The goal of the NTCA Health Committee is to identify health concerns and research opportunities most relevant to Norwich Terriers, organize health clinics and research studies, and disseminate health related information to the NTCA membership. NTCA encourages all members to be aware of the health issues that affect Norwich Terriers, and breeders are expected to adhere to responsible breeding practices to reduce or eliminate hereditary problems. This section provides an overview of the health conditions that are of most concern, and a list of recommended health screening tests to guide breeders.
Norwich Terrier Health Conditions
Upper Airway Syndrome (UAS) is a complex respiratory condition that is quite variable in its presentation in the Norwich Terrier. Symptoms range from noisy breathing to severe distress, and even death if not treated. This condition affects the larynx, which is the structure that controls the amount of air that enters into the trachea and lungs. If the larynx is obstructed in any way, respiratory distress will ensue. The true prevalence of the condition is unknown because even dogs with no apparent symptoms may be affected. Because the condition appears breed-specific a genetic basis seems likely. It is our most pressing health concern. Please see NTUAS Health Study for information about our study of Norwich Terrier Upper Airway Syndrome currently underway.
Neurologic disorders encompass diseases of the brain, spine and the nerves that connect them. Structural, biochemical or electrical abnormalities can result in a range of symptoms including paralysis, muscle weakness or cramping/stiffness, poor coordination or movement disorders, confusion, altered levels of consciousness and seizures.
Epilepsy is the condition of recurrent seizures and has many causes including toxins, metabolic conditions and primary conditions such as a brain tumor. Idiopathic or common epilepsy refers to an unknown cause and is believed to have a genetic basis. Any breed can have epilepsy but some breeds seem to have a higher incidence. Because epilepsy is not a single disease, its prevalence in dogs is not known, however estimates of up to 5% of the canine population are cited. Little is known about prevalence in Norwich Terriers. A recent white paper, Understanding Canine Epilepsy (2014) by the Canine Health Foundation provides an overview. Accurate diagnosis is important in order to determine the most appropriate treatment.
Degenerative Myelopathy (DM) is a neurological disorder that is an incurable, progressive disease of the canine spinal cord causing progressive paralysis. DM is seen most frequently in the German shepherd dog, Pembroke Welsh Corgi, and Boxer, with onset typically after the age of 7 years. A gene has been identified that is associated with a major increase in risk of the disease. This gene has been reported in several Norwich Terriers, but has never been expressed (carrier, but not affected).
Hip dysplasia is one of the most common skeletal diseases seen in dogs. Malformation of the hip joint causes gradual deterioration, leading to loss of function. Symptoms depend on the degree of joint laxity, and in later disease are related to joint inflammation, degeneration and osteoarthritis. Symptoms include decreased activity or reluctance to run or climb stairs, bunny-hopping or swaying gait, and hind-limb lameness. Hip dysplasia is caused by both genetic and environmental factors.
The Orthopedic Foundation for Animals (OFA) statistics through 2015 show 85.5% normal (of 1,077 evaluations) for Norwich Terriers.
Patellar luxation is when the patellar (kneecap) pops out of its normal anatomic position in the groove of the femur. This can occur in one (unilateral) or both (bilateral) stifle joints. Patellar luxation may stem from a traumatic injury to the knee, causing sudden lameness, however, there is evidence that the condition is at least in part genetic. It is a common orthopedic condition in dogs, especially toy breeds.
The Orthopedic Foundation for Animals (OFA) statistics through 2015 show 94.5% normal (of 925 evaluations) for Norwich Terriers.
Dogs can have various eye diseases that may cause discomfort and vision loss or impairment. Norwich Terriers are not known to have specific predispositions to eye disease.
The Orthopedic Foundation for Animals (OFA) statistics through 2015 show 99% normal (of 415 evaluations) for Norwich Terriers.
Primary lens luxation
Primary lens luxation (PLL) is a painful, genetic eye disorder that can lead to blindness, reported in more than 45 breeds and more common in terriers. It is a late-onset disease, typically presenting between 4 and 8 years of age. A DNA test is now available and breeders can test dogs to determine their PLL status (normal, carrier, affected) prior to breeding.
Periodontal disease is a common under-treated clinical condition in adult dogs, that can damage the heart, liver, and kidneys as the dog ages. Bacteria in the mouth cause formation of plaque which sticks to the surface of the teeth and is hardened by minerals in the saliva to form tartar. Periodontal disease develops as plaque and tartar spread under the gum line, causing inflammation of the gum, and loss of bone and soft tissue around the teeth. Because Norwich are prone to develop plaque and tartar, diligent dental care is essential.
Reproductive Problems and Challenges
Breeding Norwich Terriers is not for the faint-hearted. Reproductive problems are common and include failure to conceive, resorption of puppies, difficult whelping and frequent need for caesarian section. Litter size averages 3 to 4 puppies and puppies sometimes require supportive intervention, such as tube-feeding a weak puppy, and neonate mortality is much too high.