Manganese linked to scrapie in cows, sheep

BATH, England, July 3 (UPI) -- British animal scientists have discovered manganese levels increase in scrapie-infected sheep just before clinical symptoms develop.

Scrapie is a fatal encephalopathic disease of sheep characterized by intense itching, excessive thirst, weakness and a general progressive degeneration of the animal's central nervous system.

The University of Bath-led study also found scrapie-resistant sheep produce elevated levels of the metal when challenged with the disease.

The researchers said their findings raise the possibility of using manganese levels in the blood as a potential diagnostic marker for prion infection. At present, only post-mortem examination of brain tissue gives a certain diagnosis.

Scrapie -- Bovine Spongiform Encephalopathy -- and Creutzfeldt-Jakob Disease are similar neurodegenerative diseases that affect the brain and nervous system of sheep, cows and humans, respectively.

The research builds on the 2002 discovery that mice infected with scrapie also exhibit higher levels of manganese. But the new study marks the first time tissue from farm animals infected with prion diseases have been studied in this way, said Professor David Brown, who led the study with colleagues from the universities of Hull and Edinburgh.

The research is published in the Journal of Animal Science.