Repeated administration of tribromoethanol in C57BL/6NHsd mice.

We evaluated the effect of repeated intraperitoneal administration of tribromoethanol on various parameters in C57BL/6NHsd mice. Mice (n = 68) were randomly assigned to 1 of 7 groups to receive tribromoethanol (500 mg/kg IP) on day 0 or days 0 and 8; vehicle (tert-amyl alcohol in sterile water) only on day 0 or days 0 and 8; sterile water injection on day 0 or days 0 and 8; or no treatment. A single dose of tribromoethanol failed to produce loss of pedal reflex and had no effect on median food and water consumption but altered median body weight on days 1 through 4 when compared with that in mice that received vehicle only or no treatment. Median body weight did not differ between mice that received a single dose of tribromoethanol and those that received an injection of water. Among mice given 2 doses of tribromoethanol, induction time, anesthetic duration, and recovery time varied widely. Repeated administration of tribromoethanol had no effect on median food and water consumption or body weight compared with those in controls. Median liver weight was significantly greater in mice that received 2 doses compared with a single dose of tribromoethanol. Median liver weight did not differ between untreated mice and those that received tribromoethanol. No significant organ or tissue pathology was observed in any study animal. Although tribromoethanol did not produce morbidity, mortality, or pathologic changes in treated animals, we urge caution in use of tribromoethanol in C57BL/6NHsd mice due to its variable anesthetic effectiveness.

Effects of buprenorphine, meloxicam, and flunixin meglumine as postoperative analgesia in mice.

C57BL/6NCrl male mice (n = 60; age, 6 to 7 wk) underwent partial hepatectomy or no surgery and were given 1 of 3 analgesics pre- and postoperatively. Food and water consumption, body weight, running wheel activity, locomotor activity, and serum corticosterone concentrations were measured before and after surgery. Mice that were surgically manipulated weighed significantly less on days 1 through 3 after surgery than did mice not manipulated surgically. On the day of surgery, the surgery groups consumed significantly less feed (-1.5±0.35 g) than did nonsurgery groups. There were no differences in water consumption on any day between surgery and nonsurgery groups or among the 3 analgesic groups. For running wheel activity, significant decreases in the surgery groups were seen at day 1 after surgery compared with baseline. Surgery groups that received buprenorphine and meloxicam returned to baseline activity levels on day 2 after surgery. Open-field testing revealed no significant differences in locomotor activity in any groups; however, posttreatment locomotor activity in the buprenorphine nonsurgery group was increased compared with baseline, and posttreatment locomotor activity in the flunixin meglumine surgery group was decreased compared with baseline. Serum corticosterone concentrations were within normal limits regardless of treatment in all groups. Comparison of the overall results indicated that meloxicam and buprenorphine, at the dose given, appear to be suitable postoperative analgesics for partial hepatectomy in mice. Flunixin meglumine at the given dosage (2.5 mg/kg) may not provide adequate analgesia for partial hepatectomy.