Gene for PSSM type 1 in European draught breeds

PSSM is a metabolic disease that results in the accumulation of glycogen and abnormal polysaccharide in muscle.

A genetic mutation of the glycogen synthase1 gene (GYS1) has been identified as the cause of some cases of PSSM in quarter horses and North American draft breeds. This form of the disease has been classified as type 1 PSSM.

A recent study has now also found the GSY-1 mutation in continental European draught breeds.

With the cooperation of the breed societies, Dr John Baird and colleagues sampled Ardenner, Belgian Draft, Breton horse, Comtois, Trait du Nord, Hispano-Breton, Netherlands Draught horse, and German cold bloods.

Overall 62% of continental European draft horses possessed the GYS-1 mutation. The mutation was present in all breeds sampled and in all six countries (Belgium, France, Spain, Germany, Sweden and the Netherlands.)

Of the breeds in which more than 15 animals were tested, the Belgian trekpard had the highest number of horses with at least one copy of the GSY1 gene (92.1%). Over a third of the Belgian trekpard tested were homozygous for the GSY1 allele - that is they carried two copies of the defective gene. The mutation was also present in over 50% of the animals tested from the Comtois (79.8%), Netherlands trekpard (73.9%), Rheinisch-Deutsches kaltblut (68%) and Breton (64.4%) breeds.

"What is striking from the present study" say the authors" is that a high percentage of horses derived from continental European draught breeds, in fact, often the majority of horses tested in each breed, were positive for the GYS-1 mutation."

However they stress that, as the research was not based on random samples, it cannot be relied on to give an accurate assessment of the prevalence of the GSY-1 mutation in continental European breeds.

For more details see: http://www.equinescienceupdate.com/articles/gpedb.html

Latest stem cell research results

Stem cell treatment reduces the rate of repeat injuries when used for treating superficial flexor tendon injuries in racehorses, according to research at the Royal Veterinary College.

Professor Roger Smith developed a technique for harvesting stem cells from the bone marrow, multiplying them in the laboratory and then implanting them back into damaged tendon.

So far, the procedure has been used in over 1500 horses throughout the world. Monitoring the healing process using ultrasound scans showed that the hypoechoic "core" lesion filled in quickly, although a reduced longitudinal striated pattern usually persisted.

A study of the clinical outcome in 113 treated racehorses, found that the re-injury rate was significantly lower in stem cell treated horses than in conventionally treated horses.

Histopathological examination of 17 tendons from post mortem samples obtained from horses that  had undergone stem cell implantation showed both good quality healing with minimal inflammatory cells, and crimped organised collagen fibres.

A further experimental study found that stem cell treated tendons had more normal mechanical  characteristics and their shape, appearance and composition were also improved. Tendon cross-sectional area, cellularity, crimp pattern and DNA content were all significantly better in the treated tendons than in the saline controls. Read more at www.equinescienceupdate.com

Obesity in English horses

Obesity is likely to be just as common in horses as it is in the human population.

A University of Nottingham study found that at least one in five leisure horses was overweight or obese. Owners were likely to underestimate body condition score.

Veterinary student Helen Stephenson assessed the prevalence of obesity among horses whose owners were registered with an equine veterinary practice.

Questionnaires were sent to five hundred horse owners, and 160 were returned. None of the horses was kept for breeding, livery, riding stables, or competition, so all were classed as being used for leisure only.

One in five owners indicated that their horses were either overweight or obese.

The owners were asked about their perceptions of their horses’ body condition, and asked to score this from zero to five, with a score of more than three indicating overweight.

The researchers then assessed the body condition of 15 randomly selected horses to see if the owners had under or overestimated the horse’s weight.

They assigned an average score that was significantly higher for these horses; eight of the owners had scored their horse at least one grade lower than the researcher had, indicating that the owners had underestimated their horses’ weight.

Based on the researchers’ findings, the authors estimate that the true prevalence of overweight/obesity was likely to be 54% rather than the 20% indicated by the questionnaire responses.

Read more at www.equinescienceupdate.com/obeng.html

Feral horse survival under changing environmental conditions

Australia´s recent heavy rain presents an opportunity to examine how feral horses are affected by the weather.
 
Magdalena Zabek has been working with the Australian Brumby Research Unit (ABRU), keeping a photographic record of their work. Now she is looking to complete a study of her own into the effect of a period of plentiful rainfall on the feral horses of central Australia (“brumbies”) following nine years of severe drought.
  
Currently the brumby population is estimated to grow at around 20% annually. It seems likely that the foaling rate in 2011 will be higher, due to the more favourable conditions during the 2010 breeding season.
 
In the ABRU December 2010 newsletter, she writes: "Information from this study will provide valuable information about fluctuations in numbers of feral horses due to the changes in availability of food and water, which is crucial knowledge when implementing population control methods. The study will also contribute to the development of better welfare outcomes for feral horses."
 
"The sudden increase in numbers will have an enormous impact on the feral population when the favourable climatic conditions change because the fragile semi-arid ecosystem is not able to meet the food and water requirements of feral animals during periods of less favourable conditions. When resources become scarce due to drought, the feral horses are forced to travel ever increasing distances to obtain adequate food and water, and, as a result, may die."
 
The findings of the study should help direct strategies used to manage feral horses, and hopefully reduce suffering and death during periods of drought.

Read more in the ABRU December 2010 newsletter.
http://www.wildhorseresearch.com/Documents/Newsletters/December%202010.pdf
 
For more information about Magdalena´s art work see:
http://www.magdalenas-art-work.22web.net