Goats and scrapie

Press, 14 August 1978, Page 16

Goats and scrapie

Sir, — Scientific experiments have demonstrated that goats can contract scrapie if their brains are injected with the brain material from scrapieinfected sheep and experimental mice. However, field experiments have so far shown no indication that goats can contract the disease under natural conditions, or that they are carriers of the disease. Therefore, Oliver Riddell’s

statement that “goats are most susceptible to scrapie” is a gross misrepresentation of the facts.—Yours, etc., IRENE RAMSAY. Balcairn.

July 31, 1978. [Professor A. N. Bruere, professor of veterinary niedicine/and clinical pharmacology, department of veterinary clinical sciences, Massey University, comments: “There is nothing essentially incorrect in Mr Riddell’s reporting. ‘Scrapie in Sheep and Goats,’ chapter 10, by A. G. Dickinson, publishers North Holland Publishing Company, 1976, editor, R. H. Kimberlin, gives the following points: The transmission of SSPPI derived scrapie to all of a group of crossbred goats at Compton by intra-cerebral injection (Patterson, 1957) was followed by its passage from goat to goats again with 100 per cent incidence and also back to Cheviot sheep. However, it would be unwarranted to make the sweeping extrapolation that all goats are 100 per cent susceptible to scrapie without specifying the genotypes, ages and routes of injection. It has become progressively clear that scrapie is a naturally occurring disease of goats (Chelle, 1942; MacKay and Smith, 1961; Hourrigan et al., 1969 and Harcourt and Anderson, 1974) and though the majority of the reported cases were in direct contact with affected sheep, this was not so in all cases. The author then goes on to describe how goats have been infected by a number of routes and that the classical signs developed are those called drowsy and scratchy, both forms of which are fatal as in sheep.”]