Retrievers and greyhounds (Proceedings)


Retrievers and greyhounds (Proceedings)

May 01, 2011


Retrievers can have work-related conditions or they can have genetic conditions. A common work-related problem is related to overheating. A medical condition seen in Labrador Retrievers is Exercise-induced Collapse.

Overheating is also called hyperthermia, heat prostration, and heat stroke. There is an inability of the body to regulate its temperature. The heat produced by the body is greater than the body's heat dissipation. The causes of hyperthermia include lack of conditioning, lack of acclimatization, high humidity, high temperature, too much exercise too soon, obesity, and previous overheating episodes. The clinical signs of overheating are panting, extreme hyperventilation, hypersalivation, altered mentation (glassy eyed), ataxia, muscle weakness, vomiting, diarrhea, weakness and collapse. All of the body's systems can be damaged. Other problems associated with hyperthermia are disseminated intravascular coagulation (DIC), adult respiratory distress syndrome (ARDS) severe electrolyte abnormalities. Basically the internal tissues can be cooked.

Overheating in the field is a scary situation, and time is of the essence. It is best to educate the clients that have athletic or working dogs on how to handle dogs with hyperthermia. They must understand that the most important thing to do is to get to the veterinarian. The longer the body is exposed to high temperatures the more damage is done. Too many dogs have suffered brain damage or have died because of futile attempts to treat in the field. The cause of death wasn't the initial heat exhaustion itself, but the secondary damage to the kidneys resulting in kidney failure. In a lot of these cases the dog would have been much better served if the top priority had been to initiate the trip to the veterinarian. The cooling down treatments could have been performed during the trip to the veterinarian and therapy could have been provided at an earlier stage of the emergency. Immediate treatment for this condition is a cool water bath or spray, ice applied to the abdomen, and/or blow a vehicle air conditioner or fan on the dog's body. Cool the body to around 103 degrees and the stop. If cooling measures are continued after this, the body's temperature will continue to drop. This will result in a hypothermic state.

Once the veterinarian receives the case, start to cool the dog down, insert an intravenous (IV) catheter and begin to determine the dog's status. Corticosteroids (dexamethasone) given IV at a shock dose of 1 mg per pound have shown to be of benefit in most cases. It is important to monitor the kidney function of the dog. It is common for a dog to recover from the hyperthermic event and then succumb to kidney failure.

Medical conditions caused by exercise are now starting to be identified. It is not clear if we are now just starting to identify problems that have been there fro a long time or if these conditions are now starting to appear because the work level of dogs has recently started to increase. Currently the most common example of an exercise induced medical problem is in Labrador Retrievers. Exercise induced collapse (EIC) is a condition in certain Labrador retrievers where after about 5-15 minutes of exercise these dogs start to loose control of their rear limbs. Some of the dogs will progress to the point that their body will totally collapse. There have been instances where the dog will get so bad that death is the end result. In most cases, if the handler stops the work at the first sign of an episode and then rests the dog for 10 – 15 minutes, the dog will return to normal. At this time there is no definitive treatment for this condition. It is very important that the veterinary clinician rule out other medical conditions before actually diagnosing a Labrador Retriever with this problem because it has recently been shown that other medical conditions that can be treated will exhibit clinical signs similar to EIC. Two other conditions that have been reported to occur on a rare occasion are Exercise induced seizures and Phosphofructokinase deficiency.