Tips for Winterizing your Calf Care.

 By Jaclyn Krymowski.

 Winter can be an especially stressful time for both the herd and farm employees. Perhaps the worst of this is felt when it comes to keeping the most vulnerable assets to your herd, youngstock, healthy during the frigid temperatures.

Not only is the health of both dam and calf at calving a tall order this time of year, so is maintaining optimal health for calves from the moment they hit the ground.

When they are first born, calves have brown fat, which releases energy for body heat. On average, they are also born with 3-4% total body fat. Even with this biological defense in place, in cold temperatures, this amount of natural body heat won’t provide energy to maintain body temperature for long, especially if the animal is exposed to windchill dampness.

The early weeks of a calf’s life are crucial to thermoregulation and providing natural defenses against the elements. Once calves begin to ruminate later in life, they are better able to keep warm through the heat produced during feed digestion. While older animals have a lower surface area to body weight ratio, which allows them to withstand cooler temperatures, calves can experience cold stress starting at just 60 ℉.

Providing young animals with enough nutrients and energy to both build their immune systems and generate enough energy to keep warm is a challenge, especially when cold weather makes it tempting for calf care workers to fudge protocols.

Mitigating cold stress is essential for young stock to avoid higher levels of susceptibility to diseases such as pneumonia and scours.

Start with nutrition
As always, calf nutrition plays a huge role in setting young animals up for success, especially during the winter months.

Among the most critical practices is to provide colostrum as soon as possible. Stressful environments like cold weather may hasten gut closure.

In the article Get Your Dairy Calf Nutrition Program Ready for Winter, Tom Earleywine of Purina Animal Nutrition writes that providing additional energy in a calf’s diet when temperatures drop below 60 ℉ prevents them from pulling energy from their reserve body fat. Limiting energy not only impacts growth and development but can also suppress the immune system.

In Earleywine’s article, he mentions adding a third feeding as an easy way to increase nutrition when the temperature drops. If three feedings are not possible, University of Minnesota Extension educator James Salfer notes suggests increasing the amount of liquid at each feeding.

And while milk quantity is important, milk quality is equally critical to ensure the calf’s nutritional requirements are met.

“Total energy is the most important factor to consider when choosing a seasonal milk replacer,” writes Earleywine. “To maximize energy levels, look for a milk replacer with 20% fat and at least 265 protein. Milk replacers with more than 20% fat can decrease growth and hinder starter intake.”

He explains that adding a “fat pack” can make the calf’s diet unbalanced. Properly balanced milk replacers will help a calf break down and use fats well, plus boost the intake of starter feeds.

In addition to making sure the calf gets enough milk, make sure it also gets enough water. Just as in the heat of summer, water is equally as important in cold temperatures because the dry winter air can dehydrate calves.

Earleywine recommends offering warm water (100-105 symbol degrees F) immediately after each milk replacer feeding to help hydrate and maintain the calf’s body temperature.

Post-weaning
Calf care doesn’t stop once they are weaned. Adjusting the requirements as the heifer continues to grow is important so her requirements are continually met.

Managers need to continue to manage calves once weaned so they don’t impact the positive growth weights the calves obtained during the pre-weaning stage, writes Dr. Maurice Eastridge of the Ohio State University in his article Managing Dairy Calves and Heifers During the Winter Months.

He adds that energy requirements need to be considered for the weaned heifer as overfeeding corn silage can lead to an over-conditioned heifer which comes with increased cost and risk of related diseases.

Although heifers are better able to withstand the cold as they mature, their nutrition and management are just important so they can meet important production goals.

Eastridge notes that the average daily gain of a weaned heifer and how they are managed during the winter months has a strong impact on breeding and calving goals.

Housing and additional details
Winterized housing is essential for both young calves and weaned heifers to thrive during the cold months. The natural insulation that comes from the hair coat (plus rumen fermentation in older animals) can be negatively impacted if they are not kept dry. Besides chilling the calf, wet bedding also is a poor insulator and draws out the calf’s natural body heat instead of trapping it for additional warmth. Deep, dry bedding is by far the most cost-effective way to keep calves warm both in hutches and in barns.

For younger or ill animals, a calf jacket also goes a long way to helping retain as much body heat as possible. According to some research, a good calf jacket can increase body insulation by 52%.

As in the summer, sufficient airflow throughout housing is a huge boon to respiratory health. Good air circulation helps prevent an environment where pathogens could grow if it’s damp and has no air movement.

It should be noted that natural airflow should be considered in determining pen arrangement and housing. For example, calves that are housed naturally downwind from the rest of the herd or manure storage are at greater risk of contracting airborne pathogens, even with natural airflow.

Maintaining calf health is a year-round job. There are challenges with each season. But if the groundwork for good nutrition and a sufficiently warm and dry environment is in place,  most healthy calves can successfully ride out climate extremes.