Exercise Induced Collapse (EIC)

Last week I started a three week series on health issues in Labrador retrieves that you should become familiar with before you start the process of buying a puppy. These issues are also important if you already own a dog as you may be able to manage the problems if you already have a dog that is affected by one of the three conditions. Last week general information on hip dysplasia was covered. This column will cover a much lesser known problem called Exercise Induced Collapse or EIC for short.

I think the EIC has been around for a while but is just now coming to the forefront for buyers and breeders alike. EIC is a condition where affected dogs, as a result of strenuous exercise coupled with high levels of excitement actually collapse for short periods of time. The most recognizable symptoms are completely evident to anyone who sees them.

After 5–20 minutes of high energy exercise the dog will become weak in the hind quarters and ultimately get to a point where it becomes immobile. The dog will be wobbly on its hind quarters, seem uncoordinated and hazy and have no ability to move. Episodes of EIC will most likely last for about 15 minutes and after that period of time the dog will then return to a state where it will appear completely normal. EIC symptoms normally show up between seven months and two years of age. It is evenly distributed between the sexes and different colors of Labradors.

In very rare instances dogs have died as a result of an EIC event but for most animals here seems to be no substantial long term negative effects on the dog that suffers an episode of EIC. This assumes the owner limits the dogs' activity to low levels of exertion. After the dog recovers they act and behave normally as if nothing happened. There have been extensive amounts of research done on dogs that display EIC conditions and these results have been compared to dogs that are normal.

EIC was thought to have its roots in any or all of the following conditions. The conditions include low blood sugar, heat intolerance, cardiac issues and chemical imbalances. EIC in fact is caused by a mutant gene that is passed down from dog to dog. There are three possible EIC scenarios. They are EIC clear, EIC carrier and EIC affected.

EIC can now be diagnosed with a blood test. If your dog is EIC clear it means that it has two normal genes passed down from its parents and as the term indicates an EIC clear dog should show no signs of collapse during its lifetime. If the test results show the dog as EIC carrier it means that it has one mutated gene and one normal gene. Just like an EIC clear diagnosis an EIC carrier diagnosis will also have no problems with this condition. It just means that is has the ability to pass the one mutated gene down to approximately 50% of its offspring. An EIC affected test result will mean that the dog as two copies of the mutated gene. There are some EIC affected dogs that have not had any collapse episodes. There are several possible reasons for this. Maybe the dog has never been put in the position of extreme exercise or very high excitement. EIC affected dogs might very well live out normal lives as pets but would most likely suffer multiple and reoccurring issues if it was hunted or trained extensively.

So what does this all mean to a potential puppy buyer? It really depends on what you intend to do with the dog. If I were looking for a hunting dog I would only consider two options. Buying a puppy from a litter in which both parents were EIC clear or a second satisfactory choice would be if only one parent was clear and the other was a carrier. This breeding would possibly result in a puppy having only one mutant gene. Remember that an EIC carrier only will not suffer from EIC collapse episodes. It takes two mutant genes to be affected with EIC. This means that both parents would need to posses the mutant gene.

If you were purchasing a puppy that you ultimately wanted to use for breeding stock then a puppy out of a litter where both parents were clear would allow you a much greater variety of breeding options. You could breed your dog to another dog that was clear or one that is a carrier. Clear on clear means clear puppies. Breeding a clear to a carrier would result in puppies that were carrier only and not EIC affected.

The only true bad scenarios are litters where both parents are any combination of EIC carrier or EIC affected. This will mean that the puppies will almost always be EIC affected. These dogs would most likely suffer from exercise induced collapse episodes. Mating two dogs that are both carriers but not affected would dramatically up the odds that some of the puppies would be EIC affected and suffer collapses.

I would not be afraid to buy a puppy that was an EIC carrier. I have had them and they are going to perform like any non-carrier dog. The key here is to know the EIC status of the parents in order to insure that you do not end up with a puppy that has two mutant genes and will never be able to perform in the field.

If you question your prospective breeder about EIC and the status of the litter and they respond that they don't know or haven't checked, immediately move on to a different breeder. Any serious dog breeder will know the facts about EIC and the status of the dogs that they are using for breeding. Just as a said last week there is no greater heartbreak than training a dog to a high level only to find out to later that it has a bad hip or is EIC affected.

Hip dysplasia cannot be determined in a 7 week old puppy but EIC can. This can be done either by testing the parents in advance or doing a blood test on your puppy before you take it home. A quality dog breeder will do everything in their power to produce only the highest quality offspring and paying attention to these important details should help you greatly in deciding where to buy you next puppy and removing the possibility that you will be greatly disappointed later.

 

 

TABLE

EIC: IMPLICATIONS FOR BREEDING
Clear dogs: no copies of the mutation
bred to a clear dog: 100% of pups clear
bred to a carrier: 50% of pups clear, 50% of pups carriers*
bred to an affected: 100% of pups will be carriers

Carrier dogs: one copy of the mutation
bred to a clear dog: 50% of pups clear, 50% of pups carriers*
bred to a carrier: 25% of pups clear, 50% of pups carriers, 25% of pups affected 

bred to an affected: 50% of pups carriers, 50% of pups affected

Affected dogs: two copies of the mutation (breeding is not recommended) bred to a clear dog: 100% of pups will be carriers bred to a carrier: 50% of pups carriers, 50% of pups affected bred to an affected: 100% of pups affected

*puppies from carrier matings can be tested to determine which ones are clear and which ones are carriers

 

 

 

New rules and systems were enacted at Rosewood Retrievers to ensure that this condition would never be passed down to another generation.  I am now VERY careful choosing breeding pairs to ensure a carrier is not bred to another carrier or affected dog.

Breeding dogs with EIC
Following is a breakdown of what EIC test results mean:

So when breeding you don’t want to breed two carriers together, or two affected together, or an affected to a carrier.  ALWAYS have a clear dog in the breeding. Here is what has been found through many year of research:

So the bottom line to all of this madness is to try to breed all clear puppies, and avoid breeding any affected puppies.

Bindi's Genetic testing results PDF

I have made a web page listing ALL my dogs used in my breeding program  KTL EIC,CNM, DM Results