Dealing with sick calves is not a unique or new challenge across the cattle industry, especially when it comes to bovine respiratory disease (BRD). Even after taking steps to build immunity and mitigate BRD risk, we know some calves are going to get sick. That’s why cattle producers need to put on their detective caps and look for the smallest clues that will lead to an early BRD diagnosis.  

Sick cattle can be hard to identify in a group, making a keen eye and solid evaluation protocol essential. With the proper investigation tools, producers can maximize their chances for success when treating sick cattle for BRD.  

Look for clues  

The sooner producers can take action and treat a sick calf, the more likely the calf will respond to treatment. According to Matt Washburn, DVM, MS, Boehringer Ingelheim, finding those calves early can be a real challenge. Having trained personnel to assess the following list can be the difference in whether treatments are successful or not:  

• Appetite is one of the easier indications of a sick calf. If calves go from consuming an accessible diet to not eating as much, or in some cases not eating anything, we should be flagging them for further evaluation. 
• Key body language that indicates a calf may feel sick includes droopy ears, resting more than normal, and moving sluggishly or slowly.  
• A calf may suffer from a variety of visual symptoms, all depending on what is causing them to get sick. Drainage from either the eyes or nose is an indicator of BRD.  

These clinical signs of sickness are not necessarily unique to BRD, but are a sure way to flag animals that are becoming ill.  

Evaluate the evidence  

“It’s important to utilize a veterinarian to train staff to examine cattle for disease in order to decide if an animal needs to be treated,” said Dr. Washburn. “The initial exam will usually begin with evaluating attitude and appetite.”  

When an animal is showing symptoms of being sick, it is essential to pull that animal from the herd and evaluate them further. High body temperature and irregular breathing can both be indications of livestock that need treatment. 

Some operations may identify and evaluate cattle using the D.A.R.T. assessment, which looks at four areas: Depression, Appetite, Respiratory rate and Temperature.  

“D.A.R.T. is an easy way to remember what we are looking for when we suspect BRD,” shared Dr. Washburn. “However, it’s also essential to be consistent when checking cattle — whether it’s the frequency of cattle checks or ensuring the person performing them is properly trained.”  

Kick out the culprit  

Once it’s determined a calf needs to be treated, producers should find an antibiotic that best helps the calf fight infections. But not every antibiotic is created equally, making it worthwhile for producers to find a fast-acting, long-lasting antibiotic that targets all four BRD-causing pathogens - Mannheimia haemolytica, Pasteurella multocida, Histophilus somni and Mycoplasma bovis.

”Long-acting antibiotics can give us the opportunity to get that animal back to its home pen sooner, which usually means less stress for the calf and, ideally, a faster recovery,” said Dr. Washburn. “It’s important to allow sufficient time for an antibiotic to work before deciding whether re-treatment is warranted. I recommend working with a veterinarian to establish guidelines on how long to wait before deciding to re-treat. This waiting period depends on what antibiotic is being used.” 

Diagnostic testing with the help of your veterinarian can also be a useful tool to pinpoint the cause of respiratory infections.

The earlier you identify subtle signs of BRD, the greater the chance for an antibiotic to be effective. Implementing these investigation tools can help diagnose a sick calf and reveal BRD as the problem, sooner.  

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