Urine DNA profiling

Scientists will soon be able to use DNA profiling techniques to confirm the identity of racehorses that have tested positive to drugs.

Such a test would dispel any doubt about sample substitution and confirm that a sample did in fact come from a particular horse, helping to either confirm the identity of horses returning positive drug samples, or exonerating horse and trainer.

The report “DNA Profiling of Horse Urine Samples to Confirm Donor Identity” resulted from studies carried out by Paula Hawthorne and colleagues at the University of Queensland, and was funded by the Australian Government's Rural Industries Research and Development Corporation (RIRDC). The research team tested various techniques for DNA profiling on seven urine samples and compared the results with those from hair samples taken from the same horses.

They found that storage time and temperature had a significant effect on the success of the DNA profiling. Urine could be stored at 4°C for no more than two days (or frozen at -20°C or -80°C) before processing. Samples stored at 4°C for a week or more yielded no profiles.

The most successful technique, a commercially available test, allowed them to identify all twelve microsatellites, in four urine samples - all from male animals. As only seven samples were examined overall, it was not possible to tell whether that was a coincidence, or whether it really is more difficult to extract DNA from mare’s urine.

All DNA profiles from the urine samples matched those from the hair taken from the same horses.

There is still more work to do - for example, the researchers point out that drugs in the urine may interfere with DNA profiling. So once the best method of DNA profiling has been established, further tests will be required to assess whether the results are affected by drugs likely to be found in the urine.

However, the authors of the report suggest that once the optimum method has been finalised it should not take long to integrate it into existing procedures of racing drug-testing laboratories.

The full report is available for purchase or free download. See:
https://rirdc.infoservices.com.au/items/09-076

Risk of Atypical Myopathy cases this spring.

“There seems to be an increased risk of cases of Atypical Myopathy during the spring, when the disease has occurred during the previous fall” warns Dr Domonique Votion, of the University of Liege.

In the last few months of 2009, Western Europe experienced the largest ever series of cases of the disease, according to the Atypical Myopathy Alert Group (AMAG).

No less than 371 cases were notified to the AMAG. Of those horses, 265 died, giving a survival rate of just 22%. Most cases were reported in France (124) Germany (92), and Belgium (64).
Thirty-five cases were identified in the UK.

Horses with Atypical Myopathy suffer from severe, generalised weakness. They are often unable to get to their feet, or only do so with difficulty. If they are still able to walk, they do so with a stiff gait - especially of the hindquarters. Muscle tremors and generalised or patchy sweating may be seen.

Affected animals have elevated heart rates. They often have increased respiratory rates, with difficulty on expiration. The rectal temperature is usually below normal. Dark brown colouration of the urine is characteristic.

Despite the severity of the signs, horses often still seem keen to eat and will try to grasp hay that is held close to their mouth.

Often the first sign of disease is stiffness, especially of the hindquarters. However, it is not unusual for severely affected cases to be found dead on the pasture with no previous sign of illness.

For more details about the Atypical Myopathy and the Atypical Myopathy Alert Group see:

http://www.myopathieatypique.be

Disease surveillance report

The latest equine disease surveillance report published jointly by the UK Government’s Department for environment food and rural affairs (Defra), Animal Health Trust (AHT) and the British Equine Veterinary Association (BEVA), is now available. The report covering the period October - December 2009 has been uploaded recently to the Animal Health Trust website.

The Defra/AHT/BEVA equine quarterly disease surveillance report collates equine disease data arising from multiple diagnostic laboratories and veterinary practices throughout the United Kingdom. The current edition includes data from 30 laboratories and offers a unique insight into equine disease occurrence in the UK.

A form is available on the AHT website for registration to receive reports free of charge, via e-mail, on a quarterly basis.

See:

http://www.aht.org.uk/equine_disease.html

EMS research: help needed

Do you have a horse or pony with Equine Metabolic Syndrome? If so, scientists at the University of Minnesota's Equine Genetics and Genomics Laboratory would like to hear from you.

EMS is characterized by three main features: obesity or regional accumulation of fat (particularly in the crest or over the rump), insulin resistance and laminitis.

Some horses, often considered to be "easy keepers" by their owners, are more at risk of EMS than others. It is likely that the genetic make-up of the horse affects its susceptibility to the condition.

The aim of the study is to better understand the role in EMS of factors such as breed, gender, age, environment (diet and exercise) and genetics. To achieve this, the researchers need to collect data from as many horses with EMS as possible. So, they are keen to encourage horse owners and their veterinarians to get involved.

If you are interested in taking part in the Equine Metabolic Syndrome research project, the first step is to complete a short online survey. Within about one month, if your horse is considered suitable for the project, you will be asked to complete a second survey. This will ask for further information about the horse and about another horse, unaffected by EMS, that lives on the same property. This horse will serve as a "control". Ideally the control horse should be of similar breed and age, have no history of laminitis, not be overweight and show no signs of Cushing's syndrome (delayed shedding, increased drinking/urination).

The third step is to submit a blood sample to the laboratory, for biochemical analysis and DNA evaluation.

To identify the underlying genetic susceptibility to EMS, the scientists will compare genetic markers between horses with and without EMS. The genetic differences that are highly correlated to having EMS can be used as genetic markers for the disease.

The long-term goal is to use these EMS genetic markers to detect horses susceptible to EMS and laminitis before they have clinical signs. It may then be possible to change the management of susceptible animals to reduce the risk of them developing disease.


For more details about the study

http://www.cvm.umn.edu/equinegenetics/ems/research/index.htm

Rapid ringworm diagnosis

Scientists in South Korea have described a rapid method for diagnosing ringworm (dermatophytosis.)

Fungal culture is the “gold standard” method for identifying the species of dermatophyte involved, based on the colony characteristics and microscopic appearance. It is accurate but time consuming. Samples may have to be cultured for up to three weeks before the organism can be identified.

It’s not necessary to know the species before starting treatment. Indeed, to prevent the spread of infection, treatment is usually started pending the results of laboratory investigations.

However, there are occasions when it may be useful to know the identity of the dermatophyte involved, as it may help to identify the source of the outbreak. For example Trichophyton mentagrophytes can be found in soil and be carried by rodents.

Researchers at the Colleges of Veterinary Medicine at Seoul National University and Konkuk University compared a rapid molecular PCR assay with conventional fungal culture for diagnosing ringworm.

They found that the PCR analysis of the fungal DNA was superior to traditional fungal culture for diagnosing dermatophyte infection, “ in terms of sensitivity, specificity and particularly rapidity.”

Read more at www.equinescienceupdate.co.uk/rmmdd.htm