Cholesterol and dominance rank in the Cayo Santiago macaques

The relationship between serum total cholesterol (STC) and social dominance rank was investigated in adult (greater than or equal to 5 year old) males of a single, naturally-formed free-ranging troop of rhesus monkeys (Macaca mulatta) on Cayo Santiago, Puerto Rico. Dominance rank, age and body weight were not correlated with STC, nor was rank correlated with age or body weight. The mean (+/- 1 SD) STC was 154.0 +/- 27.0 mg/dl. Seven of the 34 males sampled had STC levels (189.1 +/- 4.3 mg/dl) greater than 1 SD above the mean for all males. These monkeys did not differ significantly in age or body weight from each other or the remaining males in the study, but 5 of the 7 monkeys with high STC were high-ranking in the group and 7 of 8 monkeys with STC (115.6 +/- 5.8 mg/dl) 1 SD or more below the mean for all males were low-ranking. The difference was significant (p less than .05, Fisher's Exact Test).