Directional asymmetry in the forelimb of Macaca mulatta

Asymmetry was investigated in the forelimbs of 150 rhesus monkey (Macaca mulatta) skeletons using measurements of right and left humerii, radii, ulnae, second metacarpals, and femora. Seven of the ten forelimb dimensions were larger on the right than on the left side. Paired t-tests revealed that the mean of the right side was significantly larger than that for the left for two measurements of the ulna and two of the humerus. No measurement was significantly larger on the left than on the right side. These results indicate a small but significant asymmetry in the forelimb bones of rhesus monkeys and, as is the case for humans, the direction of asymmetry favors the right side. Our findings are consistent with an interpretation of hypertrophy of certain muscles and opens the question of whether rhesus monkeys preferentially use their right forelimbs for manipulative tasks that require manual dexterity, as is the case for humans. These forelimb skeletal asymmetries are discussed in light of the recent literature on cortical asymmetry and handedness in nonhuman primates.     

Corneal biometrics of the rhesus monkey (Macaca mulatta)

Keratometry, retinoscopy, horizontal diameter, and pachymetry were measured in adult and infant rhesus monkeys (Macaca mulatta). The adult monkeys had a mean corneal thickness of 0.47 +/- 0.03 mm (+/- standard deviation), corneal diameters of 10.6 +/- 0.5 mm, keratometry values of 51.90 +/- 1.61 diopters, and subjective refractions of 0.48 +/- 2.36 diopters. Female adult monkeys had smaller corneal diameters by 0.06 mm (P = .02) and steeper corneas by 0.77 diopters (P = .04). Infant female monkeys also had steeper corneas by 2.37 diopters (P = .05). No significant differences were found between right and left eyes in either adult or infant monkeys.     

Expression of SWAP-70 in the uterus and feto-maternal interface during embryonic implantation and pregnancy in the rhesus monkey (Macaca mulatta)

SWAP-70 is a unique signaling protein involved in multiple processes including lymphatic cell activation, migration, adhesion, and cytoskeleton organization. Its role in reproductive system remains to be unclear. In the present study, the spatial and temporal expression of SWAP-70 in the uterus during normal menstrual cycle as well as on the feto-maternal interface during pregnancy was investigated in the rhesus monkey by in situ hybridization and immunohistochemistry. It was shown that SWAP-70 was mainly expressed in glandular epithelial cells of uterine endometrium, and the level peaked at the mid-secretory stage. At the beginning of embryonic implantation, SWAP-70 was intensely expressed at the implantation site, mainly localized in glandular and luminal epithelial cells, as well as in primary trophoblasts and epithelial plaque. High level of SWAP-70 was observed in villous cytotrophoblast (VCT), syncytiotrophoblast (ST), column cytotrophoblast, trophoblast shell, interstitial trophoblast, and endovascular trophoblast during gestational days 15–25. From gestational day 50 to term, expression of SWAP-70 decreased evidently and was restricted in VCT cells. What’s more, SWAP-70 co-localized with F-actin on the feto-maternal interface, especially in highly motive extravillous trophoblasts. The data indicate that SWAP-70 may be involved in regulating motility of trophoblast cells during embryonic implantation and placentation.     

Reproductive performance in capture-acclimated female rhesus monkeys (Macaca mulatta)

Behavioral and physiological data were collected over a three-year period on a colony of compound-housed rhesus monkeys (Macaca mulatta) to examine endocrine influences on sexual behavior. The reproductive performance of the experimental animals was compared to controls which were not routinely handled. The groups did not differ significantly with regard to the percentage of conceptions or other parameters of reproductive biology. The demonstration that manipulations attendant to data collection did not jeopardize reproductive success has important implications for research on primate colonies which are maintained primarily for breeding purposes. Additionally, female copulatory behavior was found to be a reliable indicator of ovulation which allows for an accurate prediction of the parturition date.     

Comparison of electrostimulation methods for semen recovery in the rhesus monkey (Macaca mulatta)

Electroejaculation of 17 rhesus monkeys was performed at intervals during a 15-month period using both penile and rectal probe stimulation. The semen quality was compared for the two stimulation methods. Both methods were effective in approximately 90% of attempts, and there was no difference in fertilizing capacity of the sperm. A seasonal difference in semen quality was detected, and samples recovered by penile stimulation showed higher sperm count.     

Consortships and conceptions in captive rhesus macaques (Macaca mulatta)

A captive group of rhesus macaques (Macaca mulatta) was observed during the breeding season to determine if consortship behavior, rather than promiscuous matings, resulted in higher reproductive success for either partner. The 38 adult females in this group were observed “in consort” with the 5 adult or 4 subadult males on 179 occasions. Most of these consortships were short-term, lasting less than one day. Six females engaged in consortships with one male that spanned more than three days, but the majority of these long-term associations did not result in a pregnancy with that male. The term “consortship” has been traditionally accepted as a specific nonhuman primate mating pattern, but the exact nature of this behavioral pattern and its evolutionary importance have been less clearly understood. Consort behavior could be considered a precursor to a monogamous mating system if long-term exclusive sexual associations resulted in higher reproductive success for the participants. But this study demonstrates that for rhesus macaques, who exhibit both consort behavior and more promiscuous matings, there is no clear reproductive advantage to long-term consortships. In light of the inconsistent use of the term consortship, the possible adaptive significance of an exclusive male-female sexual association for the evolution of human mating patterns needs to be reevaluated.     

Species discrimination and concept formation by rhesus monkeys (Macaca mulatta)

There are 19 species in genusMacaca and some of them are living in sympatry (Fooden, 1980). Although inter-specific hybrids are relatively easy to produce under artificial conditions, hybridization does not occur naturally. What is preventing that among the species of genusMacaca? Three rhesus monkeys acquired a discrimination between pictures with rhesus monkeys and without rhesus monkeys. All subjects showed positive transfer of this discrimination to new pictures with rhesus monkeys and without rhesus monkeys. A further test showed that these monkeys could discriminate between pictures of rhesus monkeys and pictures of Japanese monkeys. The results suggest that rhesus monkeys recognize rhesus monkeys as a class, independent of the actual stimuli such as a picture or an individual monkey. The ability to recognize members of their own species and the opportunities for such learning may be an important factor preventing hybridization among the species of genusMacaca.     

Early maternal recognition of offspring vocalizations in rhesus macaques (Macaca mulatta)

This study investigated the development of maternal recognition of infant calls in rhesus macaques (Macaca mulatta). Fifteen mothers and their offspring, of age ranging from several hours to 28 days, served as subjects of an experiment in which the offspring's distress vocalizations were recorded and then played back to their mothers simultaneously with those of an age-matched control infant. The proportion of time looking at, but not the proportion of orientations to the speaker playing the offspring's vocalizations increased significantly as a function of infant age. Specifically, mothers of infants older than 1 week of age responded longer to the playback of their own infant's calls than did mothers of younger infants. These findings provide the firt evidence that offspring recognition in macaques develops between the first and second week of the infant's life and are consistent with the hypothesis that mothers need to be exposed to their infants' calls in order to learn their acoustic characteristics.     

Comparative teratogenicity of triamcinolone acetonide and dexamethasone in the rhesus monkey (Macaca mulatta)

Pregnant rhesus macaques were treated with 0.5 or 2.5 mg/kg triamcinolone acetonide (TAC) or 1.0 or 10.0 mg/kg dexamethasone sodium phosphate (DEX) between 20 and 50 gestational days (GD). Treatment with TAC at 2.5 mg/kg resulted in a fetal loss of 71%; 3/5 recovered fetuses displayed an encephalocele or meningocele. All other treatment groups displayed minor cranial skeletal abnormalities consistent with glucocorticoid-mediated teratogenesis. DEX was shown to have a lower teratogenic potential than TAC in this species.     

Pott's Paraplegia in a Tuberculous Rhesus Monkey,Macaca mulatta

Thirty-eight young adult Rhesus monkeys (Macaca mulatta) gave negative reactions to four consecutive intrapalpebral tuberculin testings at 2-week intervals. Shortly afterwards, one of six subsequently found to have tuberculosis caused by Myobacterium tuberculosis hominis, suddenly developed dyspnea and paraplegia. Gross and histopathologic examination revealed epidural compression of the spinal cord by excessive granulation tissue originating in the 2nd and 3rd thoracic vertebrae. Neither vertebra exhibited gross structural collapse. One monkey had early generalized tuberculosis and four had pulmonary tuberculosis only. The need for unrelenting vigilance and strict control policies in primate colonies is emphasized.     

糖在猕猴精子低温冷冻保存过程中的作用

TTE或TEST防冻液在冻存猕猴精子时产生不同结果,其主要不同在于防冻液中糖成分的不同。本实验利用透射电镜技术检测这2种防冻液冻存的猕猴精子冷冻前后超微结构的变化,以说明糖在低温冻存过程中的作用。结果表明,冷冻复苏过程对精子结构产生了影响。TTE法低浊保存的猕猴精子的头部的质膜出现少许皱褶或泡化现象,但精子的顶体、核或是精子尾部的结构与鲜精的结构基本相似。猕猴精子经TEST法低温保存后,大部分精子结构则发生了明显的变化。精子膜、顶体和精子核明显泡化、损伤或破裂,精子尾部不能分辨出正常的超微结构。这提示,可能由于TTE防冻液中复杂的糖成分在降温／复苏过程对精子起到了较好的协同冷冻保护作用;而TEST防冻液中单一的糖成分不能完全保护精子避免低温损伤,低温保存过程破坏了精子的结构,并影响了复苏后精子体外存活能力与受精能力。     

Synaptic ribbon populations in the pineal gland of the rhesus monkey (Macaca mulatta)

Summary Pinealocytes of rhesus monkeys that had been ovariectomized and given intramuscular injections of 250 g estradiol-benzoate for 3 consecutive days tended to have more synaptic ribbons (SR) and exhibited a significantly greater size of ribbon fields (RF) compared to untreated animals. These data are consistent with hypotheses that pinealocyte function in primates is altered by hormonal imbalances and that the SR participates in this response. RF were positioned in various parts of the cytoplasm and along the plasma membrane. Participation of SR in direct cell-to-cell contacts was suggested by the formation of densities along the plasma membrane. It is postulated that large RF serve as storage organelles and that the formation of RF results from division of pre-existing SR in each field. Reconstructions made from serial thin sections revealed that profiles of RF comprised separate SR that were not folded and sectioned along various planes.     

The development of behavioural sex differences in infant rhesus macaques (Macaca mulatta)

Studies of infant rhesus macaques have generally reported sex differences in the frequency of expression of some behaviour patterns, such as rough-and-tumble play and socio-sexual mounting. In contrast, sex differences in other behaviour patterns, such as proximity to the mother, have been less consistantly reported. Using data on the behavioural development of infant rhesus macaques living in captive social groups, we have attempted to provide further evidence for, or against, sex differences in behaviour and to investigate the possible influence of maternal rank and parity on sex differences in infant behaviour and mother-infant interactions. The behaviour of 14 male and 20 female infants and their mothers was studied during the first six months of life, including measures of play behaviour socio-sexual mounting, and mother-infant interactions. Our data reveal that, on average, male infants exhibited more rough-and-tumble play and mounting than female infants, and also exhibited stationary play, chasing play, and initiated play more frequently than females. Such sex differences appear to be robust in macaques and have been reported in a variety of housing conditions. male and female infants did not differ in the amount of time spent at particular distances from their mothers, and mothers were not found to behave differently towards sons and daughters, using measures of restraint, rejection, and grooming. These results are in contrast to previous studies on singly-housed mother-infant pairs but similar to those on free-ranging populations. Mothers did behave differently towards their infants depending upon the mother's rank and previous number of offspring. These maternal characteristics may have significant consequences for the behavioural development of both male and female infant primates.     

Social rank and cortisol among female rhesus macaques (Macaca mulatta)

In animal societies, some stressful events can lead to higher levels of physiological stress. Such stressors, like social rank, also predict an increased vulnerability to an array of diseases. However, the physiological relationship between social rank and stress varies between different species, as well as within groups of a single species. For example, dominant individuals are more socially stressed at times, while at other times it is the subordinate ones who experience this stress. Together, these variations make it difficult to assess disease vulnerability as connected to social interactions. In order to learn more about how physiological rank relationships vary between groups of a single species, cortisol measurements from hair samples were used to evaluate the effects of dominance rank on long-term stress levels in despotic and less stringent female rhesus macaque hierarchal groups. In despotic groups, cortisol levels were found not to be correlated with social rank, but a negative correlation was found between social rank and cortisol levels in less stringent hierarchies. Low ranking monkeys in less stringent groups secreted elevated levels of cortisol compared to higher ranking animals. These data suggest that variations in the strictness of the dominance hierarchy are determining factors in rank related stress physiology. The further consideration of nonhuman primate social system diversity and the linear degree of their hierarchies may allow for the development of valid rank-related stress models that will help increase our understanding and guide the development of new therapeutics for diseases related to human socioeconomic status.     

野生猕猴（Macaca mulatta）通讯行为的初步研究

本文报道了野生猕猴通讯行为的初步研究结果。分别观察成年雌性和幼年猴的鸣叫和表情行为。猕猴正常时的表情自然轻松,有时发出一些声音。在听觉上成年雌猴的叫声为“hè”,幼年猴叫声为“ēn”,其最大共振峰频率Fmax分别为900Hz和1000Hz。猴受惊时表情紧张,双目圆睁,微张口,两嘴角外拉。成年雌猴和幼猴分别发出“kè”和“giè”的叫声,其最大共振峰频率分别为550Hz和350Hz,与正常叫声相比,惊叫声的最大共振峰频率降低,各单叫声持续的时间较短。     

Osmotic tolerance and membrane permeability characteristics of rhesus monkey (Macaca mulatta) spermatozoa

Biophysical characteristics of the plasma membrane, such as osmotic sensitivity and water and cryoprotectant permeability are important determinants of the function of spermatozoa after cryopreservation. A series of experiments was conducted with rhesus macaque spermatozoa at 23 degrees C to determine their: (1) cell volume and osmotically inactive fraction of the cell volume; (2) permeability coefficients for water and the cryoprotectants dimethyl sulfoxide, glycerol, propylene glycol, and ethylene glycol; (3) tolerance to anisosmotic conditions; and (4) motility after a one step addition and removal of the four cryoprotectants. An electronic particle counter and computer aided semen analysis were used to determine the cell volume and permeability coefficients, and motility, respectively. Rhesus spermatozoa isosmotic cell volume was 27.7+/-3.0 microm3 (mean+/-SEM) with an osmotically inactive cell fraction of 51%. Hydraulic conductivity in the presence of dimethyl sulfoxide, glycerol, propylene glycol, and ethylene glycol was 1.09+/-0.30, 0.912+/-0.27, 1.53+/-0.53, and 1.94+/-0.47 microm/min/atm, respectively. Cryoprotectant permeability was 1.39+/-0.31, 2.21+/-0.32, 3.38+/-0.63, and 6.07+/-1.1 (x10(-3)cm/min), respectively. Rhesus sperm tolerated all hyposmotic exposures. However, greater than 70% motility loss was observed after exposure to solutions of 600 mOsm and higher. A one step addition and removal of all four cryoprotectants did not cause significant motility loss. These data suggest that rhesus sperm are tolerant to hyposmotic conditions, and ethylene glycol may be the most appropriate cryoprotectant for rhesus sperm cryopreservation, as it has the highest permeability coefficient of the tested cryoprotectants.     

中国猕猴生态学研究进展

中国的灵长类学研究始于19世纪中期之后,而兴盛于20世纪80年代至今。猕猴（Macaca mulatta）是世界及中国分布最为广泛的一种非人灵长类动物,在中国境内分布于17个省（市、区）,已被列为国家二级重点保护野生动物。迄今为止,学者们已对猕猴进行了包括地理分布、种群动态、食性、社会生态、保护生态等多方面的研究。本文拟对国内有关猕猴生态学方面的研究工作进行回顾与综述,以期通过对以往工作的汇总,梳理关于猕猴的研究线索与动态,并对今后的研究有所启示。     

猕猴精子优选及体外获能的研究

选择活率高的精子并进行体外获能是开展猕猴体外受精研究的必要程序, 是研究猕猴受精生物学的重要手段。本实验采用上浮法和Percoll 梯度离心法对猕猴精液进行了优选, 并对处理后的精子形态正常率、精子活率、密度及受精率作了比较, 发现二者差异不显著; 用dbcAMP 和咖啡因使精子获能, 发现只有两种获能剂同时存在才能使猕猴精子获能并使卵母细胞受精。结论为: 上浮法和Percoll 法都是有效的精子优选法, 对受精率的影响差异不显著; dbcAMP 和咖啡因在猕猴精子体外获能时缺一不可。     

恒河猴胚胎浅表型植入机理的探讨

为揭示恒河猴胚胎浅表型植入的分子机理,实验采用免疫组化和原位杂交的方法研究了粘附侵润相关分子在妊娠恒河猴母胎界面的表达模式,发现层粘连蛋白(LN)、Ⅳ型胶原(ColⅣ)和基质金属蛋白酶-2(MMP-2)在滋养层细胞柱的远端开始表达;整合素α1β1从柱的近端到远端表达逐渐升高,但在滋养层细胞鞘中上述分子的表达均降低;大量侵润母体血管的滋养层细胞高水平表达上述分子。此外,植入早期上皮斑和蜕膜基质细胞高表达MMPs组织抑制因子-2(TIMP-2)。结果提示,滋养层细胞鞘中α1β1、LN、MMP-2表达水平的降低及上皮斑、蜕膜和滋养层细胞中TIMP-2的高表达可能是导致浅表型植入形成的分子基础。