Decreased recovery times were observed after repeated handling and anesthesia sessions.

A cohort of 8 adult rats was anesthetized once a week, for 12 weeks, with 2.5% isoflurane (4 L/min O2) for 1 hour in an anesthesia machine. The figure plots the average time it took for the rats to emerge from anesthesia (large filled green circles), every week. Each average from weeks 2–12 was compared to that obtained in week 1, using a repeated measure ANOVA. The “*” corresponds to a significant difference in the average values, p <0.05. The “**” denotes p<0.01. The raw data is plotted just to the left of each average as small filled black squares.