Frequency of spontaneous congenital defects in rhesus and cynomolgus macaques

Abstract

This paper summarizes the spontaneous incidence of congenital defects in the rhesus and cynomolgus macaque colonies (Macaca mulatta and M. fascicularis) at the California Regional Primate Research Center. The computerized database used in this analysis included fetuses, term infants, juveniles, and adults that underwent a necropsy procedure over a 14-year period (1983-1996). The calculated malformation rates were 0.9% (40/4,390) and 0.3% (3/965) for the rhesus and cynomolgus monkey, respectively. Most of the observed malformations in both species affected the musculoskeletal and the cardiovascular systems, while a smaller number of defects were observed in the gastrointestinal, urogenital, endocrine, and central nervous systems. Inbreeding did not contribute to the spontaneous malformation incidence and there was no predilection for sex (male vs. female) or housing (indoors vs. outdoors) among the malformed cases. This spontaneous malformation database in our macaque colony aids in the interpretation of defects that occur in an experimental study as well as in the ongoing assessment of a healthy nonhuman primate breeding colony.

Maternal Behavior and Infant Congenital Limb Malformation in a Free-Ranging Group of Macaca fuscata on Awaji Island, Japan

“…Lapin and Yakovleva (1963) reported similar results, with a 0.48% congenital malformation rate and one individual with CLMs (Morris, 1971). Hendrickx and Prahalada (1986) and Peterson et al (1997) each found 1 case of CLM in 1698 (0.06%) and 4390 (0.02%) necropsies, respectively, conducted on captive rhesus macaques at the California Regional Primate Center. Two subsequent cases of CLM were reported at the same facility (Brignolo et al, 2002).…”

Developmental and reproductive toxicology studies in nonhuman primates

“…Because of the single births, low fertility rates, and high spontaneous abortion rates, enlarging the group sizes for these studies based on statistical power is not practical or appropriate. In spite of these limitations of the model, developmental toxicity studies in NHPs have provided a high level of predictivity of human teratogens (Schardein et al, 1985), perhaps related to the low background incidence of malformations in NHPs (Peterson et al, 1997). It should be recognized that the purpose of these studies is to identify the hazard, but they may not be appropriate for use in risk assessment.…”

Conjoined twins in a rhesus monkey (Macaca mulatta)

“…To our knowledge, there has been only one previous case of conjoined twins reported in Old World macaques. This case involved cranial duplication in nonviable term rhesus monkey infants in our breeding colony [10].…”