cold. It is uncommon in healthy, well-fed and sheltered animals, but animals that are less than 48 hours old or have a pre-existing condition run the greatest risk of developing frostbite.
The areas most likely to be injured include the ears, tail, teats, scrotum and lower parts of the limbs, especially the hooves. Hind limbs are more likely to be affected in cattle since their normal posture is to draw their front legs under their chest while their hind legs protrude from under their body.
"Treating cases of hypothermia and frostbite is often unrewarding," Stoltenow says. "Prevention is of primary importance."
Prevention consists of:
·Keeping the animals, especially newborns, warm and dry: Provide windbreaks to counteract the effects of the wind chill.
·Making sure animals have adequate bedding: Bedding insulates he animal from the snow and ice underneath the body and lowers the animal's nutritional requirements. Bedding allows the animal to "snuggle" into it and lowers the body surface area exposed to the wind.
·Increasing the amount of energy supplied in the animal's diet
Stoltenow has this advice for producers with livestock suffering from hypothermia or frostbite:
·Warm calves with hypothermia slowly. The heat source should be about 105 to 108 degrees Fahrenheit. Warmer temperatures may cause skin burns or shock. Sources of heat include a warm-water bath, electric blanket, heat lamps or hot- water bottles, and a warming box.
·Provide calves with an energy source. Feed colostrum to newborn calves within the first six to 12 hours of life. Provide milk or electrolytes with an energy source such as glucose. An esophageal feeding tube works well to supply these energy sources. Without fluids, the animal becomes acidotic as it warms. An acidotic calf is predisposed to contracting scours or pneumonia.
·Warm areas suffering from frostbite quickly. Frostbite is the destruction of tissue. To prevent permanent damage, restore circulation in the affected areas as soon as possible. The heat source should be about 105 to 108 F. However, do not rub affected areas. They already are damaged and quite fragile. As the area warms, it will be painful. Do not let the animal rub these areas; that will make the situation worse. In severe cases, animals may need painkillers. Consult your veterinarian.
Frostbite in teats and scrotums could be a problem as well. However, frostbitten teats may be difficult to detect. The first sign may be a thin calf. The teat end is affected and can slough. If this happens, the sphincter muscle of the teat may be lost. This makes mastitis a possibility.
Also, frostbite may cause an affected teat to dry up because the cow won't let the calf nurse. In addition, the frostbitten teat may go unnoticed until next year. At that time, the calf is thin, and when the cow is examined, the teat is healed over with scar tissue. This teat will need to be opened, Stoltenow says.
Bulls' scrotums and testicles can suffer frostbite, too. Often these lesions go unnoticed. They can cause temporary or permanent infertility. All herd bulls should have breeding soundness exams 45 to 60 days after the last severe cold spell. Your veterinarian can help you with these exams.