Use of nonhuman primates in cancer research

A short historical review of the use of primates in cancer research is presented followed by a review of various forms of neoplasma observed in the oldest existing Primate Center. Special attention is paid to baboon lymphomas studied for the past two decades at the U.S.S.R. Primate Center at Sukhumi.     

Genetic Management of Captive and Reintroduced Bilby Populations

Captive breeding and translocation, whereby selected individuals are used to supplement or re-establish failing populations, are powerful tools for conserving threatened fauna. These tools, however, are rarely successful at establishing self-sustaining populations that can survive without ongoing human assistance. The maintenance of genetic diversity and demographic security in captivity, or following wildlife translocation events, is important for improving the long-term effectiveness of threatened species recovery efforts around the world. Routine population monitoring using hypervariable genetic markers represents a promising technique for evaluating the effect of established management practices on population structure and genetic diversity across various spatial and temporal scales. In this study, we employed a data set of 1,068 single nucleotide polymorphisms to conduct a comprehensive survey of population structure and genetic diversity in greater bilbies (Macrotis lagotis) held at 13 zoos and wildlife sanctuaries across Australia between August 1996 and December 2016. We observed significant genetic structuring across the study sites, consistent with the limited exchange of animals between independently managed facilities. The majority of variation, however, still occurred at the level of individual bilbies (75%, P < 0.001). We also uncovered evidence for an ongoing loss of genetic diversity in some conservation-fenced populations, despite a slight excess of heterozygosity across the sampling sites as a whole. Maintaining the genetic health of bilbies in captivity or following translocation will therefore require stakeholders to focus on reducing individual mortality, and maintaining genetic connectivity across all existing populations through the regular exchange of selected individuals. As such, admixture is expected to play an increasingly important role in future conservation programs. © 2019 The Authors. Journal of Wildlife Management published by Wiley Periodicals, Inc. on behalf of The Wildlife Society.     

Individual differences in temperament and behavioral management practices for nonhuman primates

Effective behavioral management plans are tailored to unique behavioral patterns of each individual species. However, even within a species behavioral needs of individuals can vary. Factors such as age, sex, and temperament can affect behavioral needs of individuals. While some of these factors, such as age and sex, are taken into account, other factors, such as an individual's temperament, are rarely specifically provided for in behavioral management plans. However, temperament may affect how animals respond to socialization, positive reinforcement training and other forms of enrichment. This review will examine how individual differences in temperament might affect, or be affected by, behavioral management practices for captive primates. Measuring temperament may help us predict outcome of social introductions. It can also predict which animals may be difficult to train using traditional methods. Further, knowledge of temperament may be able to help identify individuals at risk for development of behavioral problems. Taken together, understanding individual differences in temperament of captive primates can help guide behavioral management decisions.     

Varicella-like herpesvirus infections of nonhuman primates

At least three distinct herpesviruses cause varicella like exanthematous diseases among nonhuman primates. Spontaneous epizootics have resulted in high morbidity and mortality rates among Cercopithecus aethiops, Erythrocebus patas and Macaca species in research colonies. Mild infections have been observed in infant chimpanzees and a gorilla. This group of diseases is of interest not only because they are a threat to primate colonies, but also because their pathologic similarity to progressive human varicella makes them a potentially valuable animal model of this disease. The nonhuman primate varicella-like exanthematous diseases are reviewed and compared to varicella in man.     

Locomotor diversity in prosimian primates

An understanding of prosimian movement is basic to many anatomical and paleontological studies in that these studies attempt to correlate movement with anatomy and therefore infer movement in fossil primates. Duke University has a large and diverse collection of prosimian primates, which are housed in cages and enclosures large enough for movement studies. Extant prosimians move in many different ways, and none are so specialized that only one mode of travel is used. The most general locomotor patterns are observed for the cheirogaleids, and thus theirs may best resemble the locomotor patterns of the ancestral euprimate.     

Nephroblastomatosis and nephroblastoma in nonhuman primates

Wilms' tumors, or nephroblastomas, are renal embryonal malignancies with a high incidence in humans. Nephroblastomas are uncommon in nonhuman primates. This report describes three cases of spontaneous proliferative renal tumors in young monkeys: two cases of unilateral kidney nephroblastomas in baboons and a nephroblastomatosis in a cynomolgus macaque. Histologically, both baboon tumors were typical of Wilms' tumors found in humans, with proliferative epithelial cells forming tubules and aborted glomeruli, nephrogenic rests and proliferative fibrovascular tissue. The left kidney of the macaque was markedly enlarged and histologically similar to the baboon tumors, although normal kidney architecture was completely effaced by primitive tubules and occasional glomeruli surrounded by edematous stromal tissue. Cytogenetic analysis did not detect any macaque or baboon equivalents to human Wilms' tumor chromosomal abnormalities. By human pathology classification, the diffuse nature of the macaque tumor is more consistent with nephroblastomatosis than nephroblastoma. This differentiation is the first to be reported in a species other than human. The nephroblastomas described here are the first nephroblastomas to be reported in baboons. Our observations indicate that nonhuman primate nephroblastomatosis and nephroblastomas develop in a similar way to Wilms' tumors in humans, although no genetic marker has been associated with nephroblastomas of nonhuman primates thus far.     

Diabetes mellitus in nonhuman primates: recent research advances and current husbandry practices

Primates can be utilized for a variety of studies to give insight into the mechanisms of the onset and progression of diabetes mellitus and obesity, and into the development of secondary manifestations. Results can be used to understand the etiologies and effects of diabetes in human beings. Investigators and animal care personnel should be continually aware of the potential for development of diabetes among primates and should seek to identify the earlier stages before the appearance of overt diabetes. In addition to updating recent research in which nonhuman primates have been used in studies on the different forms of diabetes, this review also furnishes some information about therapeutic management and husbandry of monkeys with predispositions toward diabetes or with overt diabetes.     

Association between hybrid status and reproductive success of captive male and female rhesus macaques (Macaca mulatta) at the California National Primate Research Center (CNPRC)

The California National Primate Research Center (CNPRC) houses more than 1,000 rhesus macaques (Macaca mulatta) of mixed Chinese-Indian ancestry. Most of these animals are kept in outdoor field cages, the colony's long term breeding resource. Since 2001, hybrids comprised between 4 and 49% of the field cage populations, but in most cases have represented a maximum of 10% of those populations. The increasing prevalence of hybrids is partly due to management efforts to distribute genetic diversity effectively and minimize genetic subdivisions. However, other factors may also contribute to the spread of hybrids within the colony, most notably variance in socio-sexual behaviors and physical attributes. It is known that hybrids of some species exhibit heterosis, such as early maturation, that can enhance reproductive success, and anecdotal observations of mixed groups of hybrid, Indian and Chinese animals at the CNPRC suggest that hybrids are more sexually active. To determine whether hybrids experienced a reproductive advantage, a study was conducted using birth records of 5,611 offspring born in the CNPRC colony between 2003 and 2009. We found that while the degree of Chinese ancestry (DCA) appeared to influence the maturational schedule of both males and females (maturation was inversely related to proportion of Chinese ancestry), DCA had no independent effect on either male or female RS or rank. Therefore, we have found no evidence that a hybrid phenotype confers an absolute reproductive advantage in our colony.     

In vitro fertilization in nonhuman primates

Ovulation induction, sperm capacitation, and fertilization have been studied for over 50 years in nonhuman primates but it has only been in the past 20 years that extensive studies on sizeable numbers of embryos have been carried out. Of over 200 species of nonhuman primates only a few have been studied and the majority of the findings come from studies of the squirrel monkey, baboon, rhesus, and cynomolgus macaque. Nevertheless, the fertilization process appears to be similar to that identified in other mammals and in man.     

Sociophysiology of well-being in nonhuman primates.

Knowledge of neuroendocrine responsiveness can provide insights into the social and physical conditions that promote well-being in captive primates. Activity and reactivity of stress response systems provide information regarding the degree to which animals are prepared for motoric expression, the kinds of situations that lead to mobilization of resources, and susceptibility to common clinical disorders. Social relationships can alter activity and reactivity of stress response systems. In some instances, social relationships can influence well-being by increasing or decreasing stress responsiveness. Other types of social relationships can influence well-being by altering homeostatic processes that regulate activity and reactivity of neuroendocrine systems. When the breadth of social and physiologic processes is considered, sociophysiologic contributions to well-being are more pervasive than has hitherto been considered.     

Digestive enzymes of human and nonhuman primates

All living organisms need to consume nutrients to grow, survive, and reproduce, making the successful acquisition of food resources a powerful selective pressure. However, acquiring food is only part of the challenge. While all animals spend much of their daily activity budget hunting, searching for, or otherwise procuring food, a large part of what is involved in overall nutrition occurs once the meal has been swallowed. Most nutritional components are too complex for immediate use and must be broken down into simpler compounds, which can then be absorbed by the body. This process, digestion, is catalyzed by enzymes that are either endogenous or produced by the host's microbial population .¹ Research shows that the nutritional value of food is partially constrained by the digestive abilities of the microbial community present in the host's gut and that these microbes rapidly adapt to changes in diet and other environmental pressures .² An accumulating body of evidence suggests that endogenously produced digestive enzymes also have been, and still are, common targets of natural selection, further cementing their crucial role in an organism's digestive system .^3–5     

非人灵长类的亲缘选择

亲缘选择是动物进化的重要研究领域之一,非人灵长类因具有丰富的社会网络,是亲缘选择研究领域的重要类群。动物进行亲缘选择的前提是亲缘识别,并常通过社会行为的亲缘偏向表现。因此,本文从非人灵长类的亲缘识别机制和亲缘关系对其社会行为的影响两方面进行了综述:熟悉性和表现型匹配是目前普遍认同的非人灵长类亲缘识别机制,同时这两种机制并不相互排斥,它们可能共同在灵长类的亲缘识别中起作用;在非人灵长类中,亲缘关系是影响社会行为模式的主导因子,它影响着多种灵长类个体的友好行为、攻击行为和性行为的选择,同时亲缘偏向行为在不同物种中表现不尽相同,说明亲缘选择理论可以部分解释灵长类的行为,但存在一定的局限性。本文分析了两种亲缘识别机制的异同以及在实际研究中利用亲缘选择理论解释非人灵长
类社会行为的局限及可能原因。目前,对非人灵长类社会中的亲缘选择研究正逐步深入,其中分子遗传学技术的应用是重要的推动力量。同时,依然存在诸如汉密尔顿规则参数估计和新大陆猴的亲缘选择研究案例的难点,有待研究者进一步探究。