Initiation and solicitation in male-female grooming in a wild Japanese macaque troop on yakushima island

Grooming initiation among adult males and females of a Japanese macaque troop was analyzed during the non-mating season. Some gestures (“solicitation”) elicited grooming from partners at a high rate. Grooming initiation patterns were divided into two main types: (1) a male often solicited a female to groom him immediately after approaching her and was groomed by her; and (2) a female approached an alpha male selectively, and immediately groomed him. After a female groomed a male, she rarely solicited him to groom her and instead often moved away from him. These results indicated that males were motivated to be groomed, while females were more highly motivated to groom. Sex differences in grooming motivation can be explained by sex differences in the benefit to be groomed.     

Seroprevalence of B virus (Herpesvirus simiae) antibodies in a naturally formed group of rhesus macaques

Eighty-two percent of a group of rhesus monkeys removed from Cayo Santiago were seropositive for B virus (Herpesvirus simiae) antibodies. Similar results were obtained from the Cayo Santiago macaque population two decades ago and from feral Indian rhesus monkeys. Thus it is likely that B virus has been enzootic in the Cayo Santiago population since 1938, when the colony was established with stock imported from India.     

Effects of social and inanimate enrichment on the behavior of yearling rhesus monkeys

Certain types of inanimate environmental enrichment have been shown to positively affect the behavior of laboratory primates, as has housing them in appropriate social conditions. While social housing is generally advocated as an important environmental enhancement, few studies have attempted to measure the influence of social conditions on the effects of inanimate enrichment or to compare the relative merits of social and inanimate enhancements. In the present study, inanimate enrichment (predominately physical and feeding enhancements) resulted in increased species-typical behavior for socially restricted subjects. However, social enrichment (living in groups) appeared to be more beneficial for young rhesus monkeys, leading to increased species-typical activities and decreased abnormal activities. The behavior of one cohort of yearling rhesus monkeys (Macaca mulatta) housed in small peer groups was compared with the behavior of four yearling cohorts housed in single cages. Half the animals in each cohort received a three-phase enrichment program and the rest served as controls. Group-housed yearlings spent significantly more time feeding and exploring and significantly less time behaving abnormally, self-grooming, and drinking than did singly housed yearlings. Enriched subjects spent significantly more time playing by themselves, and significantly less time self-grooming and exploring than did controls. Among group-housed subjects only, there were no differences between enriched and control monkeys. Captive primates should be housed socially, whenever appropriate, as the first and most important step in an enrichment program, with the provision of inanimate enhancements being considerably less important. Limited resources for inanimate enrichment programs instead should be focused on those individuals who can not be housed socially. © 1996 Wiley-Liss, Inc.     

两种颚口线虫流行病学调查和刚刺颚口线虫幼虫对四十种动物感染力的研究

本文报告刚刺颚口线虫Gnathostoma hispidum和棘颚口线虫Gnathostoma spinigerum流行学和动物实验。证明我国有40种动物充当它们的第一、二中间宿主和转续宿主,其中30种是这两种病源共同宿主。首次报告猕猴Macaca mulatta可作刚刺颚口线虫的第二中间宿主和转续宿主。用刚刺颚口线虫晚第三期幼虫经皮肤感染家猫和小白鼠均得阳性。调查和实验结果表明刚刺颚口线虫和棘颚口线虫的生物学和流行学特性十分相似,显示它们都是人兽共患的寄生虫。文中讨论刚刺颚口线虫的传播途径和人体感染问题。     

Variation in Intergroup Encounters in Two Populations of Japanese Macaques

The nature of intergroup encounters differed between two populations of wild Japanese macaques (Macaca fuscata): the Yakushima and Kinkazan populations. In the Yakushima population, intergroup encounters were more likely to result in the displacement of one group, intergroup agonistic interaction was common, and intergroup dominance was usually distinct. When displacement occurred at Yakushima, larger groups tended to dominate smaller ones. Conversely, in the Kinkazan population, intergroup encounters rarely resulted in displacement, intergroup agonistic interaction was rare, and intergroup dominance was usually unclear. Thus, monkeys in Yakushima appear to defend resources actively during encounters, while those in Kinkazan usually did not defend resources. The frequency of encounters was significantly higher in Yakushima than in Kinkazan. The two populations had very different group densities and traveling speeds, both of which directly influence the chance of encounters. Taking these differences into account, we compared the observed frequency with those predicted by the ideal gas model. The observed frequencies in both populations were about one-third of the number expected with the model, which suggests that the differences in encounter frequency were caused by differences in group density and traveling speed. We discuss this intraspecific variation in light of economic defendability in connection to habitat differences and the evolutionary significance of resource defense behavior.     

分子标记在猕猴遗传多样性研究中的应用

分子标记目前已成为研究遗传多样性的主要工具,为此,简要综述了几种常用的分子标记(RFLPs、RAPD、mtDNA、微卫星DNA、SNPs)的检测方法及其在猕猴种群遗传多样性研究中的应用,为国内猕猴遗传多样性的研究提供参考。     

Reproductive strategies of rhesus macaques

Reproductive strategies incorporate a multitude of mechanisms that have evolved to promote the reproductive success of individuals. Evolutionary perspectives tend to emphasize the advantages of male-male competition and female choice as mediators of differential reproduction. Male rhesus macaques have not been observed to fight for access to sexually receptive females, although they suffer more wounds during the mating season. An increased likelihood of attacks appears to coincide with male troop entry. Males who spend more time in consort and mate with more females tend to sire more offspring. Genetic analysis of paternity has pinpointed age and endurance rivalry, rather than agonistic competition, as key variables associated with variation in progeny production. Female rhesus macaques often copulate with multiple males during their ovulatory period, and tend to conceive on the first cycle of the mating season. Female reproductive success is more likely to be a function of offspring survivorship than the identity of particular male partners. The role of female choice as a direct mediator of male reproductive success is unresolved, but female mate selection seems to indirectly affect male reproductive success because female preference for mating with novel males seems to foster male dispersal. Evaluating whether mating preferences for particular male phenotypes affectsfemale reproductive success is a task for the future. A common denominator to the reproductive strategies of both female and male rhesus macaques is that feeding patterns affect body condition which influences reproductive output and regulates relative reproductive success.     

A ten-month study of endogenous testosterone levels and behaviour in outdoor-living female rhesus monkeys (Macaca mulatta)

Endogenous testosterone levels were measured in association with sexual, aggressive, and social/affiliative behaviors in 11 outdoor-housed female rhesus monkeys over a ten-month period. Several behaviors (sex directed toward the male, sex received from the male, aggression directed toward the male, submission directed toward the male, submission directed toward the female, and groom another female) were significantly (p<0.05) positively correlated with testosterone in from one to five females. No trends were strong enough across all females to suggest that any of these correlations have species-wide significance. Factor analysis revealed clearcut clusters of behaviors, but elevations in testosterone were not strongly associated with any of these clusters. It is concluded that endogenous testosterone levels have little measurable effect on overt behavior in female rhesus monkeys.     

恒河猴群微卫星DNA多态性的分析

目的　确立一种对恒河猴群个体的遗传物质进行准确可靠、快速简便的遗传检测方法。方法　利用聚合酶链反应 (PCR)扩增技术对 2 0只恒河猴群个体间进行了DNA多态性的分析。结果　筛选出 9个微卫星DNA位点具有显著多态性 ,4个微卫星DNA位点没有多态性 ,还有 2个位点等位基因数目较少。结论　利用这些多态性微卫星位点建立一种对恒河猴群个体进行有效、准备可靠、快捷简便的遗传背景监测方法。