In many parts of the country the heat has subsided, replaced with crisp fall air. “We aren’t yet in the cold weather mindset, but if you’re finding yourself putting on an extra layer of clothes, chances are your calves are already experiencing cold stress.” This according to Ed Denton, a calf and heifer specialist with Purina Animal Nutrition located in New York.
Calves under three weeks of age can begin feeling cold stress much earlier than most people think. Denton notes that even at ambient temperatures of 60 degrees F and below, cold stress can hinder calf growth and performance. Cold stress can continue to affect calves over three weeks of age as ambient temperatures dip to 40 degrees F and below.
Denton offers some tips to help keep calves growing and thriving until temperatures begin to heat back up.
Use calf jackets
Calf jackets are a simple and effective tool to help calves conserve heat. Denton recommends using calf jackets on newborn calves and to continue using until they outgrow them. When using calf jackets, calf raisers should review their sanitation practices, as it is important to properly wash calf jackets between uses.
Maintain dry and deep straw beds
A deep straw bed can help calves’ ability to nest and conserve heat. Calf pens and hutches should always be clean and dry, notes Denton. A quick way to test whether or not bedding is dry is the knee test. If you put your knee down and it stays dry, your bedding is dry enough. If not, it is time to re-bed.
Denton uses a 1 to 3 bedding scorecard to evaluate whether or not bedding packs are deep enough based on how much of the calf’s legs are showing when they are lying down. If no legs are showing (optimal), the bedding score would be a 3; if half of their legs are showing (acceptable), the score would be a 2; if all of the legs are showing (unacceptable), the bedding score would be a 1. A score of 1 indicates that it is time to add bedding to the pack.
Offer consistent nutrition, formulated for cooler weather
Feeding calves a higher plane of nutrition, formulated for the season is particularly important as temperatures begin to drop. Denton recommends feeding calves 2.5 pounds of calf milk replacer powder per day to ensure that calves are receiving enough energy.
Providing the correct balance of fat and carbohydrates is key to achieving optimal energy intake, says Denton. A common misconception amongst calf raisers is that increasing fat alone in the calf diet during cooler weather will make up for a calf’s increased energy demands. Denton notes that a 50 percent increase in calf milk replacer powder can yield a 50 percent increase in energy. Alternatively, a 100 percent increase in fat alone in the calf diet may only yield a 12 percent increase in energy (NRC 2001).