Sunday 29 January 2012

Genetic Diseases; why some people persist in breeding animals with them.

"Genetic Diseases in dogs and cats; What can we really do about them?"  (Robson, Mark. Vetscript, June 2009, page 6. Wellington, New Zealand)

What relevance does a paper on dogs and cats have to the issue of HWSS in ponies?  
Whatever the species, the principles of breeding sound, disease free animals is the same.  One of the comments Robson makes is that "one thing we have learned from dealing with breeders for many years is that logic does not often come into decision making".
Robson believes breeders are driven by the three 'Es': ego, emotion and economics. He goes onto express the opinion that for many breeders, the prestige of winning will overcome any long-term concerns genetic problems may cause in their dog's health.  Ego takes precedence over common sense.  Strong words?  Yes, but think about it.

Years spent breeding a line of animals with a particular appearance (type) which then turns up with a genetic defect is emotionally painful as well as a blow to the ego.  "Emotion may cloud a breeder's judgement and he or she may breed from favourites even when there is mounting evidence of ill-health in the line." (Robson).
The thought that years of hard work and breeding has resulted in the appearance of a genetic defect is very difficult for anyone to accept.  Denial is going to happen, it is a normal human response and is in fact the manner by which an individual's mental health is maintained until such time as they can cope appropriately with the challenge placed before them.  Also consider the scenario where all the animals on a property are afflicted. The defect is seen as 'normal' for the people who deal with the animals on an everyday basis and they actually cannot see that there is a problem, until it is pointed out by an uninvolved third party.

People who know that there is a problem within their breed (for example in specific dogs breeds  such as British Bulldogs or HYPP positive  horses) but who choose to continue to breed affected and afflicted animals are not 'in denial' from a mental health perspective.   Choosing to  continue to breed from these lines  is  considered to be more likely to be made on economic grounds.  Robson then goes onto say "where large numbers of animals are bred, concerns about individual animals and any genetic defects are lost in the herd mentality where the dollars are the primary endpoint" and is referring in this case to 'puppy mills'.  The equivalent to 'puppy mills' are found in horse breeding worldwide.
It is not all doom and gloom though.  Many breed societies do now have genetic screening tests for known genetic problems. To reduce the incidence in the population they require the results to be included on registration papers.   With some breeds and species a single copy of  a mutated gene is considered to be an asset, but active doubling up of the gene is strenuously avoided (for example the double muscling gene in breeds of beef cattle and sheep).   In most cases involving  horses  (as opposed to commercial food animals) the work to find out what the mutation actually is, has been both led and driven by the people most affected - the breeders who have had the misfortune to inadvertently breed affected ponies; this is certainly the case with the HWSS research.

Some countries now consider that breeding animals with a known genetic defect to be an Animal Welfare Issue, dictating that to do so is an offence under that country's legislation.  Now that the genetic link has been proven for HWSS, breeders within such jurisdictions will need to be assured of the HWSS status of any ponies which they may wish to sell or purchase in the future; to not do so could make  them  vulnerable to possible litigation. 

The next step in the HWSS journey is to find the specific mutation and develop a commercial screening test for it.  Once the screening test is perfected this will also be able to be used  for other horse/pony breeds.  The research group now has notifications from several individuals with concerns that HWSS also occurs in their own breeds.

Unless a problem is of high economic significance or of national or international importance, researchers only go 'looking' when 'someone' tells them that there is a problem which needs investigation; and of course also supplies the funding to pay for the research.


If everyone who reads this blog (and there are LOTS of you) were to donate $10, that would make a sizeable dent in the money needed to get the second stage of the research under way.   The last update from the Centre for Equine Health who are responsible for administering the donated funds for the HWSS research project was that the amount still required to start the second phase was $3500.00.

You can help the researchers at the Bannasch Laboratory help us, the breeders to 'get it right' with HWSS.  Put aside Ego, Emotion and Economics and make a small donation to UC Davis donation page