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         The Miniature Bull Terrier or "mini bull" is a relatively healthy breed however as with all pedigree dogs there are known inherited conditions that we have to keep a tab on to ensure nothing becomes widespread and therefore threaten the welfare of this small breed.

Sadly there are still too many people breeding mini bulls who are not completing the recommended health tests first. Puppy buyers hold the power for health-testing by ensuring they only buy puppies from health-tested parents – this will help weed out those who don’t as their market will dry up forcing them to either test or give up!

We do ask that people report all health conditions to the Health Co-ordinator, even if anonymously, so a register of problems can be kept and compared yearly. This will help us keep track of health problems and note if anything is becoming more prevalent. Don’t let those with problems suffer in vain, let them help the breed and its future.

The main conditions that we need to test for and keep tabs on how they are affecting the breed are as follows (note the word ‘dog’ is used throughout but relates to both male and females.


Primary Lens Luxation (PLL)

A painful eye condition which should become a thing of the past after the Animal Health Trust (AHT) found the gene mutation and introduced a DNA test around 4 years ago. All breeding animals and puppies should hold a valid DNA certificate (stating Clear or Carrier) or certified ‘clear by parentage’ on their KC paperwork. It is still acceptable to breed from Carrier dog’s providing the potential mate is Clear. Clear x Carrier can produce both Clear and Carrier puppies therefore the whole litter should be DNA tested prior to sale. Clear x Clear can only produce Clear puppies therefore their KC paperwork should state ‘clear by parentage’ or they should hold a clear DNA certificate.This DNA test can be carried out on puppies after they have been weaned as well as adult dogs. This DNA test is only required once in the dog’s lifetime. At present we still recommend yearly eye checks with an ophthalmologist to ensure there are no other underlying eye conditions previously hidden by PLL.


Kidney Disease

There are two different types of kidney disease to be screened for. Hereditary Nephritis (HN) and Polycystic Kidney Disease (PKD). Both are known as silent killers as owners rarely notice the few signs/symptoms until the kidneys are in complete failure.HN is screened for using the Urine Protein Creatinine (UPC) test which gives a final ratio. Anything above 0.3 can indicate early kidney failure and should be investigated. This ratio threshold (0.3) is unique to bull terriers/mini bull terriers (other breeds use 0.5) so please ensure you inform your vet and see the paper work of the lab results. A copy of the lab report should be kept for proof. Dogs should be tested from 1 year of age. This screening test should be carried out yearly.PKD is screened for by ultrasound of the kidneys where a clear picture can be seen by the vet to ensure no cysts are present. At least 3 cysts across the kidneys should be seen for PKD to be diagnosed along with a parent or sibling having the same problem. A letter/certificate from your vet stating ‘no cysts found’ should be kept for proof. Dogs should be tested from 1 year of age. This test is only required once in an adult dog’s life.


Heart Disease

There are a number of different heart conditions that can affect dogs however the main two known in the mini bull are Mitral Valve Disease (MVD) and Aortic Stenosis (AS). These conditions affect different valves in the heart making it difficult for blood to pass through or causing ‘back flows’. Dogs should be heart checked by qualified cardiologists (Vets often miss low grade murmurs) using special equipment to detect heart murmurs. A minimum expectation is that the heart is listened to using auscultation (a special stethoscope able to hear even low grade murmurs) however the preferred method would be auscultation and ECG of the heart or full Doppler testing. A letter/certificate from the vet should be kept showing no murmurs present. Animals should be tested from 1 year of age. Auscultation should be carried out yearly Doppler testing, being more accurate, can be carried out 2 yearly



This is normally associated more with white dogs however it has been known for coloured dogs to be affected too. Dogs can be either be deaf in one ear (unilateral deafness) or deaf in both ears (bilateral deafness). It is difficult to notice deafness in young puppies as they tend to react to vibrations or follow their litter mates or those deaf in one ear who can react normally. A BAER (Brainstem Auditory Evoked Response) carried out by a specialist trained to use the machine is the only way to know for certain. Small probes are placed on the puppy/dog and a headphone over the ear emitting a clicking noise is used while the computer records the brains response. This is a non-invasive test that does not cause any pain or harm to the puppy/dog. On some occasions adult dogs will need to be lightly sedated to keep them still but puppies are fine awake. This test can be carried out on puppies from 5 weeks old and any age after that. This test is only required once in the dog’s lifetime. A copy of the report from the specialist should be kept for proof.


Patella Luxation

The patella is more commonly known as the knee-cap can luxate (slip out of place). This can be very slight and no obvious signs of limping are seen or more serve and an obvious limp noticed. This can be a painful condition for the dog and may cause constant pain. In serve cases an operation to fix the joint where the patella it attached will be required. If required Kennel Club must be notified and their permission obtained before the dog can be exhibited. A competent vet can manipulate the dog’s legs to check for signs of slipping patella. Dog should be checked for this condition should any symptoms arise.



Canine Herpes

The virus Canine herpesvirus (CHV-1) is a virus that has been largely ignored for many years. However, it is becoming increasingly clear that the virus causes many more problems than was first thought. Like all herpes viruses, CHV is highly infectious, and a recent study showed that more than 80% of dogs in England have been exposed to the virus at some time in their lives

The problem

For most dogs CHV is not thought to cause any significant problem and so for a long time is has largely been ignored by both breeders and vets. However, it is now clear that CHV can be a significant cause of death in young puppies, and also smaller litter size and weight.

The unborn puppyCHV attacks the placenta of the mother, starving the foetus of nutrients. This can lead to abortion, stillbirth or re-absorption of the foetus (seen by the breeder as infertility).

The newborn puppyIf the puppy is infected before birth and survives, it may be underweight at birth and have a weakened immune system, making it vulnerable to early puppyhood infections. If the puppy is infected soon after birth, CHV is known to be one of the factors in "fading puppy syndrome", in which the pup fails to suckle, loses weight and fades away despite intensive care.

The adult dogin the dog, CHV can cause painful lesions on the genitals. In the bitch, there may not be any external signs, but the bitch seems infertile or gives birth to undersize and weak litters. In both males and females, CHV is also known to be a cause of kennel cough.

The problem

There is no cure for an animal that has CHV - infection is probably lifelong and can flare up repeatedly during periods of stress. Antiviral drugs do not appear to be effective and are very expensive


A new vaccine has just been launched in the UK, this cannot prevent infection but if given during pregnancy it has been shown to significantly improve fertility rates and reduce early puppy death.Even bitches that already have the virus can be vaccinated.The vaccine is available from veterinary surgeons now and for more information about this new vaccine, contact your local veterinary surgeon or log on to





More detailed information on the above problems can be provided, please contact the Health Officer for further information, support or advice.
This of course is not a definitive list of conditions dogs can suffer from and yearly health checks should be carried out by your vet to ensure general good health is maintained throughout your dog’s life.


(More information about health concerns for the Miniature Bull Terrier breed can be found on the Miniature Bull Terrier Club of America website - . The information above was provided by this website and all credits and rights are reserved to them. Thank you!)

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