A new congenic strain of obese mice, C57BK/KsJ-ob, has been developed for comparison
with the C57BL/6J-ob congenic strain. While obese mice of both strains are characterized by
obesity, hyperphagia, and hyperglycemia, the C57BL/Ks obese mice have severe diabetes,
marked hyperglycemia, temporarily elevated plasma insulin concentrations, and typical
degenerative changes in the islets of Langerhans. In contrast, the C57BL/6J obese mice
have mild hyperglycemia and marked hyperinsulinemia coupled with hypertrophy and …

Expression of the obese hyperglycaemic (bo/ob) syndrome in mice is modified by the
background genome. The Aston colony carries the ob gene on a mixed background which
produces a unique combination of different features shown by ob/ob mice on other
backgrounds. The maximum body weight of Aston ob/ob mice exceeded that of other
colonies, possibly reflecting a trait for higher growth rate in the background genome. The
hyperphagia, marked hyperinsulinaemia and moderate hyperglycaemia observed during …