Toxicity of Nerium oleander in the Monkey (Cebus apella)

Abstract

The toxic effects of Nerium oleander were evaluated in capuchin monkeys ( Cebus apella) by examination of clinical signs, hematologic and serum chemical values, and gross and microscopic lesions. Dried and ground oleander leaves were given at intervals of 48 h in doses of 30, 7.5, and 3 mg/kg body weight. The cumulative lethal dose ranged from 30 to 60 mg/kg body weight in monkeys that were given doses of 30 and 7.5 mg/kg body weight. Monkeys that received doses of 3 mg/kg body weight (total cumulative dose: 60 mg/kg) survived. Clinical signs were vomiting, salivation, polyuria, bradycardia, vaginal hemorrhage, abortion, anorexia, constipation, loss of body weight, narcosis, restlessness, weakness, and shallow and rapid respirations. Changes in blood values were leukocytosis; neutrophilia; increased potassium, glutamic-oxalacetic transaminase, glutamic-pyruvic transaminase, blood urea nitrogen and α-globulins; reticulo-cytopenia; and decreased calcium, glucose, total serum protein, albumin, γ-globulin levels and albumin-globulin ratios. Hemorrhages, degeneration, or necrosis, or all of these, were observed in the heart, gastrointestinal tract, skeletal muscles, ovaries, adrenal glands, liver, kidneys, and pancreas. The organ weights of the pancreas were significantly reduced. Adrenal weights were significantly increased in monkeys that received the highest dose level.