The effect of automated blood sampling on corticosterone levels, body weight and daily food intake in permanently catheterized male BALB/c mice.

BACKGROUND/AIM Automated blood sampling has the benefit of sampling without human intervention, thus minimizing the associated stress response. Since this technique has not been thoroughly investigated in mice, the present study was designed to evaluate this technology in mice. MATERIALS AND METHODS Male catheterized BALB/c mice were subjected to automated blood sampling, fecal sampling and daily recording of body weight and food intake for three days post-surgery. Corticosterone levels in blood and feces were investigated as biomarkers of stress. RESULTS Plasma corticosterone levels were elevated, and the circadian rhythm was disrupted as reflected in both plasma and feces. The body weight and daily food intake declined for the first two days post-surgery and increased at day three. DISCUSSION These results demonstrate that surgery and subsequent automated blood sampling induce a stress response for up to three days post-surgery, and it is concluded that further refinement of this technique is essential.