Wednesday, 25 February 2015

Now we have the HWSD test this becomes very relevant. An edited version of an December 2011 post.

As people are getting their ponies tested for HWSD some of them are getting shocks at the results they are receiving. Feelings of  devastation and guilt, that maybe they have innocently helped to spread the problem further through the population, are not uncommon.

"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 HWSD 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.

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.

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).

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 horse and pony breeds do now have genetic screening tests available for known genetic problems. To reduce the incidence in the population they require the results to be recorded 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 these mutations actually are, 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 HWSD 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 HWSD, breeders within such jurisdictions will need to be assured of the HWSD 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.

A very important take home message is that any N/HWSD pony of breeding quality and selected HWSD/HWSD breeding quality ponies MUST NOT BE EXCLUDED FROM BREEDING.  If these ponies are excluded from the breeding population some of the best performance lines will become endangered.