When temperatures drop, a good calf jacket can make a big difference for young calves. Cold weather forces calves to burn extra energy just to stay warm, and a jacket helps them hang on to that energy so they can keep growing strong.
“A cold calf will need to use energy to try to maintain its body temperature; energy that would normally be devoted to growth and maintaining a healthy immune system,” says Cassie Yost, dairy Extension educator at Pennsylvania State University.
But not all jackets are created equal. Even the best one will fall short if it is not managed well. Here is what to look for in a solid calf jacket and how to get the most out of it once winter sets in.
Choose a Jacket Built for Warmth and Durability
A good calf jacket should balance warmth, fit and durability. Calf specialists recommend choosing a jacket with an outer waterproof or water-resistant shell to protect against wind and moisture. Inside, insulated liners should help trap heat without being too bulky, allowing calves to stay warm without restricting movement.
“A clean, dry hair coat provides greater insulation from cold than a wet, matted coat, and calf jackets can be used to further insulate young calves,” Yost adds.
Fit matters too. Jackets should sit close to the body without gaps, allow full range of motion and adjust easily as calves grow. Coats with multiple strap points help maintain a snug fit without rubbing.
But once a jacket is on, it needs regular checks to make sure it still fits and keeps the calf comfortable.
“Leg straps can quickly become too tight and dig into the back legs of calves, easily causing open sores,” Yost says. “Remember that putting a jacket on a newborn calf is not a once-and-done action. It requires monitoring as the calf grows and as the weather conditions change.”
Keep Them Clean and Dry
Cleanliness is just as important as insulation. Jackets that trap moisture or bacteria can do more harm than good.
“Remember to wash jackets in between uses to remove any built-up mud or manure to ensure a clean, dry jacket is available for the next newborn calf,” Yost says.
Jackets must also be fully dry before reuse. Wet coats lose insulation and can chill calves even faster than leaving them bare. Farms should keep enough extras washed and ready so calves never go back into a damp coat.
Start Jacket Use at the Right Time
Knowing when to begin using jackets matters. Severe cold puts young calves under 3 weeks of age at the greatest risk.
“Calf jackets are most useful for calves under 3 weeks of age and especially for any calves that are sick and struggling with illnesses,” Yost says.
Many farms rely on benchmarks such as the 90-degree rule, where the daytime high plus nighttime low equals 90°F or less, to decide when jackets should go on. Others watch for several nights below 40°F. Once jackets are in use, they typically stay on through the winter and into early spring.
Warm spells require extra attention.
“If the calf is sweating during the day, that damp calf will get chilled once the temperatures begin to fall at night,” Yost explains. “Sweating followed by chilling will negate the purpose of the jacket.”
Knowing when to take jackets off is just as important as knowing when to put them on.
“As calves grow, calf jackets can be removed once that calf is growing well and consuming grain. Removing jackets at a reasonable time while the calf is still on milk will help them adapt to their environments now that the added protection of the jacket is removed,” she adds.
Other Details Matter
Even the best jacket can’t make up for poor bedding. Calves need a deep, clean and dry bed to nest into. Jackets are a helpful layer, but they work best when the calf’s environment is warm, dry and well-bedded.
Fresh straw, shavings or other bedding materials should be replenished regularly so calves can nest, curl up and stay insulated from cold floors. Bedding also helps wick away moisture, which reduces the risk of chilling and illness. When the ground is frozen or damp, adding extra bedding becomes even more critical.
Jackets Help Calves Use Energy Wisely
Cold calves burn extra energy just to stay warm, which takes away from growth, immunity and overall health. A well-chosen jacket helps them hold onto that energy so it goes toward what really matters.
When paired with good management and proper bedding, a clean, dry, well-fitting jacket can help young calves handle the cold months with less stress.
