Numbers of mice by treatment group that suffered early inoculation-related death, exhibited clinical symptoms of prion disease, and tested positive for scrapie prion (PrPRes) by ELISAA.

ANumbers in parentheses indicate sample size.BMice 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.CMice that died ≤3 d postinoculation, presumably from fecal uric acid toxicity. These mice were removed from the data set.DMice that achieved a minimum threshold score, based on multiple symptoms such as kyphosis, ataxia, stiff tail, lack of grooming, emaciation, and lethargy, demonstrating strong clinical evidence of prion disease.