Fig. 6
Various rearing methods and behavioral changes in the AtT, GOFT, and TT. (a) Group rearing of 12 rats in an enriched environment (EE) prepared in a complex housing. (b) Rearing with gentle stroking (GS): rats gently stroked on the back with a cosmetic brush. (c) Attachment test (AtT). Rats reared with 5 different methods were subjected to AtT; ‘yes’ and ‘no’ denote succeeded and failed in the AtT, respectively. F1: offspring of EAH rat parents. (d, e) Grouped OFT (GOFT): four cage mates were released to the OF, and the mean distance between the rats was measured for 5 min (d). (e) GOFT with an unknown rat: mean distance between the cage mate and the unknown rat. (f) Duration spent in the live or dead zone in the triage test (TT). (g) The comparison of the duration spent in the live and dead zones by individual rats. (h) Number of contacts with the heads of comatose and euthanized rats in TT. (i) The comparison of the number of contacts with the heads of the comatose and euthanized rats by individual rats. n = 24, except for GS group (n = 16). (c) χ2 test and Fisher’s exact test; (d, e) a one-way ANOVA and Tukey’s multiple comparison test; (f, h) a two-way ANOVA and Sidak’s multiple comparison test; (g, i) paired two-tailed t-test. *, **, ***, **** indicate statistical significance at p < 0.05, 0.01, 0.001, and 0.0001, respectively.
