July 6, 2009

Rare sheep may aid medical diagnostics

U.S. scientists say rare sheep called hair sheep could be a key to improving medical diagnostic tests conducted in the developing world.

Hair sheep, the scientists said, do not have long, woolly coats that require shearing. But, more importantly, researchers at the Stanford University School of Medicine found not only are the sheep low-maintenance and parasite-resistant, they're also perfect blood donors for microbiology tests necessary to diagnose infectious disease in the developing world.

Identifying microbes from a patient's urine or sputum requires growing microbes in culture dishes filled with gelatinous agar and a small amount of blood to provide nutrients to the microbes.

In the developed world, microbiologists use sheep or horse blood. But in many parts of the developing world, horses are prohibitively expensive, and regular sheep are difficult to keep alive.

But when the researchers tested blood from hair sheep and ran a series of common diagnostic tests they found it worked for every single thing, Professor Ellen Jo Baron, who led the study, said.

Baron said her team also found hair sheep blood can be easily collected in donation bags, much like those used for human donors and does not need defibrination to remove fibrin, as does human blood.

The research that included Drs. Benjamin Pinsky, Niaz Banaei and Ellen Yeh is detailed in the online journal PLoS One.