The Histology of Background Pathological Processes in Cynomolgus Monkeys (Macaca fascicularis) from Control Groups in Toxicology Studies

Histological samples of organs obtained from 72 (35 male and 37 female) cynomolgus monkeys (M. fascicularis) negative control groups in 12 toxicological studies were analyzed retrospectively. The most common processes where focal accumulations exogenous pigment found 76.4% animals the lungs, non-atrophic chronic gastritis, which was observed 37.4% animals, quiescent colitis noted 36.1% cases, infiltrate liver 33.3% gastritis identified 30.5% lymphoplasmacytic infiltrates kidneys 26.4% animals. Identification accumulation information on background pathology findings primates are essential since these data allow differentiating spontaneous abnormalities associated with administration a drug test, to correctly interpret results toxicology studies.