Age as a determinant of reproductive success among captive female rhesus macaques (Macaca mulatta)

Abstract

A retrospective analysis was performed on fertility outcomes among a colony of captive Indian rhesus monkeys. The analysis covered over 30 years and was based on 1443 females with a total of 11 453 pregnancies. Various determinants of fertility were assessed including birth rates, pregnancy loss, infant survival, interbirth intervals, and interval from last birth to death. Binary variables were analyzed with generalized linear models with random intercepts, while linear mixed models were used for analysis of continuous variables. Age of the dam was a significant factor in determining whether a pregnancy resulted in a birth and whether an infant survived the first 30 days with primiparous or older mothers being less likely to produce an infant surviving to that age. In contrast, sex proved to be the only significant factor in determining whether an infant lived to 1 year, with females being more likely to survive. The interval between births proved to be affected primarily by dam age, while the late death of an infant depressed the likelihood of an extended time interval between her last birth and her death. Overall, these results demonstrate that maternal age contributes significantly to a decline in fertility and older females can live relatively long periods following birth of their last infant.

Determinants of Reproductive Performance Among Female Gray-Cheeked Mangabeys (Lophocebus albigena) in Kibale National Park, Uganda

“…macaques (Gagliardi et al 2007;Hoffman et al 2010), mountain gorillas (Gorilla beringei: Robbins et al 2006), and Barbary macaques (Paul et al 1993). …”

Increasing Age Influences Uterine Integrity, But Not Ovarian Function or Oocyte Quality, in the Cheetah (Acinonyx jubatus)1

“…Specifically, for primate and murine models, an accelerated loss of oocytes takes place near the onset of reproductive senescence, occurring coincidentally with irregular and protracted cycles [17,19], decreases in oocyte number [17,19] and quality [20], and sharp declines in fecundity [21,22]. Circulating follicle-stimulating hormone (FSH) and luteinizing hormone (LH) concentrations also rise as the transition to senescence nears in humans [23] and nonhuman primates [17,24], whereas estrogen [24,25] and progesterone concentrations [25] decrease markedly.…”

Early amygdala or hippocampus damage influences adolescent female social behavior during group formation.

“…This is a particularly important time in the lives of female mammals who typically begin to reproduce and raise young. Rhesus macaque females become sexually mature around 3–4 years of age and typically begin to become pregnant and give birth soon thereafter (Kaufmann, 1965; Wilson, Gordon, Blank, & Collins, 1984; Smuts, Cheney, Seyfarth, Wrangham, & Struhsaker, 1987; Anderson & Simpson, 2007; Gagliardi, Liukkonen, Phillippi-Falkenstein, Harrison, & Kubisch, 2007, Stephens & Wallen, 2013). To meet these developmental milestones, young females are tasked with securing a mating partner by forming temporary, but strong, social bonds with sexually reproductive males.…”