REDFIELD, Iowa - Rapid temperature swings across major cattle-producing regions in early March are increasing health risks for newborn calves, prompting livestock experts to urge producers to closely monitor calf health as extreme weather patterns continue across the United States.

According to beef cattle specialists and veterinarians, dramatic shifts from freezing temperatures to springlike warmth can place significant stress on young calves, potentially leading to sickness, slower growth and higher mortality rates that ultimately affect profitability for cow-calf operations.

Mark Johnson, beef cattle breeding specialist with Oklahoma State University Extension, said producers should pay particular attention to calves born during recent cold snaps as temperatures quickly rise. In parts of the southern Plains, temperatures recently moved from single-digit lows to daytime highs near 70 degrees Fahrenheit, a swing that can strain young animals still developing their ability to regulate body temperature.

The ideal comfort range for newborn calves is between 55°F and 70°F, a window that allows calves to maintain body heat without expending extra energy. When temperatures move outside that range, calves may experience cold or heat stress, both of which can lead to economic losses through increased illness or death. Indirect impacts can include reduced weight gain, weaker long-term performance and lower survival rates in the herd.

Veterinary experts emphasize that calf health begins before birth through proper herd vaccination programs. Jody Wade, senior professional services veterinarian for cattle with Boehringer Ingelheim Animal Health, said the immunity calves receive from colostrum - the nutrient-rich first milk from the cow - plays a critical role in early disease protection.

Ensuring cows are vaccinated during pregnancy helps them develop antibodies that are then passed to calves through colostrum immediately after birth, providing passive immunity that protects calves during their early weeks of life. Calves that fail to receive adequate colostrum often have weaker immune systems and may require earlier vaccination protocols to reduce disease risk.

Respiratory disease is one of the most common threats during early calf development, and strong immunity significantly improves performance throughout the animal's feeding cycle. Producers should watch closely for early warning signs that may indicate illness or stress in young calves.

Johnson said the first symptoms often include reduced nursing behavior, abnormal body temperature and unusual or erratic behavior. The normal rectal temperature for a healthy calf is about 102.5°F, and deviations from that range may signal infection or stress.

Early detection is essential because treating illness quickly can reduce the long-term production losses associated with disease outbreaks in young livestock. While cold weather is often seen as the primary risk to newborn calves, experts say heat stress can sometimes be more harmful, especially when temperatures rise rapidly.

Young calves have an immature thermoregulation system, making it harder for them to maintain stable body temperatures compared with adult cattle. During periods of heat stress, calves may lose appetite, eat less and become dehydrated more quickly, weakening their ability to grow and resist disease.

Although cattle can adapt to gradual seasonal changes through acclimatization, sudden weather shifts can trigger thermic stress that overwhelms young animals.

Weather conditions across much of the country remain highly variable, according to agricultural meteorologists. Recent storms across northern states from Montana through Michigan have brought widespread precipitation and snowfall, while areas farther south across the Plains remain relatively dry.

Forecasters expect another burst of colder air east of the Rocky Mountains following a weekend storm, followed by unseasonably warm temperatures spreading across the Plains and Midwest next week. Some areas could see temperatures above 70°F or even record highs before the end of March, increasing the potential for weather-related stress in livestock operations.

With weather patterns expected to remain active in the coming weeks, livestock specialists recommend producers closely observe newborn calves during periods of rapid temperature change. Even as warmer spring weather arrives, calves spending long hours in the sun may still experience overheating, which can be less obvious than cold stress but equally damaging to their health. Careful monitoring, strong vaccination programs and ensuring calves receive adequate colostrum remain among the most effective management strategies for protecting herd health and preserving productivity in cow-calf operations.