Despite the warm temperatures we've experienced this winter, we still have experienced our share of cold snaps. When those frigid stretches of winter coincide with calving time, completely new sets of problems present themselves for the cow-calf producer striving to get calves off to a good start.
Frostbite is one of those problems. Newborn calves and those suffering an illness are most susceptible to frostbite in extremely cold weather. It's the extremities the tips of the ears, the tail, and the rear feet (since calves usually tuck their front feet under their body when lying down) that are most commonly affected. Freezing temperatures combined with decreased circulation in these parts of the body creates direct damage to tissue cells. When tissue damage includes the small blood vessels, the affected areas undergo tissue death and are sloughed off.
Initial signs of frostbite include a cold stiffness to the tips of these body parts. As the days go on, the affected parts become hard and leathery before they separate from the healthy tissue below. The initial signs of frostbite in the calf may be subtle unless the feet are involved. In that case, the calf is very reluctant to rise, but appears otherwise healthy with a normal appetite. Diagnosis is made on the basis of the signs in the calf (sloughed tips of the ears or tail, pain in the rear feet) and the weather conditions present when the calf was born.
Frostbite is relatively uncommon in calves older than a few days, but older calves that are sick for any reason (e.g. scours) often have lower circulation to their extremities and may be susceptible. Severe wind and cold conditions may also cause frostbite in older animals. Bulls housed outside with minimal bedding in frigid conditions may be prone to frostbite of the scrotum, for example.
Once the signs of frostbite have been observed, it's often too late to significantly save the damaged tissue. However, steps should be taken to quickly warm up the affected areas to body temperature in order to minimize future damage. Directly apply warm water or warm towels to the area, after removing the calf from the cold conditions. The speed with which the tissue is warmed is not critical, but one should not vigorously rub the affected areas, as this will worsen the tissue damage.
Since treatment of frostbite is not often successful, prevention is key not only to minimize the sloughed ears and tails that cosmetically affect the calf, but also to prevent the pain and discomfort that accompanies the tissue damage. Providing newborn and ill calves with appropriate shelter and bedding during below-zero temperatures and wind chills is the primary method of preventing frostbite.