Mink prions

It has been demonstrated that soil may serve as an environment reservoir for prions since hamster-derived PrPSc can adhere to soil minerals [34], Therefore, it is reasonable to argue that soil may be a source of CWD infection. Notably, oral transmissibity of infectious hamster-adapted mink prions (strains hyper and drowsy) is enhanced when bound to soil particles [41], Though cervids do not deliberately ingest soil, they do supplement their mineral intake by licking in regions of high clay content. 

Other animal prion diseases. Outbreaks of transmissible mink encephalopathy and chronic wasting disease in captive populations of mink, mule deer and elk in certain regions of the U.S.A. have also been attributed to prion-infected foodstuffs, although the origin of prion infection is unclear [8], Epidemiological studies suggest lateral transmission as the most plausible explanation for the spread of chronic wasting disease in captive populations... 

The transmission barrier of TME prions in mice was abrogated by transgenic expression of mink PrP on a knockout Prnp010 background [107]. 

Bessen RA, Marsh RF (1992) Biochemical and physical properties of the prion protein from two strains of the transmissible mink encephalopathy agent. J Virol 66 2096—2101... 

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