The old Far Side cartoon goes like this: Horse diagnosis for veterinarians Ð broken leg: shoot; bad foot: shoot; sore eye: shoot; etc.
When it comes to cattle producers performing pasture diagnosis, veterinarians say the practice of shooting penicillin is nearly as comical.
“Got a sick animal? Give it a shot of penicillin. If nothing happens in a couple of days give it another one. Wait a couple of days and if it’s still sick one more couldn’t hurt,” said Chris Clark, a professor with the University of Saskatchewan’s Western College of Veterinary Medicine.
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“It doesn’t work, but it sells a lot of penicillin and gives agriculture a bad name for over or misusing drugs in food animals.”
Clark said diagnosing disease in the pasture can be effective and improve producers’ bottom lines if done properly.
“Why do veterinary treatments fail? They fail in large part because it was the wrong diagnosis or treatment came too late,” he said. “So when a drug doesn’t work, stop using it. Step back and have a look at the diagnosis. Generally it was wrong.”
Clark recommends that producers carry a small, digital thermometer and make it the first tool they use when treating a sick animal.
He said producers should always check for a fever before administering antibiotics.
“No fever, no infection, no antibiotics,” he said.
“Antibiotics won’t work on fungus, viruses, toxicity or deficiency.”
Clark said producers should also pay close attention to the information sheet contained with each medication. Not only does it give information about the product’s active ingredients and withdrawal times, but also describes diseases the medication will treat.
“Procaine G (white penicillin) won’t treat scours because it doesn’t work very well in the stomach,” Clark said.
“And amazingly enough, scours isn’t listed on the information sheet. Yet we get plenty of cases brought to us at the (WCVM) clinic each year that have had several doses of Procaine.”
He said a veterinarian should be called for a diagnosis if an animal doesn’t respond to treatment within a few days or continues to deteriorate.
Sudden death in the pasture is rare and veterinarians should always be called, because toxicity is usually
involved.
“Anthrax, toxic algae contamination of water, those sorts of things are usually to blame if it’s a sudden death and for that an autopsy is usually needed,” he said.
“If you ignore the first one and there are a couple more, after that you may not feel you can afford to get professional help and it can only get worse from there.”
