Assessment of Skeletal Growth and Maturation of Premature and Term Macaca nemestrina

Abstract

Primate nurseries have traditionally collected weight and intake data to construct growth norms for their populations. The purpose of this paper is to suggest supplementing these data with skeletal maturation and linear body growth information. Methods of assessment used at the Infant Primate Research Laboratory at the University of Washington are presented, using as an example a current study which contrasts the physical growth and ossification status of premature and term-gestation pigtail macaques (Macaca nemestrina). The postnatal growth and development of the macaque is of special interest as a model for the human infant. The fetal and infant growth of the macaque is similar to the human skeletal growth and maturation process (Kerr, 1975; Newell-Morris and Tarrant, 1978). Hand and foot ossification is much more rapid than in the human, reducing follow-up time for the appearance of round bones and epiphyses to months instead of years of postnatal age. Previous studies have indicated the value of ossification onset and increments as measures of skeletal maturity (Pryor, 1906; Flory, 1936; Garn and Rohmann, 1959, 1968; van Wagenen and Asling, 1964; Kerr, 1975). Skeletal growth and ossification assess­ment can provide a more detailed picture of infant maturation status than age estimates and weight alone and may have predic­tive value for later growth and development.