Actually I am trying to induce diabetes in rats but the result is not satisfactory. Because I am getting no results. the FBGL does not exceed beyond 126mg/dl. Now I am trying the same thing in mice but getting no results. The strain of the mice may be swis albino mice. But I could not understand how can I proceed further.
If this has ocuured in both rats and mice, then I suggest you check the drug you are using to induce diabetes; if it hasn't been well preserved it may no longer be potent. Secondly please ensure you are injecting correctly (intraperitoneally) and thirdly ensure that the drug (STZ or alloxan) is weighed appropraitely with a precision balance (small variations in dose may hamper induction of diabetes). I do not think there is anything wrong with the strain of animals you are using.
Can you please give details of your methodology, so I can have an idea what you did.
You could rodent strains that are genetically predisposed to develop diabetes e.g. db/db or ob/ob mice or Zucker or ZDF rats. But I agree with the others that in order to give advice we need to know more about your methodology