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| Our Thanks to the Border Collie Club of NSW for the information provided below |
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Click here for: Pedigrees of proven carriers For pet owners it should be emphasised that:
Prospective breeders of Border Collies should be aware of the need for very careful selection of breeding animals and all subsequent matings. HISTORY Early this century, F.E. Batten studied and described the condition known as Ceroid Lipofiscinosis or Batten’s Disease in children. Variations of this condition are now apparent in several species including dogs, cats, sheep and cattle. CL in Border Collies is of particular interest to medical researchers as it is nearly identical to that in humans. It is hoped studies carried out in Australia and overseas will not only benefit our breed, but also the unfortunate children stricken by this disease. In June 1980, a 17 month old bitch was referred to Melbourne University, Werribee, suffering from “fits” and “sight problems”, but no diagnosis of any inherited problem was mentioned to the owners. In December, 1980 a 19 month old male was also seen at Werribee and after observation for several days and enquiries made to the Eye and Ear Hospital, Melbourne, it was suggested that the dog was suffering from a disease seen in children known as CL for which there was no cure. The dog was therefore put down. The earlier case was reopened and compared with that of the second dog. Melbourne University were convinced both animals were suffering from the same condition. Several years later, in 1985/86, pups from three separate litters were diagnosed as having CL. Again there was a lapse of time when no cases were reported. A further 9 litters were affected late 1988 to early 1991. The number of affected cases has been very small, but there must be carriers in our current Border Collie population and extreme care is very important in breeding programs. A further case was discovered in NSW in 1996 with no known carriers appearing in four generations behind this dog. The most recent cases discovered were in 2002. One with full pedigree and one from a working dog with no traceable pedigree. VETERINARY ASPECTS OF CL Ceroid Lipofuscinosis is one of a group of diseases known as “Metabolic Storage Diseases”. It is: - A model for the disease in humans, which is known as Batten’s Disease. - Characterised by the accumulation of ceroid lipofuscin, a waxlike lipid waste product of cell metabolism. - Under normal circumstances many types of body enzymes remove cell waste matter but with CL one of these enzymes is missing. - NOT contagious. CLINICAL SIGNS Affected animals are normal at birth and remain so until approximately 18 months of age. However, from the embryonic stage there is a metabolic defect, the nature of which is not understood. The effect of the defect is to allow the waste product “ceroid lipofuscin” to accumulate in the cells of many tissues of the body. In the brain there is very little room for storage of waste products. By 18 months of age sufficient waste product has been accumulated to begin compressing and destroying the healthy brain tissue. At this stage the dog/bitch may begin to show some/all of the following signs: - Unreasonable apprehension of familiar surroundings and objects. - Lack of concentration and apparent loss of sight. - Abnormal gait - dogs are unsteady, tend to prop, goose-step and have difficulty with jumping, climbing and placing their feet. - Dementia, mania, hyperactivity and rage. No affected animals have been kept beyond 28 months of age, as the signs are too severe to allow dogs to continue. INHERITANCE OF CL Current information and research shows that CL has an autosomal recessive mode of inheritance. This means that: - Offspring must receive the CL gene from both sire and dam to develop the disease. - Both males and females are equally susceptible. - Individuals There are therefore three genetic possibilities: (a) a dog/bitch that is absolutely free of the disease; (b) a dog/bitch that does not show the disease but is a carrier; (c) a dog/bitch that develops symptoms of the disease with time.
ORIGIN OF CL IN BORDER COLLIES With the pedigrees of three separate show breeding lines and now one from the working lines, to work from, it is possible to trace the probable introduction of CL into Australia. It would seem most likely the original mutation occurred in or behind a working dog imported from the U.K. into New Zealand around 1950, with subsequent progeny coming to Australia. There have been two confirmed cases amongst the working dogs in N.Z. which would seem to support this. The following diagrams show the types of matings that are possible within the breed. Each dog has a pair of genes - one from each parent.
Two important points to be noted are:
It must be stressed that the occurrence of CL in Border Collies is not the fault of any one person or group. It was unknowingly introduced into this country and has probably lain dormant for many years before being officially recognised. It is a breed problem affecting all breeders throughout Australasia, currently not a widespread problem and hopefully one we can control. DIAGNOSIS Diagnosis of the disease is now possible by use of a brain biopsy that can be carried out at approximately 7 months of age and can be done in any State of Australia - in consultation with either the University of NSW or the University of Melbourne. Further research is needed however, before an animal can be diagnosed as a carrier. The aim of current work in NSW is to develop a DNA test which would be performed on blood or even a hair to determine if a dog is a carrier. This is looking promising at present. For this genetic fault there is no treatment possible at this stage. Any Border Collie owner who suspects they have a problem should contact their Veterinarian and/or Dr. Scott Melville (University of NSW) or Dr. Russell Mitten (University of Melbourne). If an animal you own produces a CL carrier, please do not desex the animal immediately. Please contact either Scott Melville or Alan Wilton as soon as possible, as we may be able to use these animals to help with our research. Contact persons - inform the breeder, and/or the Secretary of the relevant Border Collie Club in your State or: |
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Dr Scott Melville Click here for: More CL Information Click here for: Pedigrees of proven carriers |
