In spite of the efforts of responsible Jack Russell breeders to rid the breed of all genetic problems, some disorders still pop up from time to time. This article shows you discusses some of the more common problems found in the breed. Please understand, however, that this is not an all-inclusive list, and it shouldn't be used as a guide to diagnosis. Always seek your vet's advice for any symptom or problem you may encounter in your Jack Russell Terrier (JRT).
- Cardiomyopathy: Cardiomyopathy, an abnormality of the heart muscle, can result in lung edema (water in the lung), weakness during exercise, and sudden death. This defect is difficult for the average owner to detect, but if you notice your JRT having trouble after a walk or a run in the park or if you hear her wheezing when she breathes, explore this possibility.
- Cerebellar ataxia: Cerebellar ataxia is a neurological disorder resulting from degeneration of the cerebellum's cortex. The degeneration can progress steadily and cause a stagger in the dog's gait. If your terrier appears wobbly on her feet or disoriented from time to time, this disorder could be the cause.
- Cryptochidism: Cryptorchidism is the failure of one or both testicles to descend into the scrotum. The testicle is retained in the abdomen or inguinal area, and it may slide in and out of the scrotum. You can easily detect this problem because your male terrier will appear to have only one testicle in the scrotum or will alternately have two and then one, depending on the day. Although this isn't a life-threatening problem, it is best to neuter a terrier born with cryptorchidism. A cryptorchid dog may be more prone to cancer.
- Hernias: Hernias occur when a one of the dog's organs or tissues protrudes through a body wall. The most common of these are the inguinal hernia and the umbilical hernia. These occur when a portion of the intestine falls through the scrotal opening or through the umbilical opening. You will notice a bulge in the dog's stomach or scrotum that looks like a growth. Take your dog to a veterinarian immediately.
- High toes: The term high toes or short toes applies to a condition in which the toes of the front feet are shorter than normal in a full-grown terrier, giving the appearance of toes that don't touch the ground. This occurs primarily on the front feet, but it has been seen on hind feet, as well. Although not a debilitating defect, it is considered a breeding fault.
- Hydrocephaly: Hydrocephaly results from an accumulation of fluid in the brain, and it causes the brain to degenerate. The afflicted dog often becomes disoriented or runs into objects while walking. Sadly, dogs with this condition don't usually live long. For those who survive, treatment often is ineffective. Hydrocephalic dogs often are euthanized.
- Legg-Calve-Perthes disease: Legg-Calve-Perthes (also called Legg-Calve) disease is a septic necrosis, or degeneration, of the head of the femur (the thigh bone). It usually doesn't manifest itself until a puppy is at least six months old, and it can result in progressive rear-leg lameness. It primarily affects small breeds. If you notice that one of your terrier's legs looks different than the other three or that one is particularly susceptible to becoming sore, this disease could be causing the problem.
- Lens luxation: Lens luxation is a fairly common inherited disease of the eye in which one or both lenses become partially or completed dislocated from their normal location behind the cornea. In the case of complete dislocation, the lens will be painful and the eye will look red or opaque. Lens luxation, if left untreated, can develop into. The condition usually manifests itself later in life and should be treated as soon as it is diagnosed to prevent blindness. This condition seems to be relatively common among terriers and particularly among Jack Russell Terriers.
- Patent Ductus Arteriosus: Patent Ductus Arteriosus is caused by the failure of the fetal vessel between the aorta and the pulmonary artery to close at birth, causing heart murmurs, weakness, and even death. Special care must be taken of dogs with this condition because they are susceptible to heart failure when exercised even moderately. Surgery for this disorder can be quite effective, especially if performed when the dog is young. This is a problem that can't be diagnosed unless the dog is examined by a veterinarian.
- Progressive neuronal abiotrophy: Progressive neuronal abiotrophy (or ataxia) causes tremors and a lack of coordination in dogs and is caused by degeneration of the cerebellum's cortex responsible for coordinating movements. As a result, a dog develops a staggering gait and becomes unable to stand or even eat.
- Von Willebrand's disease: Von Willebrand's disease, also referred to as vWD, is a common, inherited bleeding disorder that manifests itself through abnormal platelet function. Symptoms include ongoing bleeding of the gums and nose, bloody urine, prolonged bleeding during estrus or after the birth of a litter, and excessive bleeding after surgery or by a slight nick while trimming your Jack Russell's nails. It is caused by an insufficient von Willebrand factor, a blood protein that binds platelets to blood vessels.
- Continued bleeding in humans is nothing to laugh at, and it is no laughing matter in the case of your Jack Russell Terrier, either. If you notice that your JRT has a tendency to bleed easily or that bleeding continues for a significant amount of time after a small nick or cut, notify your veterinarian and ask for his or her advice. Mention the fact that your terrier bleeds easily and that the bleeding is difficult to stop.
- The disease usually attacks purebred dogs, although mixed breeds also can be affected. The good news is that it isn't as common in JRTs as in other breeds. The bad news is that it can crop up from time to time, and it is serious enough to warrant testing if you suspect your terrier may be a victim. It is important to test for Von Willebrand's disease early on, and many experienced and responsible breeders have their breeding stock tested prior to breeding. Breeders often advertise their litters as having been tested for the disease.
Although this list certainly is daunting, rest assured that there are far fewer occurrences of these disorders and diseases in JRTs than in many other breeds. If all of this medical mumbo-jumbo makes your head swim, just follow some simple advice: If you notice any of these symptoms in your dog or if you suspect something isn't right, notify your vet right away. Some disorders can be managed and treated; others are irreversible, and you need to make an informed decision regarding your dog's future.von Willebrand's disease.