Although it is rare, white footed herding breeds such as Border collies, Corgies and Australian shepherds can have a genetic mutation that makes them sensitive to ivermectin and several other drugs including some chemotherapy medicines.
For example, a dog named Bristol who had the genetic mutation almost died as a result of the mutation. Bristol was barely responsive and suffering from seizures. It took months of treatment including a mechanical ventilator and rehabilitation to bring her back to normal health. Bristol had eaten the droppings of sheep that had been recently dewormed with ivermectin, which is what caused her health issue.
It is easy to determine if your dog has the genetic mutation by asking your veterinarian for a simple test to determine if your dog has the genetic mutation. The test involves using a small brush to swab the inside of your dog’s mouth. The swab is sent to a laboratory for the results.
This is an easy preventative way to protect your dog, especially if your dog is around barns, livestock or used for herding trials. All herding breeds should be tested to be safe. It would be a good idea to test all herding breeds whether they are white-footed or not. Rather be safe than sorry.