Figure 6.

Strain- and age-associated changes in acute behavioral responses. (A) Variability between strains in the percentage of responders after tail biopsy is shown. Fewer BALB/c mice responded to the stimulus of biopsy, compared with other strains, at both 10- and 60-min observation periods after biopsy. Different letters above the columns indicate that those values are significant at P < 0.05 for either the 10-min (a, b) or 60-min (c, d) time point (n = 24 for each strain). (B) Cohort 2 mice show a significant reduction (marked with different letters [c, d]); P < 0.05) in behavioral responders over time compared with older cohort 3 animals (n = 72 animals for each cohort).