This has led some scientists to think a ewe can pass the disease to her lambs, but that has not been proven. Haskell says BSE and other spongiform encephalopathies are caused by virus-like protein particles called prions. Veteri-narians diagnose the disease through tissue evaluation in a laboratory. BSE in cattle and scrapie in sheep affect animals more than two years old, according to Haskell. Staggering, falling, partial paralysis, head and neck tremors, lack of coordination, emaciation and weakness are symptoms that affected animals may display.
Intense itch is common in sheep and goats.
No evidence exists that BSE transmission in cattle occurs other than through feed, says Haskell. It is very important not to feed cattle any protein that comes from a ruminant, such as meat and bone meal. Prevention of spongiform encephalopathies involves testing and destroying sheep and elk. Prevention measures in cattle include not feeding ruminant protein sources, as well as testing animals with symptoms of the disease.