Your Trusted Expert in Breeding and Maintaining Healthy Portuguese Water Dogs

Guidance in Choosing a Breeder:

You should never adopt a PWD puppy from a breeder who cannot show you written documentation of the pup’s parents’ GM1 status. GM1 gangliosidosis (Portuguese water dog type) is a lysosomal storage disease that typically manifests in affected puppies between 2 and 6 months of age. Affected puppies have problems with vision, gait, balance, bone growth, and weight loss. Affected puppies usually die within a year. GM1 is an autosomal recessive trait. This means that a puppy must have two alleles of the affected gene, one from each parent, to exhibit the disease. If a puppy has only one copy of the affected gene, they are considered a “carrier” but will not have any signs of the disease. As an adopter of a new puppy, you should make sure that no more than one parent of the litter was a carrier. In other words, at least one of the parents must be “clear.” If both parents are clear, then all of the puppies will be clear. If one of the parents is a carrier, then likely half of the puppies will be carriers. This means that they will be healthy, but if they are bred, then they must be very careful to make sure that the dogs they are bred to are clear and not carriers. There are many laboratories that can test for the GM1 gene in your prospective puppy, if the status of the parents is unknown. Please contact our office for more guidance.

PRA-prcd causes the degeneration of the rods and cones of the retina. Night blindness and loss of peripheral vision happens first, but the disease eventually progresses to full blindness in most cases. Onset is usually later in life, between 3 and 5 years of age. Because of the later onset, it is possible that untested parents with the genetic condition could be bred before they themselves show any signs of disease, and pass it on to puppies. Because of this potentiality, it is of paramount important that all dogs are tested prior to breeding. EOPRA is another variant of PRA detected in PWD which sets in between 2 and 3 years of age. DNA tests for both types of PRA are available and, like GM1, are both autosomal recessive traits. This means that at least one parent must be clear of the mutated alleles in order for all puppies to be unaffected. In other words, it is OK if one parent is a carrier (has only one copy of a mutated allele), so long as the other parent is completely clear. If one parent is a carrier, then it is likely that some of the puppies will also be carriers. Single-allele carriers of autosomal recessive diseases do not exhibit signs of the disease, and this is the case with both early and late-onset PRA. You can confidently adopt a puppy that is a carrier (just don’t breed it to another carrier).

MO is a condition where puppies are born with abnormally small and ultimately dysfunctional eyes. Stunted growth is also associated with the condition. It has been shown to also be an autosomal recessive trait. Breeding animals should have a DNA test prior to breeding. Carrier animals can be bred to clear animals, just not to each other. You would probably know if a puppy you are considering for adoption has MO because it would have very small eyes and stunted growth.

Most types of dilated cardiomyopathy (DCM) happen in adult animals and are often preceded by clinical signs including lethargy, coughing, labored breathing, and collapse. In PWD, a juvenile form of DCM exists which manifests when they are 2 weeks to 6 months old. The progression of the disease is so rapid that death often happens before any other clinical signs are recognized. As with other diseases on this page, JDCM in PWD is an autosomal recessive trait and can be tested for using a genetic test. Carrier dogs may be bred to clear dogs, but should never be bred to another carrier dog. As a prospective puppy owner, you should make sure that at least one parent of the litter was clear of mutated JDCM alleles.

In addition to the genetic tests described above, it is important that both sire and dam have had a companion animal eye registry (CAER) exam in the past 12 months. There are times that a human, board-certified veterinary ophthalmologist will detect abnormalities in the eyes that are not represented by the limited genetic testing we have available. You should request these results from each parent and review them.

Hip and elbow dysplasia are orthopedic conditions that can be debilitating for dogs by making every step they take painful and difficult. The conditions are caused because the bones of the hip or elbow joints are not formed and seated appropriately. Eventually, they wear away at the cartilage and bone will rub on bone, which is painful. Signs that a dog will eventually become dysplastic can be detected early in life through radiographs (x-rays). Since the predilection for these conditions is genetic, breeding affected dogs together increases the risk that the resultant puppies will have bad hips or elbows, often necessitating expensive and difficult surgical corrections at some point in their lives. It is recommended that dogs with poor conformation not be bred and dogs with moderate changes be bred to dogs with excellent joints. The sire and dam of your prospective puppy should have been tested minimally for hip dysplasia and (ideally) for elbow dysplasia and those records should be available to you.

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