Ivermectin sensitivity or MDR1 gene defect DNA testing for the Border collie dog breed

Ivermectin sensitivity or MDR1 gene defect DNA testing for the Border collie dog breed

Health & Safety

The Border collie is the world’s most intelligent working dog breed, and these incredibly smart and very lively dogs are still widely used for working herding roles in the UK today, as well as being widely used in all manner of canine sports too.

Border collies do also make for excellent domestic pets within non-working homes too, as long as they are provided with enough exercise and stimulation to keep them happy, which means that Border collie owners need to spend quite a lot of time walking and entertaining their dogs!

As you might expect from a dog breed with such a long and valued working history, the Border collie is on the whole a very robust, hardy and healthy dog breed that is used to spending lots of time outside in all weathers, and that doesn’t tend to fall ill or be overly delicate in demeanour.

However, as is the case for the vast majority of recognised dog breeds in the UK, there are a number of hereditary problems that have established themselves within the Border collie dog breed over time, which can affect the dog’s quality of life, longevity, or have implications for their care and management.

One hereditary health issue that is recognised within the Border collie breed is called Ivermectin sensitivity or MDR1 gene defect, and this condition causes affected dogs to be highly sensitive to certain drugs that are commonly used within veterinary medicine, within products such as some wormers and also certain medications for health conditions too.

Dogs who are sensitive to such substances are apt to react very badly to the administration of even small doses of such medications, which can cause toxicity and even death as their bodies are unable to properly process and eliminate these substances in the normal manner.

You can’t tell from looking at a Border collie (or any other dog) if they are likely to react badly to a certain medication, but fortunately dogs who might have higher risk factors for such sensitivities can be DNA tested to find out whether or not such medications are safe to use for them.

The DNA test for Ivermectin sensitivity or MDR1 gene defect identifies the faulty gene that leads to the sensitivity itself, and enables dog owners and breeders to identify the risk factors for their own dogs. This in turn means that the use of such medications can be avoided, and also that Border collie breeders can choose good mating matches to produce litters that will not in their turn inherit the same sensitivity.

In this article we will outline how Ivermectin sensitivity affects dogs, how it is inherited and passed on, and how to get your Border collie DNA tested to find out if they have inherited Ivermectin sensitivity. Read on to learn more.

What is Ivermectin sensitivity or MDR1 gene defect?

Ivermectin is a medication that is widely used as an antiparasitic agent, which can be used to eradicate pests such as worms. However, Ivermectin-sensitive dogs are generally also sensitive to quite a wide range of other medications with similar ingredients too, including a large number of veterinary drugs designed for use on a variety of health conditions such as heart problems, diarrhoea, and allergies. This means that the medications used to treat a dog with Ivermectin sensitivity must be chosen with great care to avoid causing a serious and acute bad reaction in the dog in question, which may ultimately prove fatal.

Virtually all of the medications that Ivermectin-sensitive dogs can react badly to have alternatives available that can be used safely – but this can only be achieved if the dog’s sensitivity is known in the first place, which is where DNA testing holds real value for dog owners.

How is Ivermectin sensitivity or MDR1 gene defect inherited?

Ivermectin sensitivity or MDR1 gene defect is a hereditary health condition that is passed from parent dogs to their offspring by means of autosomal recessive heredity.

This means that as well as being able to find out the status of an individual dog by DNA testing for Ivermectin sensitivity in the Border collie, by testing both parent dogs within any planned mating match, you can also work out what status their puppies will have too.

Here’s how the status of the two parent dogs can tell you the status that their litter will have:

  • Two affected dogs will have an affected litter.
  • Two clear dogs will have a clear litter.
  • Two carrier dogs will have a litter with each pup having a 50% chance of being a carrier, a 25% chance of being clear and a 25% chance of being affected.
  • A clear dog and an affected dog will produce a litter of carriers.
  • A clear dog and a carrier will produce pups with 50:50 chances of being clear or a carrier.
  • A carrier and an affected dog will produce pups with 50:50 chances of being a carrier or affected.

How can I get my Border collie DNA tested for Ivermectin sensitivity?

Finding out whether or not your Border collie is sensitive to Ivermectin and related drugs can be established with a simple DNA test. To get your Border collie DNA tested for Ivermectin sensitivity, you just need to ask your vet to take a blood sample or cheek swab from your dog for testing.

This sample is then sent off to an approved testing laboratory, who will return the result of the dog’s status to their owner.



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