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| Model category | Advantages | Disadvantages |
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| (I) Spontaneous diabetic animals | Development of type 2 diabetes is of spontaneous origin involving genetic factors, and the features resemble human type 2 diabetes | Highly inbred, homogenous and mostly monogenic. Inheritance and development is genetically determined, unlike heterogeneity of humans |
| Most inbred animal models are homogeneous and environmentally controlled, that allows easy genetic dissection | Limited availability and expensive. Mortality due to ketosis is high in animals with brittle pancreas (db/db, ZDF rat P. obesus, etc.), and it requires insulin in later stage for survival |
| Variability of results is minimum and require small sample size | Require sophisticated maintenance |
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| (II) Diet/nutrition induced diabetics | Develop diabetes with obesity due to over nutrition like diabesity syndrome of human | Mostly require long dietary treatment |
| Toxicity of chemicals on other vital organs can be avoided | No frank hyperglycaemia develops upon dietary treatment in normal animals and hence unsuitable for screening antidiabetic agents on circulating glucose parameters |
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| (III) Chemical induced diabetic animals | Selective loss of pancreatic beta cells (alloxan/STZ) leaving alpha and delta cells intact | Hyperglycaemia develops by cytotoxic action on the beta cells, leads to insulin deficiency rather than insulin resistance |
| Residual insulin secretion help animals to live long without insulin treatment | Diabetes induced by chemicals is less stable and is reversible due to spontaneous regeneration of beta cells. Thus, care is required to assess beta cell function in long-term experiments |
| Ketosis and mortality is relatively less | Chemically induced toxicity on other organs along with its cytotoxic action on beta cells |
| Comparatively cheaper, easier to develop and maintain | Variability of results on development of hyperglycaemia is high |
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| (IV) Surgical diabetic animals | Avoids cytotoxic effects of chemical diabetogenes on other organes | Involvement of cumbersome technical and post operative procedures |
| Resembles human type 2 diabetes due to reduced islet beta cell mass | Occurrence of some digestive problems, due to excision of exocrine portion leads to the deficiency of amylase |
| Dissection of alpha cells (secreting glucagon) along with beta cells leads to the counter regulatory response to hypoglycaemia |
| Mortality is comparatively higher |
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| (V) Transgenic/knock out diabetic animals | In vivo effect of single gene or mutation on diabetes can be investigated | Highly sophisticated and costly for production and maintenance |
| Dissection of complex genetics of type 2 diabetes is easier | Expensive for regular screening experiments |
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