Experimental design used to estimate proportion of crows able to pass infectious RML scrapie prion (PrPRes) in feces (numbers of animals).

AMice intraperitoneally inoculated with gamma-irradiated crow fecal (CF) extract from crows gavaged with PrPRes (+) or control (−) mouse brain homogenate; additional control mice were inoculated with mouse-brain homogenate with (MB+) or without (MB−) PrPRes.BFive mice were randomly allocated to each crow and housed together in 1 cage postinoculation. Additional control mice were allocated randomly to MB treatment groups and 5 mice/treatment group were housed together in 1 cage postinoculation.