Boost Respiratory Health with Good Management – Dr. Sheila McGuirk, University of Wisconsin-Madison

With Dr. Sheila McGuirk, University of Wisconsin-Madison School of Veterinary Medicine
Calf respiratory health tends to be discussed most frequently during the fall and spring months, but it should be a top priority year-round, according to Dr. Sheila McGuirk, veterinarian and professor with the University of Wisconsin-Madison School of Veterinary Medicine.

Pneumonia, which is an infection in the lungs, can lead to poor growth, early culling or decreased production in the first lactation if not caught and treated early.

McGuirk said pneumonia is common as early as three weeks in dairy calves due to several factors:

• At this time, immunity from the initial colostrum feeding may be wearing off.
• Increasing nutritional needs may not be met (especially in cold weather).
• The bedding and air in the calf’s environment may be progressively more contaminated with time of occupancy.

These conditions can create a perfect storm for respiratory disease to develop.  According to McGuirk, four primary bacteria commonly cause pneumonia in calves:  Mannheimia haemolytica, Pasteurella multocida, Mycoplasma bovis or Mycoplasma dispar.  Viral pneumonia is less common in pre-weaned calves, but can be caused by Bovine Respiratory Syncytial virus (BRSv), Bovine Viral Diarrhea (BVD) or coronavirus.

Prevention and screening
McGuirk emphasized that respiratory disease can be effectively managed – or perhaps even prevented – through “the basics” of calf care.

First and foremost, your farm should have a very successful colostrum feeding program in place.  Move the calf from the maternity pen or calving area as soon as possible and place it in a clean, dry environment – this includes clean air as well as clean bedding.

As the calf grows, feed to its nutrient requirements for optimal growth.  Remember the calf demands extra energy during the cold months to maintain body temperature.

McGuirk also stressed the importance of a good health screening program.

Calves may be observed during feedings; look for calves that are slow to get up for a feeding or the last to get to the nipple. Also look for the calves that are the last ones to lie down after a feeding.

But McGuirk said good screening goes far beyond observation at feedings.  She said she recommends taking calves’ rectal temperatures and looking for signs of respiratory disease at least twice a week. Note that a higher temperature doesn’t automatically indicate pneumonia.  However, when it occurs along with a cough, nasal discharge, eye discharge or an ear infection, pneumonia is very likely a problem.

Coughs may be spontaneous (you hear calves coughing as you work around them) or induced.  To induce a cough as part of your screening program, locate the calf’s wind pipe high up in the neck behind the jaw bone.  Hold it firmly and shake it a couple of times.  Multiple coughs could indicate pneumonia.

Early signs of an ear infection include ear twitching, digging at the ear with a foot or head shaking.  As the infection gets worse, you may notice the calf tip its head to one side if only one ear is affected; it will hang the head and extend its neck if it has an infection in both ears.

Treatment of pneumonia
To help you determine when to treat calves for pneumonia, McGuirk designed a Calf Respiratory Scoring Tool.  Click here to access the resource.

McGuirk said you should work with your veterinarian to decide the most appropriate pneumonia treatments for your calves. If caught early, respiratory disease can be cleared in about five to seven days of treatment.  Veterinarians may prescribe an antibiotic that provides five days of coverage with one injection, so the calf only needs to be treated once.  If the calf has an ear infection, the treatment period may extend to 10 days or longer.

According to McGuirk, calves with pneumonia caused by M. haemolytica or P. multocida, may respond to treatment more rapidly.  Mycoplasma can be more of a challenge when an ear infection is also present.  In fact, more research is needed to determine if an animal is ever truly cured from an M. bovis infection as this bacterium is known to cause a wide variety of disease challenges in adult animals as well.

Endemic pneumonia and culturing
If the initial treatment does not cure the calf’s pneumonia, your veterinarian may suggest that respiratory cultures from sick, untreated calves will help determine the exact pathogen and the best plan for pneumonia treatment going forward.

If your farm battles endemic pneumonia – frequent respiratory disease in multiple animals – McGuirk said it might be wise to take cultures two to three times per year to keep the treatment protocols current and effective.

Of course, the goal is to work toward great calf management so that calf pneumonia does not become a common problem.  Focus on colostrum management, optimal nutrition, a clean, dry environment, and a solid screening program for all calves.

McGuirk concluded, “Screening takes time and takes people, but it will pay itself back in early detection and effective treatment.”