Veterinarian’s Corner: Effectively Address Respiratory Challenges

By Dr. Rob Farruggio, Jefferson Veterinary Clinic, S.C.
Respiratory disease in calves is one of the common issues many dairy farms encounter. The key is to identify respiratory challenges quickly and address the areas needing improvement. Calves raised in buildings (individual stalls or group pens) can have different challenges than those raised in hutches. We also see differences between pre-weaned calves and weaned calves, and these respiratory challenges can either be seasonal issues or year-round.

According to the Dairy Calf and Heifer Association Gold Standards, a goal for respiratory disease occurrence should be less than 10 percent for calves up to 120 days of life and less than 2 percent from 120 to 180 days of life.

Another value that should be monitored on farms is how many of the cases are repeat cases. This is an indication of treatment failure and should be cause for concern. Treatment failures for a medication protocol should be less than 20 percent. In other words, for every 10 calves treated, at least eight of them will successfully recover without recurrence. Follow these tips for both management styles and age groups to address and reduce respiratory challenges.

Provide 

• Quality colostrum
  • Feed an appropriate amount of a high-quality colostrum within one hour of birth. Calves receiving quality colostrum will have a better-functioning immune system.
  • Periodically monitor calves’ blood total proteins to assess colostrum management.
• Clean, dry bedding daily
  • If the bedding is wet, it will add moisture to the air, which supports the growth and spread of bacteria and viruses in the air. It also chills the calf, which then increases the energy demands and, subsequently, weakens the immune system.
  • The amount of bedding is also important because it provides warmth for the calf. The bedding should be deep enough for the calf to nestle into the bedding so the legs appear covered.
• Ventilation
  • Fresh air needs to be provided to the calf and should be changed at least four times per hour within a building facility.
  • Air movement can be assessed by using a fogger to see how the air is moved and exchanged within a facility. Work with a veterinarian or specialist in ventilation to perform the test and determine if changes need to be made.
  • Calves in hutches should be sheltered from severe weather, such as snow, wind and rain. In the heat of the summer, ensure that ventilation holes in hutches are open, or simply elevate the backs of the hutches.
• Nutrition
  • Calves need to be fed proper amounts of whole milk or milk replacer two to three times a day. Work with a nutritionist to develop a plan that is appropriate for your facility. Poor nutrition can starve the calf as well as stress and weaken the immune system.
• Vaccination
  • Discuss with your herd veterinarian whether the use of vaccines may help prevent respiratory challenges for your facility. Vaccine protocols should be designed around the needs of the specific operation.

Identify sick calves quickly

• Observe the calves at least twice a day for early signs of illness, such as weakness, reduced drinking, coughing, drooped head/ear(s) and/or increased breathing rate.
• Once a sick calf is identified, start by evaluating the calf’s temperature. Calves with pneumonia will typically have temperatures greater than 103 degrees F. Calves without a raised temperature that are coughing may not have pneumonia; rather, the coughing may be a sign of poor air quality. Work with your herd veterinarian to develop a proper treatment protocol that determines when treatment is necessary.
• When treating calves, proper calculation of a dose based on a known weight will decrease treatment failure. The use of a weight tape will help estimate a calf’s weight.
• Record all treatments, including calf identification, date, medication used, dose, route of administration, and staff member performing the treatment. This will help track the success of a protocol/medication.
• The scoring system from University of Wisconsin-Madison School of Veterinary Medicine may help you identify signs of pneumonia.  It also describes how to score the degree of pneumonia present.
• In cases of respiratory disease, calves receiving early intervention usually have a higher success rate since they do not become chronically infected.
• The use of ultrasound has also been shown to help assess the degree of damage within the lungs.

Monitor recovery

• Continue to assess the calf daily to ensure the calf fully recovers.
• Re-evaluate the treatment plan if treatment failures become prevalent.

Additional management and facility assessment

• The herd veterinarian can also perform deep pharyngeal swabs to identify the causative agent. This will help identify the cause of the respiratory challenge and assist in deciding whether treatment or vaccines may be of value.
• Environmental audits using ATP meters can be performed to identify areas in the facility that may be harboring bacteria. Cleaning and disinfecting protocols can be developed, if necessary.