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The BVA / Kennel Club Eye Scheme
Developing a test for Hip and Elbow Dysplasia
Labradors at work: Conservation Canines
Completing your dog’s results
Fireworks night
The BVA / Kennel Club Eye Scheme
Over the past 40 years the British Veterinary Association (BVA) and Kennel Club (KC) have been working together to promote responsible dog breeding through health screening tests. Whilst many people are aware of the hip and elbow joint scoring schemes, perhaps fewer are aware of the scheme which also exists to identify dogs affected by inherited eye diseases.
The British Veterinary Assoication / Kennel Club (BVA/KC) eye scheme is not new; it has been in place for over 30 years and has evolved to cover eleven hereditary diseases found in fifty pedigree breeds. The scheme has proven to be important on two levels. Firstly, it is possible to identify those individuals affected by proven hereditary ‘schedule A’ diseases (listed below), allowing breeders to select animals free from disease. Secondly, it is possible to monitor the prevalence of ‘schedule B’ conditions that are suspected, but not proven, to be inherited. Information on schedule B conditions is used by scientists, but is not made public.
The Labrador is affected by five schedule A conditions:
- Total retinal dysplasia
- Multifocal retinal dysplasia
- Generalised progressive retinal atrophy
- Central progressive retinal atrophy
- Hereditary cataract
Total and multifocal retinal dysplasia are both conditions where the back of the eye (the retina) does not develop properly. In the severest form, total retinal dysplasia, the affected individual is blind from birth. In animals affected by generalised and central progressive retinal atrophy, the retina develops correctly, but later in life it may degenerate. Initially they may cause night-blindness which may eventually progress to complete loss of vision. Hereditary cataracts are marks on the lens inside the eye, which may or may not affect vision.
In accordance with the other BVA/KC health schemes, all dogs being tested for eye diseases must be presented with their official registration papers, and those aged over 12 weeks old must have a form of permanent identification (microchip or tattoo). There is no minimum age for testing and in many circumstances it is recommended to annually retest individuals. This is due to the varying age of onset for diseases, with some being present from birth, some having early onset, and others only becoming apparent when the animal is an adult. It is generally recommended that most dogs should first be tested after their first birthday and before they are bred.
The eye test is performed by a specially appointed veterinary ophthalmologist. A list of the panellists and details of their clinics can be found at: http://www.bva.co.uk/public/documents/EP_list_Jan_2011.pdf.
The test itself comprises a careful examination of the eye and surrounding tissues. It usually involves placing eye-drops into the eyes to temporarily dilate the pupil, allowing a better view of the back of the eye. The vet uses a series of specialist instruments and lenses, with most of the examination taking place in a darkened room. Most dogs tolerate the examination very well, although sometimes it is a challenge to keep the most exuberant patients still.
When the examination is over, a certificate is issued which records the animal’s identity and the absence or presence of signs compatible with schedule A and B conditions. There is also a section which allows any other ocular abnormalities to be recorded, such as in-growing eyelashes or scars from previous trauma. The BVA/KC has an online database which publishes an animal’s schedule A disease status, alongside information on hip and elbow scores.
The biggest limitation of the BVA/KC scheme is it only detects those individuals that are displaying signs of disease at the time of the examination. As previously mentioned, some conditions will only become evident in adulthood when an animal may already have been used for breeding. It also does not detect carriers of disease, who possess genes associated with disease, but do not display clinical evidence themselves.
The future of screening dogs for eye diseases is likely to involve genetic screening. This method enables the detection of carrier animals and those who will only display signs later in life, but relies on identifying the genes responsible for the diseases. Genes responsible for progressive retinal atrophy have already been identified, and it is likely that more tests will be developed in the future.
Want to check the eye test result of your Labradors parents? Why not visit http://www.the-kennel-club.org.uk/services/public/mateselect/test/Default.aspx to find out.
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Developing a test for Hip and Elbow Dysplasia
The Labrador Retriever Hip and Elbow Dysplasia study is a nationwide project which is aiming to develop a DNA-based test for genetic risk of hip and elbow dysplasia. Hip and elbow dysplasia are developmental disorders which result in malformations of their respective joints, which can result in pain and discomfort of affected dogs. These conditions have been found to be among the most prevalent affecting the health and welfare of Labrador Retrievers.
Recent progresses in genetic research mean that we can now analyse hundreds of thousands of variations in the DNA sequence from a single dog, for a relatively modest cost. By analysing the patterns of these DNA changes across a large population of dogs who have been screened for hip and/or elbow dysplasia, it should be possible to develop a genetic test for these diseases. The genetic test for these diseases is particularly advantageous over the normal X-ray based tests, as the genetic test will;
- improve welfare as it will not require dogs to undergo anaesthesia or be exposed to X-rays to test them
- allow breeders to test dogs soon after birth
- improve breeders' ability to select against these debilitating diseases
- result in much quicker progress towards the goal of eradicating hip and elbow dysplasia
The project was launched in 2010, when the UK Kennel Club sent out a questionnaire to owners of Labrador Retrievers aged 4 - 7 years (born between 2004 and 2007) with a Hip Score in the British Veterinary Association / Kennel Club database. On receipt of these completed questionnaires, owners agreeing to participate were sent a DNA-sampling kit (mouth swab) and instructions on how to take the sample. In return, participating owners will receive feedback on the progress of the project and invitations to attend related workshops. It is hoped that the preliminary results of the analysis should be available in the autumn of 2012.
The project is being run by the Animal Health Trust, and the Roslin Institute and Royal (Dick) School of Veterinary Studies at the University of Edinburgh, and the project is generously funded by the Biotechnology and Biological Sciences Research Council. For more information on the study please visit http://www.aht.org.uk/cms-display/labrador.html. To view previous Dogslife articles on hip and elbow dysplasia, click on the links below.
Hip dysplasia: http://www.dogslife.ac.uk/newsletter/view/5#hip
Elbow dysplasia: http://www.dogslife.ac.uk/newsletter/view/8#elbow
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Labradors at work: Conservation Canines
All over the world there are species of animals at risk of decline due to environmental factors such as the deterioration of their habitat or poaching. In order to manage and conserve wildlife appropriately, more information must be gathered on the health, abundance and distribution of the population of species under threat. Since many of these endangered animals live in remote, inaccessible or varying locations, and may be well camouflaged, nocturnal, aggressive, or have a tendency to flee, it can be difficult to monitor them. Traditional methods include trapping, radio-collaring, and setting up cameras, all of which can be intrusive. Since dogs have a heightened sense of smell and can cover large areas quickly, they can be trained to become effective and efficient aids in tracking endangered animals by locating their scat (excrement). A sample of scat can be analysed by scientists to find out important information about a population’s health and whereabouts, eliminating the need to use invasive methods.
The idea of using dogs to detect an animal’s scat was developed by Dr Samuel Wasser in 1997 with the help of Sgt Barbara Davenport, Master Canine Trainer with the Washington State Department of Corrections. From their work, Conservation Canines was set up. Since then, the Conservation Canines program (based at the Centre for Conservation Biology, University of Washington) has been working to gather information on a wide variety of animals; orcas, bears, giant armadillos and jaguars are just a few examples of species being monitored globally.
Scat detection dogs are helping to uncover important physiological and genetic information. For example, the DNA found in scat can tell us the sex and identity of the species which in turn allows an estimate of the size and distribution of the population in a given area. DNA from the food the animal has eaten can also be found in a scat, providing key information on the animal’s diet. Scat can also be examined for hormones which indicate stress and reproductive health, and the animal’s immune system and the amount of toxins they have been exposed to can also be identified. Over time, this portrays any environmental changes or influences the species has been susceptible to. As with all the data entries completed by Dogslife members, frequent analysis provides a complete health profile without the need for invasive testing.
Dogs between the age of 18 months and 3 years old can be enrolled on to the Conservation Canines program. However, they must have an excessive drive to play with their ball since this is the reward they receive for sample detection. The most popular dogs are working breeds e.g. Labradors, German Shepherds and Border Collies. Dogs are paired with a handler (who is accommodated on site with the dog), and the team work together every day. A typical day for a scat detection dog is an hour of exercise in the morning followed by practice training for the rest of the day. Dogs work 7 days per week unless they are on location, where the field work can be exhausting, in which case dogs usually work for 3 days and then have a day off. Dogs are trained not to chase after animals if they see them in the wild. A bell is fitted to the dog to warn animals in the vicinity of their presence.
Scat detection dogs usually work until they are about 8 or 9 years of age. After this time, some dogs may continue to work on matching samples indoors, rather than in the field, so they no longer have to do any work that is too physically strenuous. Others may be adopted by families, or by their handler who has formed a special bond with the dog and wishes to keep them.
Conservation Canines are contracted to work all over the world, providing comprehensive non-invasive research on endangered species. For more information, please visit http://conservationbiology.net/conservation-canines/
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Completing your dog’s results
Thank you to all the members who keep their dog’s record up to date. You may have noticed that we have made a few changes to the questionnaire recently. Firstly we have added a question on whether your dog has travelled abroad, and if so, a text box to for you to tell us when and where they have travelled. If you have registered your dog with a vet (and therefore answer ‘Yes’ to that question) this question will no longer appear the next time you complete a data entry. For dogs over one year of age, we have omitted the height question since no increase in height would be expected after this age as dogs are skeletally mature. We appreciate that to weigh your dog may require a trip to the vet or the local pet shop to use their scales. If you do not have your dog’s weight when it is time to enter your dog’s results, you can still complete the questionnaire without it. Your dog’s weight is an important part of your dog’s record so when you have it, you can add it to their profile directly by clicking on the link under their weight graph. We hope these changes will help to make completing information on your dog quicker and easier.
If it has been a while since you have told us about your dog’s health and lifestyle we would love to hear how they have been getting on. All the information you provide is invaluable to our research. To update your dog’s record, you can login at www.dogslife.ac.uk using your email address and password, and click on the red button entitled, ‘Enter your dog’s monthly results’. We look forward to finding out how your dog progresses and hope to hear more about them soon!
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Fireworks night
As fireworks night is nearly here, you may wish to click on the following link to read Dogslife’s previous article about keeping your dog safe on fireworks night: http://www.dogslife.ac.uk/newsletter/view/4#fire
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Don't forget to come back to Dogslife to update your dog's record www.dogslife.ac.uk
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