Spontaneous Vitiligo in a Captive Rhesus Monkey ().

Vitiligo affects a significant portion of human and animal populations. The disease causes irregular and multifocal progressive loss of fur, skin, and mucous membrane pigmentation due to the loss or absence of melanocytes. While etiopathogenesis is not completely understood, autoimmunity, environmental, and genetic factors are implicated We present a case report on a 16-y-old female rhesus macaque ( ) with depigmented areas that are progressively increasing on the skin and coat and are distributed on the head and back.

Cleft lip and palate associated with other malformations in a neotropical primate (Saimiri ustus).

Cleft lip (with or without cleft palate) has been documented in several species of nonhuman primates, which in general are susceptible at similar doses and stages of gestation to the same teratogens as humans. Cleft lip can be unilateral or bilateral, isolated, syndromic, familial, or genetic. Here we report the first case of syndromic cleft lip and palate in a male bare-eared squirrel monkey (Saimiri ustus).

Variation in clitoral length in rhesus macaques (Macaca mulatta).

Clitoromegaly in the neonatal period is an important morphologic sign that can be useful for sexual determination in aberrant cases. In rhesus monkeys, differentiation of the external genitalia occurs early during gestation (at 55 to 60 d) and is complete by approximately 80 d. Most of the critical steps in genital differentiation in primates occur prenatally.

Studies on argyrophilic nucleolar organizer regions (AgNORs) in a spontaneous mammary gland ductal carcinoma of a captive rhesus monkey.

A spontaneous mammary gland ductal carcinoma was diagnosed in a 13-year-old female captive rhesus monkey (Macaca mulatta). The expression of argyrophilic nucleolar organizer regions (AgNORs) was studied to investigate the correlation between the histologic invasiveness and cell proliferation activity assay for predicting the biologic behavior of this tumor type. The results of this study show that the AgNOR size in tumor cells reflect the degree of malignancy when compared with the pattern of peripheral blood lymphocytes of the same individual.