Health & Breeding
Part of every responsible breeder’s commitment to the breed, is to improve the health and lessen the incidence of genetic diseases. Although not compulsory, responsible breeders test their breeding animals,
As with most breeds of purebred dogs, there are certain diseases that are known for the breed to be predisposed to, and the Bull Terrier breed is no exception, the following are known hereditary problems in the breed. This of course does not mean that there are not other problems in the breed, it just means that these are the ones being worked on first.
The following have been designated as known hereditary health problems affecting the Bull Terrier breeds:
* Deafness (Unilateral & Bilateral)
* Heart Disease
* Nephritis* Polycystic Kidney Disease (PKD)
* Luxating Patella
DEAFNESS
Deafness can be detected as early as four weeks of age. The only conclusive test for differentiating between normal and abnormal hearing is the BAER test ( Brainstem Auditory Evoked Response Potential). In this, the dog has three fine electrodes inserted just under the skin on appropriate parts of the head, and an earphone is used to make clicks of known volume in one ear while the other is covered. Testing can be done as early as 5 to 6 weeks of age. Only one test should be needed for verification of hearing status.
There are three deafness classifications:
* Normal bilateral hearing
* Unilateral deaf (deaf in one ear), and
* Bilaterally deafness (deaf in both ears)
It is important to detect if a puppy can hear in both ears, because if dogs deaf in one ear are bred from the incidence of deafness in the breed is increased. The cells which are responsible for deafness are also involved with the inheritance of coat colour. It is primarily white dogs (in many breeds) which suffer from deafness, but coloured Bull Terriers can be deaf, even solid coloured ones have been known to be deaf.
Veterinary advice is to remove unilaterally deaf dogs from the breeding stock (suitable for pets only). Most responsible breeders euthanase totally deaf puppies because dogs are controlled by tone of voice - which is impossible with a deaf dog.
HEART DISEASE
The issue of heart disease in Bull Terriers is primarily seen in the form of congenital heart disease. The two forms commonly seen are Mitral Dysplasia and Sub-Aortic Stenosis.
The commonest is Mitral Dysplasia, in which the valve between two of the heart chambers does not close properly, so when the heart tries to send blood into the arterial system, some of it leaks back. In an attempt to send enough blood round the body the heart overworks and may enlarge. If the mitral valve leaks badly this may lead to heart failure even in young dogs.
The other frequent problem is Sub-Aortic Stenosis. In this condition the main artery from the heart, the aorta, is narrowed just where it leaves the heart. To push enough blood past this constriction the heart has to work harder, again possibly leading to heart failure. In a normal heart the valves opening and closing and the blood flows produce characteristic sounds, if a valve is faulty or a blood vessel constricted, the abnormal sounds produced are called heart murmurs.
The severity of these is graded from 1 (mild) to 6 (very serious). Detection and grading of heart murmurs should be entrusted to a veterinary cardiologist - a veterinary surgeon with special training leading to the Diploma or Certificate in Veterinary Cardiology. Although an ordinary veterinary surgeon can detect heart murmurs from grade 3 upwards, they cannot reliably find lower grade heart murmurs. Yet such murmurs are undesirable in breeding stock because heart problems are inherited. As there are several different causes of heart disease the modes of inheritance have yet to be determined, the only advice which can be given is to breed only from heart murmur free parents.
There are several tests veterinarians can perform to screen for these conditions which include Auscultation with a stethoscope, x-ray of the chest, ECG (electrocardiograph) to measure the heart's electrical activity and a cardiac ultrasound or echocardiography. Heart conditions are graded 1 – 6.It is advisable that all breeding stock should be tested for this inherited problem and any dog found to have the disease, should be removed from any breeding program
KIDNEY DISEASE
Inherited Kidney Disease (IKD) has been reported in many breeds of dogs including the Bull Terrier and Miniature Bull Terrier as well as in people.
There are many different types of kidney disease, inherited (or genetic) faults being only one cause. Infections, poisons, some drugs, non-genetic cancers, liver, pancreas, uterine, heart disease or many other diseases can all cause kidney diseases.
The inherited conditions in Bull Terriers can occur in very young (less than six months) middle-aged or very old animals. Some dogs can be 10 years old plus and have the faulty gene in their makeup, pass it on to some of their pups, and may appear normal to their owners. These animals may live to a ripe old age with no one suspecting they have the diseases or have passed it on to their pups.
Signs of kidney failure that are common to both types of IKD and to other causes of kidney failure include the following:
* poor appetite
* dullness or lethargy
* weight loss or stunted growth
* poor hair coat
* vomiting/diarrhoea
* foul breath and mouth ulcers
* muscle twitching and convulsions
* drinking excess water and passing too much urine – often noticed in an increase in the urine passed overnight.
* pale gums (anaemia)
* dehydration (sticky dry gums)
There are two types of kidney diseases in Bull Terriers
The first type is polycystic kidney disease (PKD) where the kidneys contain fluid filled cysts (or balls of fluid) which can be seen by looking at the kidney, for example by using an ultrasound machine, as black "holes" inside the kidneys. At what age this commonly is first detectable is unknown. While it is possible to detect the defect in some dogs as puppies, it may be that in animals it is not obvious until the dog is much older. In this disease a urine test will not pick all affected dogs, so an ultrasound examination is ideal.
PKD is an inherited kidney disease, thought to be inherited in an autosomal dominant fashion. In PKD, the kidneys contain fluid filled cysts.
The test for diagnosing this disease is an ultrasound examination on the dog and the test performed by a specialised veterinarian.
It is advisable that all breeding stock should be tested for this inherited problem and any dog found to have the disease, should be removed from any breeding program.
The second condition is nephritis where the kidneys may look fairly normal until a biopsy (or small piece of tissue taken from a live animal) is examined under a microscope. It is not possible to diagnose this disease on the basis of only an ultrasound examination. A urine test or kidney biopsy are the best tests for this disease.
Nephritis is an inherited kidney disease. It is understood to be inherited in an autosomal dominant fashion (which means that only one parent has to have the fault for half the litter to be affected)
A urine test - a U P/C test (Urine Protein Creatinine ratio) or a kidney biopsy are the two tests for diagnosis of this disease.
It is advisable that all breeding stock should be tested for this inherited problem and any dog found to have the disease, should be removed from any breeding program.
Both conditions are thought to be inherited by an autosomal dominant fashion, which means that only one parent has to have the fault for half the litter to be affected. If both parents have the fault three-quarters or more of the pups may be affected.
Because of the way these conditions are inherited, there is no point in condemning whole kennels or blood lines. As an affected dog may produce many unaffected pups and these animals do not have the faulty gene/s, these animals are fine to breed with as long as they are regularly tested. They have the virtues present in the lines but without the ‘taint’ of the faulty gene/s.It is advisable that all breeding stock should be tested for this inherited problem and any dog found to have the disease, should be removed from any breeding program.
PATELLA LUXATION
The patella is a small bone sliding in a groove in the stifle joint - equivalent to the kneecap in the human knee. If the groove is too shallow the patella may slip sideways out of the groove, causing the dog to limp, until it slips back - often seen as a limp, a skip and hop followed by normal movement. The patella may slip out of its groove easily or only occasionally. In a badly affected dog the joint is painful and becomes arthritic. The mode of inheritance is polygenic (controlled by several or many genes) and can only be combated by breeding from unaffected parents. A veterinary surgeon can test the joint by feeling how firmly seated the patella is in its groove.
In simplest terms, this is when the kneecap slips out of place. The range can be mild to severe and depends on how shallow the groove is. The mode of inheritance is understood to be recessive.
It is wise to limit your puppy/adolescent Bull Terrier's activity (i.e. don't allow them to jump from heights etc) to help reduce undue strain on young joints.It is advisable that all breeding stock should be tested for this inherited problem and any dog found to have the disease, should be removed from any breeding program
For further detailed articles about disease please follow the below link to the National Bull Terrier Council of Australia.
http://www.nbtca.com/breedinghealth.asp
Contact Details
Contact Details
BTCWA IncPerth, WA, Australia
Phone : 0414700575
Email : secretary@btcwa.asn.au