Assessment of abdominal fat deposition in female cynomolgus monkeys

Computed tomography (CT) was used to assess abdominal fat distribution in adult, female cynomolgus macaques (Macaca fascicularis). The technique used was similar to that applied in human beings and allowed intra-abdominal, subcutaneous and total abdominal fat to be quantitated in 1 cm thick sections. Correlations between single scans and the average of scans at several levels ranged from r = 0.96 to r = 1.00, indicating that a single scan is representative of abdominal fat distribution. Significant positive correlations were found between body mass index (BMI) and intra-abdominal fat (r = 0.89), subcutaneous fat (r = 0.91) and total abdominal fat (r = 0.90). As BMI increased, fat was preferentially deposited subcutaneously versus intra-abdominally. A unique fat depot, not previously described, was identified dorso-laterally between the internal abdominal oblique and the transversalis muscle. This fat depot was also positively correlated with BMI (r = 0.79). These results indicate that CT can be used in cynomolgus monkeys to quantitate regional fat deposits and that these monkeys resemble human beings in their abdominal fat patterning.