KNOWN HEALTH ISSUES IN CURLY COATED RETRIEVERS
Caring breeders try to produce and then nurture puppies who are happy, well-socialized and can be a great family companion and/or performance dog. Part of that preparation is testing parents for known health issues. Here is a list of known health issues in curly coated retrievers.
If you are seeking a curly coated retriever puppy, ask any breeder you talk with to provide the health testing information on not only the parents of the puppy but the grandparents as well. Breeders should be able to provide written documentation of the health status of their breeding stock.
Another resource for those seeking a puppy from a breeder who cares enough to conduct appropriate health testing is the Orthopedic Foundation for Animals (the "OFA"). The OFA is a not-for-profit organization dedicated to reducing the incidence of genetic disease in companion animals and is a voluntary database used by many breeders to list health test results of breeding stock. To look up the health information on a particular dog go to the Orthopedic Foundation for Animals website at OFA.org.
The OFA database is largely composed of dogs from the U.S. although, in some breeds, some non-U.S. breeders list their dogs. Note well: if a dog is NOT listed in the OFA database, it doesn't necessarily mean the dog has not been tested. Enrollment of a dog in the database is voluntary and some breeders choose not to do so.
Check our button below for a quick tutorial on how to search the OFA website for curly coated retriever dogs and health clearances.
Exercise-Induced Collapse (EIC) is a genetic disorder. Affected dogs suffer from a loss of muscle control following periods of extreme exercise. A dog suffering an attack will often times start with a rocking type of gait and then the back legs weaken and give out. Some dogs continue to try to run or complete a retrieve, even with their back legs dragging along behind.
Many affected dogs recover from an EIC episode in 5-25 minutes but, in extreme case, some dogs have died immediately following an attack.
Some affected curlies do not exhibit symptoms. Researchers have stated dogs who get very excited about retrieving or exercise, or who may get stressed by certain methods of training, are more likely to exhibit symptoms.
Dogs often begin to show symptoms between 5 months and 3 years of age, usually around the age that more intensive training begins.
Some dogs with EIC can lead normal, complete lives. Others may have to have activities and certain types of training restricted.
EIC is a genetic, recessive disorder. That means most dogs must have two copies of the mutant gene in order to be symptomatic. Dogs with two copies of the mutation are referred to as "affected".
A dog might inherit one copy of the mutation from a parent and receive a normal gene from the other parent. These dogs, with one copy of the mutation, are referred to as "carriers" because they carry one copy of the gene. Carriers do not display any symptoms, except in case of a very few instances in Labrador retrievers.
If a dog does not inherit a mutated gene from either parent, he is called a "clear" dog.
Curly coated retrievers are not the only breed in which EIC has been discovered. Other breeds which can be affected include Bouvier Des Flanders, Labrador and Chesapeake Bay retrievers, Border Collies, Boykin Spaniels, and several more.
University of Minnesota researchers have found that about 18-19 percent of curly coated retrievers who have been tested carry both genes.
Here is the explanation from the University of Minnesota researchers regarding the mutation:
EIC is a hereditary condition, with litter mates and other related dogs commonly affected. It is inherited as an autosomal recessive trait. In 2007 the chromosomal locus (site) of the mutation causing EIC was found on chromosome 9, and the genetic mutation responsible for susceptibility to EIC was identified. This is a mutation in the gene for dynamin-1 (DNM1) that causes a change in the amount or function of the dynamin-1 protein in dogs homozygous for the mutation (E/E: affected). The scientific papers state that this mutation is "highly associated with EIC" - the wording required until experimental studies on the actual DNM1 protein function in the brain of dogs with EIC takes place.
Dynamin-1 is a protein expressed only in the brain and spinal cord where it plays a key role in repackaging synaptic vesicles containing neurotransmitters. DNM1 is not required during low level neurological stimulation, but when a heightened stimulus creates a heavy load on release of CNS neurotransmitters (as with intense exercise, a high level of excitement or perhaps increased body temperature) DNM1 is essential for sustained synaptic transmission in the brain and spinal cord. Dogs with 2 copies of the EIC mutation (E/E) are susceptible to collapse in those conditions.
For more info, visit the U of Minnesota Dynamin-1 EIC page here.
Video of EIC Collapse--Click to Play
Types of Glycogen Storage Disease (GSD) are found in several breeds. The type found in curly coated retrievers is type IIIa.
A genetic disorder, GSD can cause lethargy, exercise intolerance, collapse, and possibly liver damage in affected curlies. GSD is caused by a deficiency of glycogen debranching enzyme activity. The lack of enzymatic activity leads to an excess of glycogen in the liver and skeletal muscles and can lead to muscle weakness and atrophy. The liver can become enlarged when the amount of debranching enzyme is reduced.
Affected dogs experience episodic hypoglycemia, and liver and muscle disease evidenced by abnormal leakage of liver and muscle enzymes into plasma.
Like EIC, GSD is believed to be an autosomal recessive, meaning a curly must inherit a mutant gene from each parent to be affected.
To read more about GSD in curly coated retrievers, visit Dr. John Fyfe's page at the University of Michigan State HERE. Dr. Fyfe is the researcher responsible for discovering the mutation in curlies.
If you are interested in having your curly tested for GSD by Dr. Fyfe, clicking on the following PDF will give you information on how to collect cheek swabs, where to send them, a form to fill out, and the cost.
There are several other places to obtain genetic testing for curly coated retrievers. Visit our laboratories for genetic testing page HERE.
Many dog breeds have various types of heart issues, some inherited, some acquired, some with unknown causes. In curly coated retrievers there have been instances of aortic stenosis, tricuspid valve dysplasia, and cardiomyopathy, among other issues.
However, unlike EIC and GSD, the inheritance mode of heart disease is unknown and, currently in most breeds, there are no genetic tests to determine whether the parents of a dog will pass along heart issues. Parents who themselves are assessed to be free of heart issues can still produce pups with heart issues--this is true in all purebred and crossbred dogs. (Researchers have identified the gene mutation responsible for subaortic stenosis (SAS) in Newfoundland dogs but that is not necessarily the mutations that causes SAS in other breeds.)
Most responsible curly breeders in the U.S. test their breeding stock for heart issues. Most cardiac health issues will cause a detectable heart murmur in a dog.
The OFA recommends heart health tests be done by boarded veterinary cardiologists with Diplomate status in either the ACVIM (American College of Veterinary Internal Medicine/Cardiology subspecialty) or the ECVIM (European College of Veterinary Internal Medicine/Cardiology subspecialty). General veterinarian practitioners can sometimes fail to detect soft heart murmurs.
John Olin's Labrador Retriever "King Buck" memorialized on a U.S. duck stamp.
Has OFA certification significantly
reduced Hip Dysplasia? One scientific study says NO.
Hip dysplasia is believed to be caused by excessive laxity in the hip joint. The hip joint consists of the ball of the femur (at the end of the rear thigh bone) fitting into the socket of the hip. If the fit of the ball into the socket is too loose or lax, the joint is somewhat unstable.
The instability causes the ball to move around excessively in the socket, causing changes to the socket bone formation. This causes cartilage destruction, scarring of tissue and bone spurs. All these changes can cause pain and more arthritic changes.
A tendency to develop hip dysplasia has long been believed to be genetic but other factors, such as growing too fast and being overweight as a puppy, are believed to contribute to development of HD. Some theorize HD is 100 percent caused by environmental factors but this theory is not currently widely accepted.
Large breeds of dogs, including many of sporting/gun dog group, are more often affected than smaller breeds. Many sighthound breeds have no incidence of HD.
The crippling aspect of hip dysplasia was what provided the impetus for the formation of the OFA in the first place. John Olin, a wealthy and avid sportsman and hunter, owner of Winchester Firearms and Ammunition, began searching for a solution when hip dysplasia began affecting the performance of some of his dogs, according to the OFA.
Olin not only hunted his dogs but was a very well-known and successful retriever field trial enthusiast. His Labrador retriever King Buck is one of the most famous field trial winners ever. Olin organized a meeting between a group of veterinarians and members of the Golden Retriever Club of America and the German Shepherd Club of American dog clubs which led to the formation of the OFA in 1966. (Please note: I am NOT implying King Buck had HD. I do not know his hip status. I included the duck stamp image for artistic/illustrative purposes only.)
OFA uses radiographic images (x-rays) to evaluate hips. Another organization, PennHip, uses three different x-rays to evaluate hips. You can access Penn Hip information at their website at http://info.antechimagingservices.com/pennhip/
PRA Cord 1
There are a number of eye diseases in dogs and Progressive Retinal Atrophy (PRA) is one of the most concerning because it can lead to blindness and there is no cure. In PRA, the photoreceptors in the eyes (the rods and cones) essentlially die off.
PRA is inherited differently in different breeds. Some Curly coated retrievers have a gene mutation causing the PRA type named Cord 1. In PRA Cord 1, cone cells in the retina degenerate. When the rods in the eye then malfunction, the dog goes blind. Average age of onset is about 5 years but it can occur earlier.
There is a test to determine if a curly coated retriever carries the PRA Cord 1 gene. Believed to be an autosomal recessive trait, a curly must inherit the mutation from both parents to be affected.
Cases of Distichiasis are occasionally encountered in curlies. In these cases, an eyelash grows from an abnormal location on the eyelid or grows in an abnormal direction. In some instances, this can cause irritation, excessive eye discharge, pain and even damage to the cornea.
In some breeds, distichiasis has been proven to be inherited but we don't know if that is true in curly coated retrievers.
Epilepsy is essentially a malfunction of the brain which causes recurring seizures. It can be a very difficult disease to deal with, can sometimes be treated, but can sometimes lead to death in dogs. Epilepsy is one of the more common diseases in dogs.
The causes of epilepsy are unknown. There is ongoing research in many, many breeds to determine if it is genetic and how it is inherited. In a few breeds, epilepsy is known to be inherited and it is suspected it is inherited in many other breeds. Thyroid gland and liver function could be a factor in epilepsy.
There is no known cure for epilepsy but treatment with various drugs helps control the seizures in many dogs. Unfortunately there are cases where the seizures cannot be controlled and the dog suffers severe brain damage.
It is likely epilepsy is a polymorphic trait, meaning it is caused by at least two genes. This will make it more difficult to find a DNA marker and finding a DNA marker in one breed doesn't mean the same genes will be the cause of epilepsy in another breed.
The number of curlies who have seizures due to idiopathic (cause unknown) epilepsy is unknown but we know it exists in the breed.
Neck patterning in the
curly coated retriever.
Hang around curly coated retriever breeders/owners long enough and you will hear talk about "patterned baldness." The discussion centers around an issue some curlies have leading to large bald patches on the throat, the backs of the thighs, and sometimes on the tail and parts of the torso.
Some believe this baldness pattern is caused by some type of follicular dysplasia or malformation of the hair follicles. Follicular dysplasia is found in a number of breeds, including Irish Water Spaniels and Portuguese Water Dogs, two breeds which may share some common ancestors with the curly coated retriever.
Follicular dysplasia has been determined to be an autoimmune problem in some breeds. In the 1980's a long-time, experienced curly breeder had a curly necropsied after the dog died. The curly in question had one of the most severe patterned baldness cases ever seen. When the veterinarian examined her post death, he found the curly's adrenal gland was so shriveled to be essentially non-existent.
In this picture, you can see the bare patch on the throat and the tail has thinning hair. Some curlies display this type of patterning as juveniles but eventually grow a normal coat. Others who pattern as juveniles do not grow back the hair and are permanently patterned.
Some will argue patterning is merely a cosmetic issue but consider the hunting dog. Curly coated retrievers were designed as hunting dogs and, as such, must be able to work in some very difficult working conditions, both on land and water. A dog who is missing large patches of insulating fur can get chilled much faster. For those who breed working curlies, or those who hunt with curlies, patterned baldness/follicular dysplasia actually impacts the health of the dog.
My own curlies have hunted in temperatures below zero Farenheit. A dog who has fur missing to the extent where there are large patches of bald skin could never be asked to work in such conditions. So, to me, patterned baldness is a health issue.
SEVERAL TYPES OF FOLLICULAR DYSPLASIA.
There are several types of follicular dysplasia in dogs. The type affecting curlies may be the same as that affecting Portuguese Water Dogs and Irish Water Spaniels but we don't know that yet.
RESEARCH AT THE UNIVERSITY OF BERN, SWITZERLAND.
Fortunately, there is a major research project being conducted right now (as of December 23, 2016) on hereditary skin diseases in animals and humans, which includes research on follicular dysplasia in curly coated retrievers.
Dr. Tosso Leeb, a genetics professor at the University of Bern, Switzerland, is in charge of the project
Here is the link to Dr. Leeb's project:
There have been some cases of craniomandibular osteopathy, commonly known as CMO, in curly coated retrievers. CMO is a bone disease in which the mandible (lower jaw) thickens, causing pain and tenderness and difficulty opening the mouth. Extra bone forms along the lower jaw and the jaw joint connecting the upper and lower jaws.
Pups usually start to display symptoms, including problems eating and chewing, at 4 to 7 months of age. They sometimes have bouts of fever.
Diagnosis is through x-rays. In some breeds, CMO is considered an inherited disease but we don't know that for certain in curlies.
If you are interested in learning more about CMO, you can read more about it at http://cal.vet.upenn.edu/projects/saortho/chapter_54/54mast.htm
Cancer is considered the biggest health threat to dogs, especially those older than 10 years. There are many types of cancer and those types are seen in almost every breed and in mixed breeds. The National Canine Cancer Foundation estimates one in three dogs get cancer.
There are many ongoing cancer research projects in dog. With so many types of cancer, I am not going to list them here. Instead I wanted to include a list of symptoms to look be on alert for. This list was provided by the National Canine Cancer Foundation.
Top ten warning signs your dog might have cancer:
Abnormal swellings that persist or continue to grow
Sores that don’t heal
Loss of appetite
Bleeding or discharge from any body opening
Difficulty eating or swallowing
Hesitation to exercise or loss of stamina
Persistent lameness or stiffness
Difficulty breathing, urinating, or defecating.