Comparative study of diabetes induction in rabbits and rats using streptozotocin: A pilot study

The study was aimed to induce diabetes mellitus in both Wistar albino rats and New Zealand white rabbits using Streptozotocin (STZ) to assess their suitability as models for diabetes research. Eight male rats weighing 190-240 g and eight male rabbits weighing 1.5-2 kg were administered STZ intraperitoneally at varying doses: 40 mg/kg body wt., 42 mg/kg body wt., 45 mg/ kg body wt., and 50 mg/kg body wt. in rats, and 45 mg/kg body wt., 50 mg/kg body wt., 55 mg/kg body wt., and 60 mg/kg body wt. in rabbits. Blood glucose levels were measured 72 hr post-administration to confirm the induction of hyperglycemia. The animals with blood glucose levels exceeding 250 mg/dL were classified as diabetic. Body weights were recorded on days 3, 7, 14, and 21 to monitor changes associated with diabetes. Rats receiving 45 mg/kg bodt wt. and 50 mg/kg body wt. STZ succumbed within 14 and 7 days, respectively (pancreas were collected for histopathology), while those administered 42 mg/ kg body wt. maintained blood glucose levels above 270 mg/dL for the entire 21-day study period. In contrast, rats given 40 mg/ kg body wt. did not sustain elevated blood glucose levels beyond 14 days. A marked reduction in body weight was observed in diabetic rats after day 3. However, none of the rabbits developed hyperglycemia at the administered doses, and there was no significant variation in body weight observed. All animals were euthanized on day 21, and pancreatic tissues were collected for histopathological analysis. The findings suggest that STZ at 42 mg/kg body wt. can reliably induce diabetes in rats, whereas the same is not achievable in rabbits at the doses tested. Therefore, rats serve as a suitable model for diabetes studies, while rabbits do not appear to be viable for this purpose using STZ.