Lavender Foal Syndrome test now available.

The Animal Health Diagnostic Center at Cornell University is now offering a genetic test for Lavender Foal Syndrome (LFS).

LFS is a fatal disease of newborn Arabian foals, particularly those of Egyptian Arabian breeding.

Signs shown by affected foals include seizures, nystagmus (involuntary movement of the eyeballs), limb rigidity, paddling movements, and opisthotonus (hyperextension of the head, neck, and spine).

The condition gets its name from the abnormal coat color with which most affected foals are born, variably described as silver sheen, lavender, pale chestnut or pale, dull pinkish grey.

Scientists at Cornell University and the Maxwell H Gluck Equine Research Center have found that Lavender Foal Syndrome is the result of a mutation in a gene called myosin Va (MYO5A). All affected foals tested in the study were homozygous for this mutation (i.e. both copies of the gene were defective).

Lead researcher was Samantha A. Brooks, PhD, assistant professor in the Department of Animal Science at Cornell University's College of Agriculture and Life Sciences.  “Our results suggest that the population frequency of carriers of this deletion is 10.3% in the Egyptian Arabian,” she reports.

“From a practical standpoint, this discovery and the development of a diagnostic test for the LFS allele provides a valuable new tool for breeders seeking to avoid the disease in their foal crop.”

Testing of breeding animals is recommended to identify carrier horses. The breeding program can then be arranged to avoid mating two carriers, and so prevent the birth of an affected foal.

The test can be run on hair roots pulled from the mane or tail, or whole blood samples.

Normally, the AHDC only accepts samples from accredited veterinarians. However, for this test, Arabian owners are encouraged to submit their own pre-paid samples directly to the laboratory.

The Lavender Foal Syndrome test is not restricted to horses within the USA. Shipment of EDTA whole blood samples from abroad requires a USDA permit. However, according to the laboratory no permit is required for sending hair samples.

(Permits may not be available for the import of blood specimens from some countries. Please contact the laboratory (Lisa Bowen-Laue; 607-253-3938) for the appropriate permit if you wish to submit EDTA whole blood for LFS testing from outside the USA.)

Each sample must be sent with a completed LFS assay submission form. Payment, ($47 for each horse tested) must accompany the samples unless they are submitted by a licensed veterinarian.

Information on the new test, including full instructions on how to submit samples, can be found on the LFS page of the Cornell University College of Veterinary Medicine website.