Calves with drooping head or ears, a cough and nasal discharge and refusal to eat or drink—these are just some of the signs to watch for as you wean calves and receive stocker cattle this fall.
These symptoms and others could indicate that bovine respiratory disease (BRD), also referred to as shipping fever, has infected a single animal or your entire herd.
BRD can be a costly proposition for cattle producers—not only from the perspective of the dollars spent on treatment, but also from its effect on the performance of cattle. The disease often results in lower average daily gains and reduced feed efficiency.
Symptom checklist. Clinical symptoms usually develop within 14 days after weaning, according to information from the University of Minnesota College of Veterinary Medicine.
Early signs include depression, anorexia and dull eyes. When these symptoms occur, sort the cattle and check for fever. Temperatures over 104°F can indicate the onset of BRD.
Later symptoms include rapid or labored breathing, droopy ears, coughing, diarrhea, staggering, regular nasal discharge and sudden death.
Producers closely monitor calves twice daily for the first few weeks after weaning and receiving. “The onset of BRD can be rapid, but it most often appears with early clinical signs. Left untreated, calves with severe BRD will die from asphyxiation,” according to the University of Minnesota recommendations.
Treatment. As soon an animal shows symptoms, remove it from the rest of the herd and begin antibiotic treatment. Monitor the animal closely to see if it responds to treatment.
A second or even third treatment may become necessary. “A general rule of thumb is to follow a three-treatment protocol,” says Lee Bob Harper, managing veterinarian for Pfizer Animal Health.
After the third treatment, you are just wasting dollars and not improving the life of the animal. In this situation, consider realizing (railing) the calf if the appropriate drug withdrawal time has lapsed, or euthanasia in cases where it is warranted from a welfare perspective.
According to one study, animals that require two or more treatments for BRD return $184 per head less than animals that require only one treatment, demonstrating the importance of managing properly to improve the first-treatment success rate.
In some instances, your veterinarian may recommend metaphylaxis, or mass medication of a group of cattle to eliminate or minimize an expected outbreak of the disease. Research shows that using metaphylactic anti-microbials reduces BRD-related death losses and sickness rates compared to cattle that receive no treatment. Your veterinarian can determine if this course of action is warranted, depending on the source of your cattle.
Cattle from a known source and background that have been preconditioned may not require mass treatment. However, cattle from an unknown source and background may require a metaphylaxis protocol, Harper says.
This practice should be used in addition to a complete health program including vaccinations—not in place of vaccinations.
- October 2010