Fig. 1.

Prion-infected Ub^G76V-GFP reporter mice display sudden decline in burrowing behaviour from 15 wpi. Ub^G76V-GFP reporter mice were inoculated with 30 μl of 1 % RML prion-infected brain homogenate or 1 % uninfected brain homogenate at 8–10 weeks of age. Burrowing behaviour was assessed by measuring the percentage of food pellets displaced from a plastic burrow placed in single-housed cages overnight. Significant impairment of burrowing behaviour was observed from 15 wpi in prion-infected animals (blue line) versus uninfected controls (grey line). Data are percentage mean ± SEM (***p < 0.001; mixed model ANOVA with Bonferroni post hoc tests; n = 9 per group)