Keeping dairy cows healthy in winter

(Louisa Shepard, Penn Vet communications specialist)

KENNETT SQUARE, Pa. — This year’s unusual winter weather has presented a significant challenge to dairy farmers and their animals. The wide temperature swings and wet-warm weather in the Northeast and Mid-Atlantic regions have stressed cattle and led to an increased incidence of disease.

Experts at Penn Vet’s New Bolton Center have seen an increase in pneumonia cases, ranging from sudden death of apparently healthy animals to chronic illness and poor production, particularly in growing heifers and calves, but also in adult cows.

Herd health

While these weather challenges are not as catastrophic as the blizzards out West, they can significantly impact productivity and herd health. Dr. Meggan Hain, staff veterinarian in Penn Vet’s Field Service and the Marshak Dairy at New Bolton Center, offers several important tips for preventing and addressing pneumonia in dairy cows.

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1. Good Air

The most important measure in preventing pneumonia is good ventilation. While our instinct is to close everything up and batten down the hatches in winter, this can be significantly detrimental to air quality and cooling capacity, particularly on warm days.

Open the curtains: On warm, humid days, don’t forget to open the curtains to allow plenty of air flow. If in doubt, open everything up — remember these animals are wearing their winter coats.

Open windows. Open any windows or vents that have been closed to allow good air flow. Opening up barns as much as possible to prevent stagnant areas is essential. In this unusual weather, heifers housed outdoors with a run-in shed tend to do better than those housed indoors, because of the ventilation.

For older barns, consider putting in forced ventilation, adding fans as a quick fix in a pinch. However, use fans with caution to avoid chilling young calves. A better solution is a well-designed tube ventilation system. The University of Wisconsin School of Veterinary Medicine has developed a well-designed ventilation system that can be adjusted to fit most barns.

Penn Vet’s Dr. Billy Smith is a qualified consultant, who can design one for your facility. For the best results, consider having an air-flow and air-quality test run on your facilities under normal working conditions. This includes monitoring air quality at the animal level (for calves, often at the straw level), and air flow throughout the barn. Penn Vet’s Field Service can perform these tests.

2. Vaccinations

The key to using vaccinations as prevention is to give the vaccination before the disease challenge. Consult your veterinarian: The best way to have a vaccine program that will work well for your farm is to consult with your veterinarian, who can develop a program that will be both effective and practical for you.

Consider adding pneumonia-specific vaccinations just before the most challenging times of early and late winter to provide added protection for your animals. Some of the intranasal vaccines are particularly helpful as they provide a better localized immunity in the airways.

Again, talk with your vet about which vaccine combinations and routines would work best for your farm. Make sure that the animal is healthy when it receives the vaccination so that it can mount a good response. It is essential that the vaccine is handled appropriately. Vaccinations that have not been kept cold, are expired, are poorly mixed, or are administered with old or dirty equipment are ineffective.

3. Avoid added stress

The unusual weather is already adding stress, so during this time, avoid transporting the animals, excessive intermingling, or bringing in new stock from outside sources or sale barns.

4. Monitoring

Catching an illness early will give the best chance of effective treatment and prevention of long-term damage. Remember the old-look-see. Don’t forget during your chores to take the time to watch the animals and look for signs of illness: animals that are isolating themselves or slow to join the group, droopy ears, sunken eyes, lying down with a dull attitude, poor condition, as well as snotty noses, coughing, and increased respiratory effort and rate.

If you suspect an animal is ill, take its temperature. Normal temperatures should be 100.5-102.5 F. Talk to your vet. Consult your veterinarian for treatment protocols that fit your farm. Consider posted protocols so you are ready to respond to a problem when it arises, or call your vet for case-specific advice.

5. Facing an Outbreak

Sometimes, despite our best efforts, we will face a disease outbreak. In these cases, fast and aggressive treatment is the key to success.

Treat the affected animals early and aggressively to prevent long-term damage to the lungs. Consider isolating them to prevent spread of the disease, and to aid in monitoring their feed intake and progress. Treatment to decrease the fever with an anti-inflammatory, and possibly supportive fluids, will help to make the animal feel better, eat better, and heal faster.

Again, it is essential to consult with your veterinarian on treatment protocols that will work well for your farm and staff. No article on pneumonia would be complete without a mention of blanket treatments, including feed through antibiotics such as the Tetracycline Crumbles. These treatments can be effective in helping to address an outbreak in a large group.

Use these only under the consultation of your veterinarian, as these products are coming under stricter scrutiny by U.S. regulators. Even in the face of an outbreak, consider vaccinating healthy animals to help prevent the spread of disease.

While vaccinations add stress to the immune system and take time to provide protection, when used cautiously, they can help in an outbreak situation. In particular, intranasal vaccinations tend to provide quicker immunity in the respiratory system. Typically, winter weather is good for herd health and high milk production, as the big rumens in dairy cows constantly generate heat, and their large bodies preserve that heat.

Occasionally, with extreme cold, we will see issues with frostbite on teats, although this can easily be remedied with a good teat dip. Even young stock will grow thick coats, which help to conserve heat on the cold days. Little calves are less cold tolerant and will appreciate a calf coat and extra milk when it is cold at this time of year.