Early detection, rapid response and aggressive treatment are the keys to effectively treating bovine respiratory disease (BRD), more commonly known as pneumonia, says Tom Shelton, DVM, MS, Intervet/Schering-Plough Animal Health.

At the March Dairy Calf and Heifer Conference in Lexington, Ky., Shelton discussed the anatomy and physiology of the bovine respiratory system and best management practices to most effectively manage respiratory disease. "The short- and long-term effects of pneumonia are nothing to sneeze at," Shelton said. "Pneumonia is a critical issue on dairy farms, costing you time and money to treat calves now and negatively affecting an animal's health and productivity far into the future."

Pneumonia is the most important disease in calves older than 30 days and according to the National Animal Health Monitoring System (NAHMS), results in an average loss of $15 per calf per year. In addition, long-term effects of pneumonia include a negative impact on growth, reproductive performance, milk production and longevity.

Cattle lungs are small, relative to the animal's size, and prone to infection. Compared to other organs, they also have the most potential to decrease future performance from lung damage which persists throughout the animal's life and cannot be repaired. Another challenge is the growth rate of respiratory bacteria. Shelton said bacterial populations can double every 30 minutes, and a single infectious BRD organism can explode into trillions in less than 24 hours.

"With the rapid snowball effect of bacteria, it's critical to identify and treat BRD symptoms immediately," explained Shelton. An emerging respiratory pathogen, Mycloplasma bovis, can result in ear and joint infections, as well as mastitis and abortion in adult cattle.

Early intervention
Effective colostrum management and vaccination programs are two great steps toward prevention. But even the best managed operations can and will have pneumonia cases. "The solution to most of these challenges is early detection," said Shelton. "If treatment is started too late or stopped too early, failure in treating the disease is likely to occur."

"Detection of pneumonia is a problem on calf ranches and dairy farms," said Shelton. "More than 50% of cases are under-diagnosed, and more than 40% are not detected early enough."

Treat infection and inflammation
"In addition to treating the infection, it's equally important to treat the inflammation," Shelton explained. "Inflammation is a vicious cycle, and it increases both pathogen virulence and the severity of the disease and causes tissue damage. And in BRD, inflammation often causes more damage than the pathogens themselves." Lung protection therapy is a management practice used in treating pneumonia that addresses both the infection and the inflammation. Use both a non-steroidal anti-inflammatory to quickly respond to the inflammation and an antibiotic to treat the bacteria.

A well-rounded approach
Shelton suggests the following best management practices to quickly and effectively respond to BRD symptoms:

  • Administer an effective BRD vaccination program.
  • Provide the right amount of antibody protection at birth by feeding one gallon of colostrum as soon as possible after birth and another gallon 12 hours later.
  • Monitor calves regularly for signs of pneumonia (cough, nasal discharge, watery eyes, drooping ears, labored breathing, increased breathing rate, depression, loss of appetite, slow to respond, weak muscles, etc.)
  • Quickly and aggressively treat the animal with both a non-steroidal anti-inflammatory and an antibiotic.
    • The anti-inflammatory will break the vicious circle of inflammation.
    • The antibiotic will act on the bacteria that initiate the infection process.
  • Monitor the animals’ health regularly to determine how she's responding to treatment.
  • Select follow-up treatment protocols if she doesn't respond.