By: Aimee Neilson, University of Kentucky Extension
Near-record lows and bitter wind chills have taken over much of the U.S. and livestock producers can take precautions to ensure the safety of lactating animals.
"Perhaps the most important thing producers can do is to take care of themselves in this extreme cold," said Michelle Arnold, University of Kentucky College of Agriculture, Food and Environment extension veterinarian. "If you get into trouble, you can’t be the caregiver to your livestock that you want to be."
When checking on livestock, producers should keep an extra set of clothes and a blanket in their truck. If producers get wet while doing chores, it’s important to have dry clothes to change into and avoid hypothermia. An extra pair of dry boots is a great plan as well.
When caring for any animal, water is critical. Livestock need water to maintain their health and their immune system.
"Lactating animals have an even higher need for water than young stock animals and mammals in their dry periods," Arnold said. "Livestock will not eat as much if they don’t have water available, and the immediate result will be less milk production."
Producers should check water sources several times a day. Arnold also warned that animals that consume salt without water available are at an increased risk for salt poisoning that can result in death.
Cold temperatures also increase animals’ needs for maintenance energy. Producers can either increase the animals’ feed intake or increase the energy density of the diet by feeding higher quality hay or adding more grain or fat to the grain mix.
"Consider separating younger and thinner animals that may not have the same internal insulation as conditioned, older animals," Jeff Lehmkuhler, University of Kentucky College of Agriculture, Food and Environment extension beef specialist said. "Supplement them accordingly or offer them higher quality forage if you have it available."
For dairy animals, producers should make sure teats are dry before turning animals out when the temperatures fall below 25 degrees Fahrenheit.
"Winter teat dips (powdered) can help reduce the chance of frostbite," Arnold said.
Treat signs of frostbite immediately since damage to the teat ends can quickly lead to damage of the keratin seal. That can in turn, allow mastitis-causing bacteria to enter the udder.
Most livestock can handle short periods of cold pretty well. External insulation is basically the depth and thickness of the hair coat and the thickness of the hide. Wind is a bigger enemy to livestock than the actual temperature.
Many areas of the United States are experiencing wind chills between 30 and 40 degrees below zero. The National Weather Service reported that skin can freeze within 10 minutes of exposure in those conditions.
"If you turn out an animal with a wet udder or teats, frostbite is almost a certainty," Arnold said. "Thin-hided breeds, such as dairy breeds, tend to have a lower insulating factor than thick-hided breeds like Herefords. The key is to give animals a place to get out of the wind, a draft-free place to go during extreme wind chill. The challenge is to make that space available and still provide enough ventilation to allow fresh air to circulate."
Dry bedding is also very important. If cows, goats or sheep lie in wet bedding, frostbite is a big risk. Producers also need to make sure the animals’ hair coats are kept dry and as clean as possible.
"The hair coat acts as an external insulation barrier that traps air, enhancing the insulating value," Lehmkuhler said. "If the hair is wet and full of mud, the air can’t get in and that reduces the insulating value and increases heat loss from the skin to the environment."
Lehmkuhler added that the density of the hair coat, and if it is wet or dry, impacts the wind chill temperatures at which cold stress is considered mild, moderate or severe. As little as 0.1 inch of rain can immediately impact cold stress severity by matting the hair down reducing its insulating ability. Acclimation time, hide thickness, fat cover and other factors will also influence the degree of cold stress that animals experience.