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Southern Border Collie Club - Working For Collies
On the whole the Border Collie is a healthy breed – but as with any other breed there are some medical problems which may occur from time to time, some hereditary and some not. Experienced, responsible breeders will make every effort to breed only from well tested, healthy stock and to carry out all necessary tests to ensure that the pups are healthy. It should be pointed out that although the following section covering various diseases is comprehensive this is in order to explain what MAY occur in a minority of dogs – not to say that these diseases are common in the breed. It also explains the importance of not breeding from affected dogs and therefore the importance of breeders using every test available to ensure the health of their breeding stock and their puppies.
CEA – COLLIE EYE ANOMALY:
The more accurate name for it is Choroid Hypoplasia (CH) – the choroid is a layer of tissue under the retina, which in CEA can be seen to have underdeveloped, thin, almost transparent patches, in one or both eyes. Mildly affected dogs may have perfectly normal vision, but if bred from, can produce severely affected puppies. Severely affected dogs suffer a serious loss of vision and many have colobomas - holes or pits in the retina. At worst, severe CEA cases suffer intraocular haemorrhage, detachment of the retina, and blindness. CEA is inherited via an autosomal recessive gene, but thanks to the recent development of the gene test by OptiGen in the USA, producing affected puppies can be avoided in future by selective breeding.
OptiGen 20/20 Clinics – a 20% discount scheme where a blood drawing session is arranged for 20 or more dogs and the samples flown next day to New York. Visit
OptiGen's website for more information. A further 5% discount is available to owners who register and pay
OptiGen online by credit card. Results come back showing dogs to be either Normal, Carrier or Affected. Dogs with a Normal result receive a Certificate of status.
An OptiGen 20/20 clinic (CEA & CL testing) is held in the club's geographical area every February and September - for full details contact the organiser Mrs Val Tiller directly. Separate samples can also be sent from these clinics to Alan Wilton for TNS testing. OptiGen prefer dogs to be permanently identifiable, and microchipping is available at Val's clinics. The Border Collie Breed Council also hold 20/20 clinics in the Midlands in early May each year - for further details as they become available please check the
OptiGen site.
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CL – CEROID LIPOFUSCINOSIS:
An hereditary, fatal disease, similar to Batten’s Disease in humans, CL is also called Storage Disease - an accumulation of toxins builds up in the brain, owing to an enzyme abnormality, which prevents the dog from disposing of them normally. Symptoms appear from around 15 months of age and gradually worsen, beginning with abnormal behaviour, such as fear of familiar people and objects, unsteadiness and abnormal gait, and progressing ultimately to dementia, disorientation, loss of bowel/bladder control, hyperactivity, rage and mania. As there is no cure, the only course is euthanasia. Confirmation of CL is post mortem. The recent development of the gene test to identify Carriers means selective breeding can eradicate this disease.
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TNS – TRAPPED NEUTROPHIL SYNDROME:
An hereditary disease where the bone marrow produces white cells (known as neutrophils) but is unable to release them into the bloodstream - as a result affected puppies have an impaired immune system and will eventually die from infections which they cannot fight.
Research continues into TNS and testing is now available. For further details please read
this article on the website of Wessex Border Collie Club.
You will find the latest report (with update) by Dr Alan Wilton HERE & a brief bio of research scholar Jeremy Shearman
HERE.
TNS Bulletin from the PBHF ~ June 5th 2007
Following the Quarterly TNS report received from Alan Wilton at the end of May, the PBHF has agreed to release a further Aus$6000 towards ongoing research.
The good news is that Alan & Jeremy have identified the TNS mutation, the bad news is that their application for funding of this research through the Australian Research Council has not been successful.
Consequently they will have to rely on continued donations from Border Collie breeders and enthusiasts around the world to fund further research in Border Collies and other breeds.
We have available for download the TNS sampling instructions & the consent form.
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November 2007 KENNEL CLUB BULLETINS:
The Kennel Club has announced new DNA Testing Schemes For Border Collies for Collie Eye Anomaly/Choroidal Hypoplasia (CEA/CH) and Ceroid Lipofuscinosis (CL) and for Trapped Neutrophil Syndrome (TNS), whereby test results can be added to registration documents.
Read the KC Bulletins here.
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PRA – PROGRESSIVE RETINAL ATROPHY:
PRA is a degenerative disease of the photoreceptors of the eye, inherited via an autosomal recessive gene. Usually the first symptom is night-blindness, especially noticeable when the dog is in unfamiliar surroundings, but eventually the dog goes totally blind. There is no cure.
SBCC runs Eye Testing Clinics for PRA annually at its Championship Show each spring, at Maidstone, Kent. Annual testing for PRA in adult BCs used for breeding is recommended.
For further details of the next show and Clinic please click here.
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DEAFNESS:
Figures from the Animal Health Trust indicate that 1 in 25 Border Collies tested suffers from congenital deafness. This still may not sound particularly important, but when you realise that the estimate for the incidence of deafness in the dog population as a whole is about 0.25 %, or 1 in 400 individuals, it begins to look a little more significant.
Even the most experienced Border Collie breeders sometimes do not recognise an affected puppy in the nest, especially one that is unilaterally deaf, and yet there are still people who are reluctant to hearing test, because “we haven’t got a problem”. However, the only way to know that for sure is to hearing test all breeding stock and progeny.
So how do we test for deafness? A skilled observer may sometimes identify bilaterally deaf dogs, as they often show very typical behaviour, such as the lack of response to loud noises, or remaining asleep when the other siblings are roused. But this subjective method of testing is open to misinterpretation as some normal animals may be unresponsive whilst others adapt quickly and stop reacting. A unilaterally deaf dog is very difficult to identify as it hears perfectly in the non-affected ear, and so usually behaves normally. It is almost impossible to confirm that a dog is unilaterally deaf without performing a more objective test, such as the Brainstem Auditory Evoked Response or BAER test.
The BAER is the electrical response of the brain to auditory stimuli. When sound enters the ear, the auditory pathway generates electrical impulses. These are picked up by recording electrodes, which are positioned on the head, and passed into a computer. A series of clicks are passed into the ear through a headphone, producing a repeatable sequence of peaks and troughs, which are displayed on a screen. The test is usually very quick and non-invasive, and gives an accurate and totally objective hearing assessment. Puppies are tested from 5 weeks of age, and adults can be tested too, although a light sedation may be required. With this kind of deafness, all the peaks in the BAER waveform are lost, so a straightforward yes-or-no assessment of hearing ability is possible. If the characteristic trace is acquired from both ears, the animal hears normally.
Now that the BAER test is available, no-one need ever find out that their much-beloved but somewhat wayward puppy behaves that way because he is in fact totally deaf, as it is no longer necessary to purchase a puppy whose hearing status is unknown. This is the aim of hearing testing – to ensure that breeders know the hearing status of the pups they are selling and to reduce (or in a perfect world, eliminate) the incidence of deafness in the Border Collie breed. Eventually it is hoped that a blood test will be available to identify carriers of the disorder, but until then, the only way to know with certainty the hearing status of each individual, and go some way towards reducing the percentage of affected dogs, is to evaluate every animal using the BAER test.
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