Editor’s note: This tip is provided by Roy William, Dairy Calf and Heifer Association member. For more housing guidelines for young calves, refer to Dairy Calf and Heifer Association's Gold Standards.
Maintaining good health and satisfactory growth rates in young calves requires a mix of good nutrition and good environment, such as those established in DCHA's Gold Standards I.
The University of Minnesota extension service, as well as the University of Wisconsin, Penn State University, South Dakota State, and others, provide extensive cold weather, calf care guidance through their respective websites. Even though the DCHA Gold Standards I offers target housing standards specifically for Holstein calves from birth to 6 months of age, they can easily be adapted to all dairy breeds.
Here are some of the basics:
1. Provide a clean, dry, comfortable resting area.
Clean: free of pathogens, free of dust, free of water spray. Rub a white towel over the surfaces of the calf's pen. If you can see dust or other contamination on the towel, or it is damp, you may have a sanitation issue.
Dry: get down on your knees in the calf pen and crawl around. Now get up. Are your knees wet? If so, the calf will get wet, too.
Comfortable: lie down on the bed you provide for the calf. Are you comfortable after you lie there for two hours? No? Then the calf will not be, either.
2. Adequate ventilation with clean air: the air that calves breathe must have a very low level of dust, toxins and disease-causing microorganisms. Some published measurements have reported levels of bacteria inside a calf barn to be 100 times the levels found outside the barn. For existing barns that are experiencing too many sick calves, a positive pressure ventilation system may be installed (see: Improving Calf Barn Ventilation with a Bit of Fresh Air" by Brian Holmes, University of Wisconsin - Madison).
3. No cold drafts: we all know about "wind chill." The main defense that a calf has against loosing body heat is a layer of air trapped in its fur. If the calf is subjected to a draft, that layer of trapped air is disrupted, and the calf may become cold-stressed.
4. Minimum (no) frost or condensation: if you see large patches of frost or moisture, it means that there is too much moisture in the air, and/or there is not enough air circulation. Most disease-causing bacteria love moist areas, so the more dampness you see, the more bad bacteria there are in the air to get in your calves.
If you think you are "doing everything right" and still have sick calves, you should consider getting an air quality test done by a reliable air quality testing service. Some of the larger feed suppliers may be able to assist you with air quality testing and evaluation.