Complex sentence: In this model, a mouse if fed a high fat diet, typically for 8 to 12 weeks and, as a result, become obese, mildly to moderately hyperglycemic, and develop impaired glucose tolerance.
Split into simpler sentences: In this model, a mouse is fed a high fat diet, typically for 8 to 12 weeks. As a result it become obese, mildly to moderately hyperglycemic, and develop impaired glucose tolerance.