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Macaca Mulatta (macaca + mulatta)
Selected AbstractsSex differences in juvenile rhesus macaque (Macaca mulatta) agonistic screams: Life history differences and effects of prenatal androgensDEVELOPMENTAL PSYCHOBIOLOGY, Issue 4 2005Michelle L. Tomaszycki Abstract This study investigated sex differences in juvenile rhesus macaque (Macaca mulatta) vocal behavior during agonistic contexts, and the effects of prenatal androgens on these differences. A total of 59 subjects (5,8 per treatment group) received exogenous androgen (testosterone enanthate), an anti-androgen (flutamide) or vehicle injections (DMSO) for 30 or 35 days during the second (early) or third (late) trimester of pregnancy. An additional 19 unmanipulated controls were included in the analysis. Screams by juvenile males and females between the ages of 1 and 3 years were compared to the screams of adult female exemplars using a discriminant function analysis. Juvenile females produced more adult-female like screams than did juvenile males. Females exposed to androgen treatment late in gestation produced a more masculine pattern of screams. Flutamide treatment in males either early or late in gestation did not significantly affect scream production. Flutamide treatments in females late in gestation, however, masculinized scream production. Androgen treatments administered late in gestation hyper-masculinized male scream production. No sex differences in the contextual usage of screams emerged. These findings suggest that both life history differences and the early hormone environment contribute to sex differences in juvenile rhesus macaque vocal production. © 2005 Wiley Periodicals, Inc. Dev Psychobiol 47: 318,327, 2005. [source] Rearing environment and hypothalamic-pituitary-adrenal regulation in young rhesus monkeys (Macaca mulatta)DEVELOPMENTAL PSYCHOBIOLOGY, Issue 4 2005John P. Capitanio Abstract A mammal's early social environment has important regulatory effects on its behavior and physiology, and this is especially true for regulation of the hypothalamic-pituitary-adrenal (HPA) system. The present study was designed to test hypotheses that various aspects of the social environment are important influences on HPA regulation. Seven hundred seventy eight, 3- to 4-month-old rhesus monkeys were studied as part of a standardized, 24-hr biobehavioral assessment program, which included blood sampling to determine plasma cortisol concentrations. Results indicate that nursery-rearing results in a reduced cortisol set-point for the HPA system, and, for nursery-reared (NR) animals, more peer exposure during infancy is associated with a higher set-point. Age and sex differences during this period were evident but small in magnitude. These data demonstrate the important regulatory role of the social environment on nonhuman primate physiology and suggest caution in assuming that differences between individuals' cortisol levels reflect only differences in perceptions of the "stressfulness" of events. © 2005 Wiley Periodicals, Inc. Dev Psychobiol 46:318,330, 2005. [source] Essentialism in the absence of language?DEVELOPMENTAL SCIENCE, Issue 4 2010Evidence from rhesus monkeys (Macaca mulatta) We explored whether rhesus monkeys (Macaca mulatta) share one important feature of human essentialist reasoning: the capacity to track category membership across radical featural transformations. Specifically, we examined whether monkeys , like children (Keil, 1989) , expect a transformed object to have the internal properties of its original category. In two experiments, monkeys watched as an experimenter visually transformed a familiar fruit (e.g. apple) into a new kind of fruit (e.g. coconut) either by placing a fruit exterior over the original, or by removing an exterior shell and revealing the inside kind of fruit. The experimenter then pretended to place an inside piece of the transformed fruit into a box which the monkey was allowed to search. Results indicated that monkeys searched the box longer when they found a piece of fruit inconsistent with the inside kind, suggesting that the monkeys expected that the inside of the transformed fruit would taste like the innermost kind they saw. These results suggest that monkeys may share at least one aspect of psychological essentialism: They maintain category-specific expectations about an object's internal properties even when that object's external properties change. These results therefore suggest that some essentialist expectations may emerge in the absence of language, and thus raise the possibility that such tendencies may emerge earlier in human development than has previously been considered. [source] Searching for food in the wild: a nonhuman rimate's expectations about invisible displacementDEVELOPMENTAL SCIENCE, Issue 1 2001Marc D. Hauser Five experiments involving invisible displacements were run on a population of semi-free-ranging rhesus monkeys (Macaca mulatta). The goal of these experiments was to assess, without training, the kinds of expectations individuals spontaneously set up when an object has moved out of sight. The first experiment, modeled after studies of human infants and children, involved a table with one box on the top surface and a second box lined up below on the ground. An occluder was placed in front of the table, blocking the subject's view. A piece of food was then dropped behind the occluder, above the top box. The presenter then removed the occluder, walked away, and allowed the subject to approach. Consistently, subjects searched in the incorrect bottom box. This error can be interpreted as a failure to understand solidity, containment, or some other factor. It can also be interpreted as an error guided by a gravity bias, i.e. an expectation that all falling objects fall straight down or to the lowest point. Experiments 2,5 tested these alternative hypotheses. Results show that rhesus monkeys do not have an inherent bottom box bias, are not avoiding the top box, and do recognize that in some contexts boxes can contain or hold food. Thus, for example, when the two boxes are placed on the ground, one in front of the other, and occluded, subjects search in the near box after a piece of food has been rolled behind the occluder (horizontal trajectory). This shows that rhesus can solve an invisible displacement problem that involves solid containers, where one container blocks travel to the other container. We conclude that the rhesus monkey's error in Experiment 1 is guided by an expectation that all falling objects fall straight down or, at least, to the lowest point. This expectation represents a limitation of their knowledge of physical objects and events. [source] Changes In Rhesus Macaque ,Coo' Vocalizations during Early DevelopmentETHOLOGY, Issue 10 2000Kurt Hammerschmidt In order to test whether ,coo' calls of young rhesus macaques, Macaca mulatta, undergo some modifications during early development, and to explore which factors may influence these changes, we studied the ontogeny of their contact call, the ,coo' call. Vocalizations were recorded during brief periods of social separation. Infants were either raised with their mothers and other conspecifics, or separated from their mothers at birth and housed in a nursery with other infants. We recorded calls uttered in the separation context from 20 infants. We digitized the first 50 calls of a given series and subjected them to a Fourier transform. From each frequency,time spectrum, we extracted 65 acoustic parameters using a software program (LMA 5.9). We then used a cluster analysis to separate the ,coo' calls from other call types. With increasing age, the ,coos' dropped in pitch and became more even. The course of amplitude became more constant and the call duration increased slightly. Nevertheless, we found a high intra-individual variation throughout the 5 mo. Neither rearing condition nor sex had any apparent influence on age-related changes in ,coo' structure. With one exception, all parameters that correlated with age could be explained by variation in weight. Therefore, we conclude that growth is the main factor accounting for the observed changes. [source] Intestinal double-positive CD4+CD8+ T,cells are highly activated memory cells with an increased capacity to produce cytokinesEUROPEAN JOURNAL OF IMMUNOLOGY, Issue 3 2006Bapi Pahar Dr. Abstract Peripheral blood and intestinal CD4+CD8+ double-positive (DP) T,cells have been described in several species including humans, but their function and immunophenotypic characteristics are still not clearly understood. Here we demonstrate that DP T,cells are abundant in the intestinal lamina propria of normal rhesus macaques (Macaca mulatta). Moreover, DP T,cells have a memory phenotype and are capable of producing different and/or higher levels of cytokines and chemokines in response to mitogen stimulation compared to CD4+ single-positive T,cells. Intestinal DP T,cells are also highly activated and have higher expression of CCR5, which makes them preferred targets for simian immunodeficiency virus/HIV infection. Increased levels of CD69, CD25 and HLA-DR, and lower CD62L expression were found on intestinal DP T,cells populations compared to CD4+ single-positive T,cells. Collectively, these findings demonstrate that intestinal and peripheral blood DP T,cells are effector cells and may be important in regulating immune responses, which distinguishes them from the immature DP cells found in the thymus. Finally, these intestinal DP T,cells may be important target cells for HIV infection and replication due to their activation, memory phenotype and high expression of CCR5. [source] Quantitative analysis of postnatal neurogenesis and neuron number in the macaque monkey dentate gyrusEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 2 2010Adeline Jabès Abstract The dentate gyrus is one of only two regions of the mammalian brain where substantial neurogenesis occurs postnatally. However, detailed quantitative information about the postnatal structural maturation of the primate dentate gyrus is meager. We performed design-based, stereological studies of neuron number and size, and volume of the dentate gyrus layers in rhesus macaque monkeys (Macaca mulatta) of different postnatal ages. We found that about 40% of the total number of granule cells observed in mature 5,10-year-old macaque monkeys are added to the granule cell layer postnatally; 25% of these neurons are added within the first three postnatal months. Accordingly, cell proliferation and neurogenesis within the dentate gyrus peak within the first 3 months after birth and remain at an intermediate level between 3 months and at least 1 year of age. Although granule cell bodies undergo their largest increase in size during the first year of life, cell size and the volume of the three layers of the dentate gyrus (i.e. the molecular, granule cell and polymorphic layers) continue to increase beyond 1 year of age. Moreover, the different layers of the dentate gyrus exhibit distinct volumetric changes during postnatal development. Finally, we observe significant levels of cell proliferation, neurogenesis and cell death in the context of an overall stable number of granule cells in mature 5,10-year-old monkeys. These data identify an extended developmental period during which neurogenesis might be modulated to significantly impact the structure and function of the dentate gyrus in adulthood. [source] Distinct contributions of the amygdala and hippocampus to fear expressionEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 12 2009Yogita Chudasama Abstract The present study attempted to distinguish the independent contributions of the amygdala and hippocampus to fear expression. Rhesus monkeys (Macaca mulatta) with bilateral excitotoxic amygdala lesions (n = 4), bilateral excitotoxic hippocampal lesions (n = 8) and unoperated controls (n = 9) were allowed to reach over a neutral junk object or fear-provoking stimulus (i.e., a rubber snake or a jumping rubber spider) to retrieve a food reward. Monkeys were exposed to each stimulus for 30 s. On each trial we recorded the monkey's latency to retrieve the food reward and scored their whole-body reactions to the object. Confirming previous work we found that, relative to controls, both operated groups showed shorter food-retrieval latencies and exhibited fewer defensive and more approach behaviors when exposed to the fear-provoking stimuli. However, only monkeys with amygdala lesions showed an abnormal, excessive visual interest in the snake and spider. By contrast, monkeys with hippocampal lesions displayed behaviors that were unrelated to the presence of the fear stimuli, thereby indicating a lack of interest in, and emotional reactivity towards, the snake and spider. These data show that the hippocampus and amygdala contribute independently to the overall expression of defensive responses. [source] Entorhinal cortex contributes to object-in-place scene memoryEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 11 2004David P. Charles Abstract Four rhesus monkeys (Macaca mulatta) were trained preoperatively in a test of object-in-place scene memory. They were presented daily with lists of unique computer-generated scenes each containing a spatial array of multiple individual objects. Within each scene, objects to be discriminated appeared in the foreground, each occupying a unique location, and monkeys were required to correctly discriminate the rewarded object to receive a food reward. Once this preoperative criterion was attained, the monkeys received bilateral entorhinal cortex ablation performed as either one or two surgical operations with a period of testing following each. Postoperatively, they were significantly impaired in learning new object-in-place scene problems. These results show that the entorhinal cortex, like anatomically related structures including the perirhinal cortex and the fornix, contributes to object-in-place scene learning. [source] Perirhinal cortex neuronal activity related to long-term familiarity memory in the macaqueEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 7 2003Christian Hölscher Abstract Lesion studies suggest that the perirhinal cortex plays a role in object recognition memory. To analyse its role, the activity of single neurons in the perirhinal cortex was recorded in three rhesus monkeys (Macaca mulatta) performing a delayed matching-to-sample task with up to three intervening stimuli. A set of familiar visual stimuli was used. Some neurons had activity related to working memory, in that they responded more to the sample than to the match image within a trial, as shown previously. However, when a novel set of stimuli was introduced, the neuronal responses were on average only 47% of the magnitude of the responses to the familiar set of stimuli. Moreover, it was shown in eight different replications in three monkeys that the responses of the perirhinal cortex neurons gradually increased over hundreds of presentations of the new set of (initially novel) stimuli to become as large as with the already familiar stimuli. The mean number of 1.3-s presentations to induce this effect was 400 occurring over 7,13 days. These results show that perirhinal cortex neurons represent the very long-term familiarity of visual stimuli. A representation of the long-term familiarity of visual stimuli may be important for many aspects of social behaviour, and part of the impairment in temporal lobe amnesia may be related to the difficulty of building representations of the degree of familiarity of stimuli. [source] Localization of nAChR subunit mRNAs in the brain of Macaca mulattaEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 10 2000Zhi-Yan Han Abstract We present here a systematic mapping of nAChR subunit mRNAs in Macaca mulatta brain. A fragment, from the transmembrane segments MIII to MIV of Macaca neuronal nAChR subunits was cloned, and shown to exhibit high identity (around 95%) to the corresponding human subunits. Then, specific oligodeoxynucleotides were synthesized for in situ hybridization experiments. Both ,4 and ,2 mRNA signals were widely distributed in the brain, being stronger in the thalamus and in the dopaminergic cells of the mesencephalon. Most brain nuclei displayed both ,4 and ,2 signals with the exception of some basal ganglia regions and the reticular thalamic nucleus which were devoid of ,4 signal. ,6 and ,3 mRNA signals were selectively concentrated in the substantia nigra and the medial habenula. The strongest signals for ,3 or ,4 mRNAs were found in the epithalamus (medial habenula and pineal gland), whereas there were no specific ,3 or ,4 signals in mesencephalic dopaminergic nuclei. ,5 and ,7 mRNA signals were found in several brain areas, including cerebral cortex, thalamus and substantia nigra, although at a lower level than ,4 and ,2. The distribution of ,3, ,4, ,5, ,6, ,7, ,2, ,3 and ,4 subunit mRNAs in the monkey is substantially similar to that observed in rodent brain. Surprisingly, ,2 mRNA signal was largely distributed in the Macaca brain, at levels comparable with those of ,4 and ,2. This observation represents the main difference between rodent and Macaca subunit mRNA distribution and suggests that, besides ,4,2*, ,2,2* nAChRs constitute a main nAChR isoform in primate brain. [source] Arm trajectory and representation of movement processing in motor cortical activityEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 6 2000Andrew B. Schwartz Abstract We review experiments in which single-cell primary motor cortical activity was recorded from Rhesus monkeys (Macaca mulatta) while they performed reaching and drawing tasks. The directional tuning curves generated during reaching were modulated by the speed of movement and this was reflected in the magnitude of population vectors calculated from firing rates of a large population of cells. Directional and speed representation in the firing rates of these cells is robust across both reaching and drawing. Several behavioural invariants related to the speed of drawing were represented in the time-series of population vectors. This high fidelity neural representation of velocity found in motor cortex can be used to visualize the dynamics of motor cortical activity during drawing and suggests that the cost function governing the rate of drawing is bound by neural processing. [source] Selective hippocampal damage in rhesus monkeys impairs spatial memory in an open-field test,HIPPOCAMPUS, Issue 7 2004Robert R. Hampton Abstract The hippocampus is critical for remembering locations in a wide variety of species, including humans. However, recent findings from monkeys following selective hippocampal lesions have been equivocal. To approximate more closely the situations in which rodents and birds are tested, we used a spatial memory task in which rhesus monkeys (Macaca mulatta) moved about freely in a large room, on a tether. We used MRI-guided stereotaxic surgery to produce selective hippocampal lesions in five monkeys, and retained five unoperated control monkeys. In the study phase of each trial of the matching-to-location task, monkeys found food in one site in an array of identical foraging sites. During the test, which occurred after a delay, monkeys could return to the site where the food had been found during study to obtain more food. In Experiment 1, normal monkeys showed a small significant tendency to return directly to a site where they had previously found food that day. Operated monkeys showed no such matching tendency. In Experiment 2, further training produced reliable matching-to-location performance in both groups at short delays, but monkeys with selective hippocampal lesions rapidly forgot the location of the food. In Experiment 3, we tested whether monkeys used a "cognitive map" to encode the location of the hidden food, by requiring them to relocate the food from a starting location different from that used during study. As a group, monkeys were more accurate than expected by chance, indicating that they did encode the rewarded location with respect to allocentric landmarks; however, both groups of monkeys were significantly worse at relocating the food when required to approach from a different location. In Experiment 4, probe trials using symmetrical test arrays found no evidence for egocentric coding of the rewarded location. © 2004 Wiley-Liss, Inc. [source] Rhesus macaque antibody molecules: sequences and heterogeneity of alpha and gamma constant regionsIMMUNOLOGY, Issue 1 2004Franco Scinicariello Summary Rhesus macaques (Macaca mulatta) are extensively used in vaccine development. Macaques infected with simian immunodeficiency viruses (SIV) or simian-human immunodeficiency viruses (SHIV) are the best animal model currently available for acquired-immune-deficiency-syndrome-related studies. Recent results emphasize the importance of antibody responses in controlling HIV and SIV infection. Despite the increasing attention placed on humoral immunity in these models, very limited information is available on rhesus macaque antibody molecules. Therefore, we sequenced, cloned and characterized immunoglobulin gamma (IGHG) and alpha (IGHA) chain constant region genes from rhesus macaques of Indian and Chinese origin. Although it is currently thought that rhesus macaques express three IgG subclasses, we identified four IGHG genes, which were designated IGHG1, IGHG2, IGHG3 and IGHG4 on the basis of sequence similarities with the four human genes encoding the IgG1, IgG2, IgG3 and IgG4 subclasses. The four genes were expressed at least at the messenger RNA level, as demonstrated by real-time reverse transcription polymerase chain reaction (RT-PCR). The level of intraspecies heterogeneity was very high for IGHA genes, whereas IGHG genes were remarkably similar in all animals examined. However, single amino acid substitutions were present in IGHG2 and IGHG4 genes, indicating the presence of IgG polymorphism possibly resulting in the expression of different allotypes. Two IgA alleles were identified in several animals and RT-PCR showed that both alleles may be expressed. Presence of immunoglobulin gene polymorphism appears to reflect the unusually high levels of intraspecies heterogeneity already demonstrated for major histocompatibility complex genes in this non-human primate species. [source] ORIGINAL ARTICLE: Epithelioid hemangioendothelioma in the right auricle of an adult, male Rhesus macaque (Macaca mulatta)JOURNAL OF MEDICAL PRIMATOLOGY, Issue 5 2010E.D. Lombardini Abstract Background, A 9-year-old, male castrate, Rhesus macaque was euthanized following a prolonged history of chronic renal failure. Results, Necropsy revealed a proliferative lesion within the right cardiac auricle composed of neoplastic epithelioid cells which infiltrated the myocardium and frequently exhibited intracytoplasmic luminae. Cells multifocally exhibited strong cytoplasmic immunoreactivity for Factor VIII-related protein (von Willebrand's factor). Conclusions, The histological characteristics of this tumor are consistent with a diagnosis of epithelioid hemangioendothelioma, an intermediate-grade vasoformative neoplasm which has to our knowledge not previously been reported in the heart of a non-human species. [source] Resident bacteria in a mixed population of rhesus macaque (Macaca mulatta) monkeys: a prevalence studyJOURNAL OF MEDICAL PRIMATOLOGY, Issue 6 2009C.A. Carrier Abstract Background, Microflora populations residing in oropharyngeal and gastrointestinal sites defend against pathogenic bacterial colonization. Perturbations in these microbial communities may allow opportunistic pathogenic bacteria to establish themselves and cause morbidity and mortality from sepsis particularly after stressful experimental procedures. This study determined the prevalent facultative bacteria in a resident population of Macaca mulatta prior to use in experimentally induced immunosuppressive radiation studies. Methods, Standard microbiological methods were used to assess prevalent facultative bacteria in the oropharynx and rectum of 24 male M. mulatta. Results, The majority of the bacteria isolated from the oropharyngeal and rectal sites were gram-positive cocci. Species of Staphylococcus and Streptococcus predominated in all samples. Few gram-negative bacteria were isolated. Conclusions, Bacteriological assessment is recommended to identify predominant bacterial species to be prepared to provide appropriate antimicrobial therapy in non-human primates that are expected to undergo stressful immunocompromising procedures. [source] Evaluation of the use of coconut to treat chronic diarrhea in rhesus macaques (Macaca mulatta)JOURNAL OF MEDICAL PRIMATOLOGY, Issue 6 2008J.L. Wilk Abstract Background, Chronic diarrhea can be challenging to manage in captive rhesus macaques (Macaca mulatta) leading to ongoing diagnostics, medications, monitoring, and potential euthanasia. Coconut has been used as a dietary supplement for people with inflammatory bowel disease, with anecdotal reports of decreased diarrhea following the dietary addition. A dietary trial in rhesus macaques was initiated to evaluate the hypothesis that dietary coconut decreases symptoms of chronic diarrhea in rhesus macaques. Methods, Ten rhesus macaques with chronic diarrhea were selected for the trial. Five of the subjects were fed coconut macaroons and five of the subjects were fed a sham cookie. Stool consistency was monitored daily for both groups. Results and conclusions, Data of chi-squared analysis obtained from eight rhesus macaques with chronic diarrhea showed that the use of coconut macaroons as a dietary supplement did not have a statistically significant effect on their diarrhea. [source] The efficacy of orally dosed ketamine and ketamine/medetomidine compared with intramuscular ketamine in rhesus macaques (Macaca mulatta) and the effects of dosing route on haematological stress markersJOURNAL OF MEDICAL PRIMATOLOGY, Issue 3 2008Andrew N Winterborn Abstract Background, This study compared the efficacy of two orally-dosed (PO) anaesthetic regimens for chemical immobilization in rhesus macaques (Macaca mulatta), versus the standard protocol of intramuscular (TM) ketamine. In addition, the effects of dosing route on haematological stress markers were evaluated. Methods, Testing was conducted on 18 chronically housed animals. Animals were trained to accept oral dosing and then randomly assigned to one of three drug regimens: (1) ketamine IM, (2) ketamine PO, (3) Ketamine/medetomidine PO. Sedation levels for each regimen were evaluated. Results, Oral dosing alone was not sufficient to achieve a plane of sedation that allowed for safe handling. Serum cortisol and glucose levels were unchanged across groups, although differences were observed in the leukogram profiles. Conclusion, The oral dosages used in this study fell short in providing adequate sedation for safe handling for routine veterinary procedures. Leukogram profiles indicated that orally dosed animals experienced a higher level of stress. [source] Establishing a standardized dental record-keeping system for a small investigational colony of rhesus monkeys (Macaca mulatta)JOURNAL OF MEDICAL PRIMATOLOGY, Issue 2008B.W. Gibson Abstract Background, Dental hygiene is becoming an increasingly important component of quality health care for laboratory animals, especially non-human primates (NHPs). One key to a successful health care program is an effective and efficient record-keeping system. Methods, To standardize a dental hygiene program for a small colony of NHPs, we developed a dental recording chart specific for rhesus monkeys. This dental chart was developed using the modified Triadan system. This system numbers teeth across species according to location. Results, An illustrative case report was presented to demonstrate the accurate record keeping and spatial relationship generated from this Old World NHP dental chart design. Conclusion, The development and implementation of a standardized dental chart, as part of a dental hygiene program will help minimize variables that may affect research data. [source] Alopecia areata in a rhesus monkey (Macaca mulatta)JOURNAL OF MEDICAL PRIMATOLOGY, Issue 3 2007B. Beardi Abstract Background, A 14-year-old female rhesus monkey (Macaca mulatta) of Chinese origin has been suffering from alopecia universalis since childhood. Methods, Recently, the health status of the animal was recorded comprehensively by detailed clinical examination including hematology and serology supplemented by histological and immunohistochemical investigations of skin biopsies and molecular biological techniques to clarify the causes of the persistent hair loss. Results and conclusions, The hairless gene (hr) nonsense mutation was ruled out by polymerase chain reaction and by sequencing of the corresponding gene. Histological examinations revealed a prominent chronic lymphocytic perifolliculitis and folliculitis affecting anagen stage hair follicles as well as miniaturized hair follicles. Immunohistochemistry using the antibodies CD3, CD20 and CD4 confirmed the diagnosis of a T-cell-mediated autoimmune disease resembling alopecia areata universalis in humans. [source] Coat condition, housing condition and measurement of faecal cortisol metabolites , a non-invasive study about alopecia in captive rhesus macaques (Macaca mulatta)JOURNAL OF MEDICAL PRIMATOLOGY, Issue 1 2006Hanspeter W. Steinmetz Abstract Background, Previous studies have characterized alopecia in captive rhesus macaques (Macaca mulatta) by a mixed partial to complete alopecia in a bilateral symmetric pattern. Methods, In this study, coat condition assessments were related to exogenous and endogenous factors in captive rhesus macaques under different housing conditions in order to identify disturbances in environmental factors controlling or influencing hair growth. Additionally, the degree of alopecia was investigated in relation to adrenal endocrine function as an indicator of social stress using faecal glucocorticoid measurements. Results, Hair loss was found to vary with season and sex, was most pronounced in adult females during the winter and spring months. Generally, infants were not affected, but alopecia developed during adolescence. However, the housing system, available enclosure space and variations in group size and composition also appeared to influence coat condition. Levels of immunoreactive cortisol metabolites (11-oxoetiocholanolone) in faeces were significantly negatively correlated with alopecia, suggesting a relationship between hypothalamic-pituitary-adrenal (HPA) axis activity and hair loss in captive rhesus macaques. Conclusions, Although the present study demonstrates the influence of the HPA axis on coat condition, it is not known if hair loss is caused by abnormal behaviour or hormonal imbalances of the HPA axis itself. Our data suggest that alopecia in rhesus macaques is a highly complex multicausal disorder. [source] Assessment of nutritional status in rhesus monkeys: comparison of dual-energy X-ray absorptiometry and stable isotope dilutionJOURNAL OF MEDICAL PRIMATOLOGY, Issue 3 2005Stéphane Blanc Abstract:, Body composition estimates from dual-energy X-ray absorptiometry and stable isotope dilution (2H and 18O) were compared in 61 rhesus monkeys (Macaca mulatta) from the ongoing long-term energy restriction study at the University of Wisconsin. Their average age was 18.9 ± 2.5 y/o. Of the animals, 51% were in the energy restricted group and 38% were females. Although the correlation between methods was highly significant for fat mass (R2 = 0.97, SEE = 0.25 kg or 7.5%, P < 0.0001) and fat-free mass (R2 = 0.98, SEE = 0.29 kg or 3.6%, P < 0.0001), we observed that dual-energy X-ray absorptiometry underestimated fat mass by 0.67 ± 0.26 kg (7.5%, P < 0.0001) and overestimated fat-free mass by 0.57 ± 0.29 kg (20%, P < 0.0001) when compared with isotope dilution. Taken together with data from the literature, the present results emphasize the usefulness of dual-energy X-ray absorptiometry to derive body composition and thus nutritional status in monkeys, but demonstrate the importance of validation experiments for a given DXA model and software. [source] Herpes B-virus seroreactivity in a colony of Macaca mulatta: data from the Sabana Seca Field Station, a new Specific Pathogen-Free ProgramJOURNAL OF MEDICAL PRIMATOLOGY, Issue 1 2005Carlos A. Sariol Abstract:, The demand for B-virus-free animals for biomedical research is increasing, while at the same time the availability of such animals is decreasing. The establishment of Specific Pathogen-Free (SPF) breeding macaque colonies is a priority of the National Institutes of Health. Nevertheless, it is well known that seroreactivity to B-virus can be difficult to interpret, particularly as it can vary over time in a single animal. The aim of the present study was to implement a reliable algorithm to examine B-virus reactivity among the rhesus monkey population of the Caribbean Primate Research Center. The sensitivity and specificity of our assay were determined using reports from two different laboratories as references. Whereas 95.4% of animals showed consistent serological status and 4.6% of animals recruited to this SPF program showed serovariability to B-virus over the initial 2 years of examination. Implications for all SPF programs are discussed in this article. [source] Fetal gender determination in early first trimester pregnancies of rhesus monkeys (Macaca mulatta) by fluorescent PCR analysis of maternal serumJOURNAL OF MEDICAL PRIMATOLOGY, Issue 6 2003Daniel F. Jimenez Abstract:, Non-human primate fetal gender determination can be a powerful tool for research study design and colony management purposes. The recent discovery of the presence of fetal DNA in maternal serum has offered a new non-invasive approach for identification of fetal gender. We present a rapid and simple method for the sexing of developing rhesus monkeys in the first trimester by polymerase chain reaction (PCR) analysis of maternal serum. Serum samples were obtained from 72 gravid rhesus monkeys during 20,32 days of gestation (term 165 ± 10 days). Fetal gender and the quantity of circulating fetal DNA were determined by real-time PCR analysis of the rhesus Y-chromosomal DNA sequences. The sensitivity for identifying a male fetus was 100% by 30 days gestation, and no false-positive results were observed. This study demonstrates that fetal gender can be reliably determined in the early first trimester from maternal serum samples, a non-invasive method for routine gender screening. [source] Mother-to-infant transmission of SIV via breast-feeding in rhesus macaquesJOURNAL OF MEDICAL PRIMATOLOGY, Issue 4-5 2003A.M. Amedee Abstract: To decipher the mechanisms involved in oral transmission of human immunodeficiency virus/simian immunodeficiency virus (HIV/SIV) through breast-feeding, we have developed an animal model using SIV-infected lactating rhesus macaques (Macaca mulatta) and their infants. Five of eight macaque infants became infected during a 10-month study course after SIV inoculation of lactating dams. In a second study, three of four chronically infected female macaques transmitted virus to their infants through breast-feeding within 4 months of birth. Transmission of virus to infants did not correlate with viral loads in either milk or plasma. Infants were infected with homogeneous virus populations, while milk samples near the time of transmission were more diverse. These studies suggest that specific viral phenotypes are selectively transmitted through breast-feeding. [source] Quantitative evaluation of Enterocytozoon bieneusi infection in simian immunodeficiency virus-infected rhesus monkeysJOURNAL OF MEDICAL PRIMATOLOGY, Issue 2 2003K. Sestak Abstract: The association of the microsporidia Enterocytozoon bieneusi with chronic diarrhea and wasting in individuals with acquired immunodeficiency syndrome (AIDS) has been demonstrated. The disease caused by E. bieneusi has been linked to decreased levels of circulating CD4+ T lymphocytes. In this study, we investigated the relationship between the extent of excretion of E. bieneusi in feces of simian immunodeficiency virus (SIV)-infected juvenile macaques and the CD4+ T lymphocyte counts in the peripheral blood. Twelve juvenile rhesus monkeys (Macaca mulatta) were intravenously inoculated with the pathogenic molecular clone SIVmac239. Numbers of CD4+ T lymphocytes were assessed by three-color flow cytometry. The presence of E. bieneusi DNA in feces was assessed by nested PCR. In addition, selected samples of feces were examined by competitive quantitative PCR to assess the level of E. bieneusi infection. Low (n = 5) to undetectable (n = 7) quantities of E. bieneusi were present in feces of the twelve animals in prior to inoculation with SIV. After SIV inoculation the number of animals shedding E. bieneusi increased (n = 10) as did the quantity of E. bieneusi shedding in the feces. Of the twelve juvenile animals, five animals died within 8 months post-SIV inoculation with symptoms of AIDS. Four of the five deceased animals showed shedding of E. bieneusi DNA in feces (,100 spores/g) for at least three consecutive months. Increased number of E. bieneusi in feces was accompanied by decreased counts of circulating CD4+ T lymphocytes and increased SIV plasma viral load. [source] Clinical and histopathological evaluation of 13 cases of adenocarcinoma in aged rhesus macaques (Macaca mulatta)JOURNAL OF MEDICAL PRIMATOLOGY, Issue 2 2002N.A. Rodriguez In recent years, the emphasis on aging research, has led to an increase in the number of aged macaques being maintained in some research facilities with a subsequent increase in the occurrence of age-related diseases. One of the most commonly reported age related diseases is intestinal adenocarcinoma. At the University of Illinois at Chicago (UIC), which maintains a colony of approximately 55 aged rhesus macaques 13 cases of intestinal adenocarcinoma were diagnosed within a 25-month period. This report provides a comprehensive description of the clinical findings for intestinal adenocarcinoma in aged rhesus macaques, including results from physical examinations, laboratory tests, radiographic evaluations, gross and histopathologic findings as well as a comparison with the disease condition in humans. The use of carcinoembryonic antigen as a potential tumor marker was evaluated by immunohistochemical analysis of tissue specimens in 10 cases. Intestinal adenocarcinoma is a disease condition that should be of concern to individuals responsible for the care of aged rhesus macaques. [source] Polymorphism in the Rhesus macaque (Macaca mulatta) NRAMP1 gene: lack of an allelic association to tuberculosis susceptibilityJOURNAL OF MEDICAL PRIMATOLOGY, Issue 1 2002Amos S. Deinard Although previous tuberculosis (TB) research has suggested that underlying genetic factors influence a host's response and ability to survive Mycobacterium infection, only recently has a gene been identified, the `natural resistance-associated macrophage protein 1' (NRAMP1) gene, which provides a degree of natural resistance to infection by some Mycobacterium species. To date, however, the role that NRAMP1 may play in resistance to Mycobacterium infection has only been examined in mouse and man. Here, we present data generated at NRAMP1 among a group of rhesus macaques (Macaca mulatta) that were euthanized because of an outbreak of Mycobacterium tuberculosis during quarantine. Data were also generated on unrelated (and healthy) rhesus macaques in order to better determine the frequency and degree of genetic polymorphism within Macaca at the NRAMP1 locus. These data represent the first study designed to examine the role that NRAMP1 may play in TB susceptibility among rhesus macaques. [source] Molecular cloning of three nonhuman primate follicle stimulating hormone ,-subunit cDNAsJOURNAL OF MEDICAL PRIMATOLOGY, Issue 6 2001M.J. Wolfgang The follicle stimulating hormone (FSH) ,-subunit cDNAs were cloned and sequenced for an old world primate, the rhesus monkey (Macaca mulatta), and two New World primates, the common marmoset (Callithrix jacchus) and pygmy marmoset (Cebuella pygmaea). The cDNA and predicted amino acid sequences of the rhesus monkey FSH ,-subunit were related most closely to the human FSH , -subunit (>96% identity). The common and pygmy marmosets have identical FSH , -subunit cDNAs, whereas the marmoset FSH , -subunit diverges from the rhesus and human molecules with less than 93% identity. These results have significance for the implementation of assisted reproductive technologies in the nonhuman primate as well as the evolution of genes encoding reproductive hormones. [source] Recombinant human gonadotropins for macaque superovulation: Repeated stimulations and post-treatment pregnanciesJOURNAL OF MEDICAL PRIMATOLOGY, Issue 6 2001C.A. VandeVoort This report summarizes data from the superovulation and ultrasound-guided follicular aspiration of 40 female rhesus monkeys (Macaca mulatta) with recombinant human gonadotropins. Of the animals treated, 12 were stimulated for only one cycle, either because of a poor response to the hormones or due to ectopic ovarian position precluding ease of access via ultrasound. The majority of animals were stimulated for a minimum of 3 cycles and 3 females continued to respond for a minimum of 8 and a maximum of 10 cycles. For those animals with repeated stimulation cycles, the number of follicles developed during each of the stimulation protocols remained relatively comparable. Of the animals mated since cessation of treatment, 70% conceived. There was no difference between the conception rate in this subset of animals and the rest of the macaque breeding colony. These data indicate that participation in these studies does not impact on the reproductive potential of female rhesus monkeys. [source] | |||||||||||||||||||