Infection via the gastrointestinal tract is likely to be a natural route of scrapie infection in
sheep. This paper describes the pathogenesis of the 139A strain of scrapie introduced
intragastrically (ig) into CW mice. There was an almost immediate uptake of infectivity and
onset of replication in Peyer's patches which preceded replication in spleen. Splenectomy
had no effect on incubation period suggesting that, in contrast to the intraperitoneal route,
the spleen plays little or no role in the pathogenesis of 139A scrapie administered …