| TSE | Age of onset (yr) | Disease variants | Mode of transmission | Genetic predisposition | Clinical signs | Cross-species infectivity |
| Scrapie | 2–4 [33] | Classical atypical/Nor98 | Amniotic fluid and placenta [34] | Susceptibility 136V, 154R, 171Q [15] Reduced susceptibility 136A, 154R, 171R [16] | Weight loss Ataxia Abnormal behavior Sensory changes Incoordination Head tremors Recumbency [35] | Cattle, goat, mouse, hamster, rat, bank vole, deer, and elk [36–38] |
| BSE | 4-5 [39] | Classical H-type L-type | Contaminated feed [39] | Susceptibility [40, 41] 23 bp PRNP promoter insertion/deletion 12 bp PRNP intron insertion/deletion E211K | Weight loss Ataxia Abnormal behavior Sensory changes Incoordination Bradycardia Reduced rumination Decreased milk yield [42] | Bison, sheep, goat, deer, pig, mink, marmoset, cat, mouse, human, nonhuman primates [43] |
| CWD | 2–4 [24] | Possible varied conformer population [44, 45] | Animal contact and environmental contamination [20] | Susceptibility [20] Elk-132MM Mule Deer-132SS–225SS Cervid rigid Loop-S170N [46] -N174T [47] Reduced susceptibility [48] White tail Deer-Q95H-G96S | Weight loss Abnormal behavior Listlessness Incoordination Polydipsia Polyuria Hypersalivation Lowering of the head and ears Anorexia [21] | Moose, cattle, sheep, goat, mouse, hamster, ferret, mink, and squirrel monkey [20] |
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