Showing papers on "Primate published in 1987"

The genetic consequences of primate social organization: a review of macaques, baboons and vervet monkeys

Abstract: Primates, as long-lived, iteroparous, socially complex mammals, offer the opportunity to assess the effects of behavior and demography on genetic structure Because it is difficult to obtain tissue samples from wild primate populations, research in this area has largely been confined to terrestrial and semi-terrestrial old world monkeys (eg, rhesus and Japanese macaques, vervets and several subspecies of baboons) However, these species display a multi-male, multi-female social structure commonly found in many other primate and non-primate mammals Electrophoretic analyses of blood proteins from individually recognized and/or marked wild Himalayan rhesus monkeys, themselves the subject of long-term behavioral and demographic research, have begun to reveal the genetic consequences of such phenomena as social group fission, malelimited dispersion, non-consanguineous mating patterns, and agonistically defined male dominance Specifically, rhesus social groups, consisting primarily of clusters of maternal relatives, appear to be nonrandom samples of a population's genotypes and genes The genetic effects of social group fission are highly dependent on each group's size, demographic structure, and average degree of relatedness In all cases fission contributes to the degree of intergroup genetic differentiation Male-limited dispersion appears both to retard genetic differentiation between social groups and to lead to mating patterns that result in an avoidance of consanguinity Groups, therefore, appear to be genetically outbred Comparing these results with studies of other free-ranging or wild cercopithecines allows several generalizations: (a) genetic variation seems to be evenly distributed throughout each local population of multi-male social groups; (b) social groups, however, because they contain clusters of relatives, are distinctive in their specific frequencies of genes; (c) the degree of genetic differentiation between a population's social groups, because of the effects of social group fission and non-deterministic forms of male dispersal, is somewhat greater than expected on the basis of migration rates alone; and (d) the asymmetrical pattern of dispersion with respect to sex effectively precludes inbreeding in any one social group or the population as a whole These observations have important implications for understanding the unusually rapid rates of evolution among the primates

Baculum length and copulatory behavior in primates.

Abstract: The length of the baculum (os penis) was measured in 74 adult males representing 46 primate species. These data, and a review of previously published measurements, indicate that variation in baculum length among primates is related to taxonomic and behavioral differences. Thus, many New World monkeys have shorter bacula, relative to body weight, than Old World monkeys. The baculum is shorter in colobine monkeys than in cercopithecines. Among the great apes, reduction of the baculum is more pronounced in Pan and Gorilla than in Pongo. Very long bacula are found in some nocturnal prosimians (eg, Lorisidae) and also in Macaca arctoides. A comparison of baculum length relative to body weight was made in 34 species for which detailed information on copulatory behavi or was available. The presence of an elongated baculum was shown to correlate with copulatory patterns involving prolonged intromission and/or the maintenance of intromission during the postejaculatory interval (eg, Galago crassicaudatus, Loris tardigradus, M, arctoides). The evolutionary significance of these observations is discussed and it is suggeted that similar copulatory patterns may occur in species with elongated bacula (eg, Daubentonia, Perodicticus) for which behavioral data are lacking at present. The same hypothesis also applies to an extinct adapid primate which possessed a very large baculum.

Natural History of Endemic Type D Retrovirus Infection and Acquired Immune Deficiency Syndrome in Group-Housed Rhesus Monkeys

Abstract: A 2.5-year epidemiologic study of a breeding group of rhesus monkeys (Macaca mulatta), which is a focus of endemic simian acquired immunodeficiency syndrome (SAIDS), demonstrated a strong association between the occurrence of SAIDS and infection with a type D retrovirus, SAIDS retrovirus serotype 1 (SRV-1). Of 23 healthy "tracer" juvenile rhesus monkeys, 19 (83%) died with SAIDS within 9 months of introduction into the resident SAIDS-endemic population. In contrast, 21 healthy "sentinel" juvenile rhesus monkeys placed in the same outdoor enclosure but denied physical contact with the SAIDS-affected group by a 10-foot-wide "buffer zone" remained free of SRV-1, SRV-1 antibody, and disease for 2.5 years. The SAIDS-specific mortality rate was significantly higher in juveniles than in adults. In repeated serologic testing, the overall prevalence of SRV-1 antibody ranged from 68 to 85%. Antibody prevalence increased with age. Seroconversion was found to be a poor indicator of infection rate, as approximately 50% of virus-positive juvenile monkeys had no antibody detectable by enzyme-linked immunosorbent assay. Repeated viral isolations from all animals revealed 1) SRV-1 viremia with clinical SAIDS; 2) persistent viremia and viral shedding in apparently healthy animals; 3) transient viremia and clinical recovery; 4) intermittent viremia, suggesting activation of latent infections; and 5) viremia in a 1-day-old infant, suggesting transplacental transmission. The prevalence of SRV-1 antibody in SAIDS-free breeding groups of rhesus monkeys was 4%. The seroprevalence of antibodies against human T-cell leukemia virus type 1 (HTLV-1), human immunodeficiency virus (HIV), and simian immunodeficiency virus (SIV; formerly STLV-III) was uniformly low or absent in both SAIDS-free and SAIDS-affected groups of rhesus monkeys, demonstrating that these retroviruses are not etiologically linked to SAIDS at the California Primate Research Center.

Anatomical demonstration of ocular segregation in the retinogeniculocortical pathway of the New World capuchin monkey (Cebus apella).

Abstract: We describe the architecture of the dorsal lateral geniculate nucleus and primary visual cortex (striate cortex; area 17) of the New World capuchin monkey (Cebus apella) on the basis of the distribution of cell bodies and cytochrome oxidase histochemistry. Changes in staining for cytochrome oxidase following unilateral enucleation served to indicate the organization of the representation of the two eyes in the retinogeniculocortical pathway. The number and disposition of eye-specific layers within the lateral geniculate nucleus of Cebus are consistent with the common plan of geniculate organization in anthropoid primates, and the radial organization of area 17 fits the pattern common to New World squirrel and Old World macaque monkeys, including the presence of cytochrome-oxidase-rich zones in supragranular and deeper cortical layers (Horton: Philos. Trans. R. Soc. Lond. [Biol.]304: 199–253, '84). Our principal finding is that cytochrome oxidase histochemistry following unilateral eye removal unequivocally reveals ocular dominance columns in the striate cortex of Cebus. As in the macaque (Hubel: Nature 292: 762–764, '82), ocular dominance columns extend through the thickness of cortex and blobs are centered on columns, but the array of columns viewed tangentially is less orderly or more mosaic than in the macaque, and there is apparently significant overlap between columns. The presence of well-defined ocular dominance columns in Cebus, as in Ateles (Florence, Conley, and Casagrande: J. Comp. Neurol. 243: 234–248, '86) but not in other New World monkeys examined previously, emphasizes the phylogenetic lability of binocular segregation in the primate visual cortex. In addition, the present results indicate significant differences with respect to the tangential organization of the ocular dominance domain between primate species in which ocular dominance columns are present.

Primate involucrins: antigenic relatedness and detection of multiple forms.

Abstract: Hominoid apes (gorilla, chimpanzee, orangutan, gibbon), Old World monkeys (rhesus, cynomolgus), New World monkeys (owl, cebus), and a prosimian (lemur) express involucrin-like proteins in cultured keratinocytes. Primate involucrins can be precipitated with trichloroacetic acid, resolubilized at pH 8, and subsequently retain aqueous solubility in 67% ethanol. Polyacrylamide gel electrophoresis of keratinocyte extracts after this rapid partial purification has revealed in each species tested one (chimpanzee, orangutan, gibbon) or two (gorilla, rhesus, owl, cebus) antigenically crossreactive proteins that migrate in the vicinity of human involucrin. In the species examined further (gorilla, chimpanzee, rhesus), poly(A)+ mRNA isolated from the cultures directed the cell-free translation of polypeptides with mobilities similar to those extracted from the cells. From five cynomolgus monkeys, three different electrophoretic profiles were obtained, suggesting the existence of different alleles. Quantitative comparisons by a sensitive enzyme-linked immunosorbent assay indicated that certain primate involucrins have a higher density of antigenic determinants than the human protein, whereas others lack some determinant(s). In contrast to those from other species, all of which showed substantial crossreactivity, the lemur protein was minimally immunoreactive by immunoblotting and not clearly detected by solid-phase assay. The electrophoretic and antigenic differences displayed throughout the primate order suggest that this protein has been subject to relatively rapid evolution.

Auditory duration discrimination in Old World monkeys (Macaca, Cercopithecus) and humans

Abstract: Auditory duration DLs at 2.0 kHz were measured in Old World monkeys (Macaca, Cercopithecus) and humans using a go, no‐go repeating standard AX procedure and positive reinforcement operant conditioning techniques. For a 200‐ms standard, monkey DLs were 45–125 ms, compared to 15–27 ms for humans. Weber fractions (ΔT/T) for all species were smallest at standard durations of 200–400 ms and increased as standard duration decreased to 25 ms. Varying intensity from 30–70 dB SPL had only minor effects on DLs, except at the lowest levels tested, where DLs were elevated slightly. Monkeys had difficulty discriminating duration decrements, in contrast to humans. Results are discussed in relation to other comparative psychoacoustic data and primate vocal communication, including human speech.

Survey of nonhuman primates for antibodies reactive with Epstein-Barr virus (EBV) antigens and susceptibility of their lymphocytes for immortalization with EBV.

Abstract: The susceptibility to transformation with Epstein-Barr virus (EBV) and the prevalence of antibodies reactive to EBV were examined in 43 primate species. In vitro EBV infection was revealed in lymphocytes from Old World monkeys, including patas monkeys and the colobines, as well as in lymphocytes from the apes. Antibodies reactive to EBV-early antigen/viral capsid antigen (EA/VCA) were detected in all the species of Old World monkeys and apes examined and in two out of seven species of New World monkeys.

Interhemispheric connections in the visual cortex of the squirrel monkey (Saimiri sciureus).

Abstract: The callosal connections within the posterior parietal and occipital cortices were studied in the squirrel monkey with horseradish peroxidase tracing techniques. The data were evaluated with particular emphasis on the relationship of major callosal connections along the 17-18 border. The overall pattern of callosal connections in the squirrel monkey also was compared with callosal patterns in other New World simians. Our results show that the dense band of callosal connections along the 17-18 border in the squirrel monkey differs from the connections observed in other New World monkeys in that it is virtually confined to area 18 and avoids area 17. In addition to a continuous band of callosal connections in area 18 that parallels the 17-18 border, rostral extensions of the band are oriented perpendicular to the 17-18 border and present an obvious periodicity. The remaining parieto-occipital cortex contains a complex pattern of callosal connections that is strikingly similar to patterns reported for other New World monkeys. Thus, it is likely that the dorsolateral extrastriate visual cortex in the squirrel monkey is organized in a manner similar to that found within other New World monkeys.

Social responses to the traumatic injury of a juvenile spider monkey (Ateles geoffroyi)

Abstract: The behavioural development of a juvenile male spider monkey (Ateles geoffroyi) preceding and subsequent to a traumatic injury resulting in the loss of his tail, was documented over a nine-month period in Santa Rosa National Park, Costa Rica. The juvenile became heavily reliant on his mother, who readily provided compensatory care, including nursing the juvenile even though he had previously been weaned. In comparison to another juvenile male spider monkey of similar age, the development of the injured animal was severely retarded and even five months after the accident, the juvenile was still nursing and being carried by his mother. As injuries may be relatively common among primates it is suggested that the provision of compensatory care is an important trait in many primate species.

Disseminated cryptosporidiosis in simian immunodeficiency virus/delta-infected rhesus monkeys.

Abstract: Cryptosporidiosis has recently been recognized as a significant primary pathogen in animals and humans.s With emergence of acquired immunodeficiency syndrome (AIDS) in humans, there have been several reports of persistent diarrhea, fever, abdominal pain, and weight loss associated with Cryptosporidium infections, usually resulting in death.2.4.9 As of April 1986, 697 of the 19,182 reported AIDS patients (3.6%) had confirmed cases of cryptosporidiosis.8 Reports of cryptosporidiosis outbreaks in day-care centers and as the cause of traveler's diarrhea have increased awareness of this agent as the cause of disease in immunocompetent people as Recent studies on the development of an animal model for AIDS, using rhesus monkeys infected with Simian Immunodeficiency Virus (SIV), have been very promising. 1.7 Initial studies indicate that there are many similarities between SIV and the human AIDS virus, with parallel effects on the immune system of the host and similar opportunistic infections. Cryptosporidiosis has been reported in the gallbladder, biliary and pancreatic ducts, and intestine of macaques, prior to the discovery of SIV.3,6~10 All of the affected monkeys were infants or juveniles and had evidence of thymic atrophy, common in severely ill macaques (Blanchard and Baskin, personal observation), pneumonia, or gastrointestinal disease. We report here findings of four cases of cryptosporidiosis involving multiple organs (including the respiratory tract) in young rhesus monkeys experimentally infected with SIV/Delta at the Delta Regional Primate Research Center. The four affected rhesus monkeys were inoculated (at 7 to 15 months of age) with SIV/Delta, a retrovirus originating from a mangabey monkey. These animals were part ofa series of inoculation experiments in which 34 monkeys received SIV from various sources, including tissue from an asymptomatic mangabey monkey, lymphoid cells from a rhesus monkey with lymphoma, cultured virus pooled from several infected rhesus monkeys, and tissue culture derived virus isolated from a single rhesus monkey. Twenty-three of the 34 SIV-inoculated monkeys have died, 19 with opportunistic infections or lymphoma characteristic of the SIV-induced acquired immunodeficiency. Four of the 19 monkeys were diagnosed as having cryptosporidiosis after microscopic examination of tissue sections. The four Cryptosporidium-infected monkeys were necropsied immediately following euthanasia with an overdose of sodium pentobarbitol. Samples of all major organs were fixed in neutral buffered formalin and sectioned at 4-6 pm. Three random samples of small intestine (one each at the duodenum, the jejunum, and terminal ileum) and two samples of large bowel (one at the apex of the cecum and one at the mid-colon) were examined. Lesions were considered mild if cryptosporidial organisms were few in number and/or only a few inflammatory cells were seen. Changes were severe if numerous organisms (20 or more per villus) were present, if there was sloughing of the mucosa, and if 30 or more inflammatory cells per high power field were present. All four Cryptosporidium-infected monkeys died within 5 to 7 months after SIV inoculation with persistent or recurrent diarrhea and a combination of five or more of the following conditions: wasting, lymphoid atrophy, thymic atrophy, hepatitis, encephalitis, amyloidosis, bone marrow hyperplasia, glomerulosclersis, syncytial cell formation, and disseminated intravascular coagulation. Infectious agents included cytomegalovirus, adenovirus, Campylobacter, Cryptosporidium, Strongyloides, Candida, and Pneumocystis. All four monkeys died of a combination of several infectious agents, but cytomegalovirus, adenovirus, and cryptosporidiosis were the most severe. Two of the four monkeys had disseminated cryptosporidiosis involving the trachea, bronchioles, bile ducts, gallbladder, pancreatic ducts, and small intestine. Two other animals had small intestinal cryptosporidial infections ranging from mild to moderate that were segmental (present in some sections but not in others). Gastric and colonic mucosa were not involved in any of the four monkeys based on examination of one section of stomach and two sections of large bowel. Small intestinal changes were severe multifocal villus atrophy with synechia and moderate subacute inflammation of the lamina propria. The mucosal epithelium was flattened, especially in areas with high numbers of Cryptosporidiurn (20 or more per villus). The various stages of the organism were 4 to 7 pm in diameter, round to oval, and stained dark basophilic with pale centers. Organisms were primarily found on the mucosal surface, with occasional infected crypts in severely affected sections of small intestine. The associated mucosa had diffise moderate degeneration of epithelial cells with flattening and focal sloughing (Fig. 1). The lamina propria contained a moderate infiltration of plasma cells, lymphocytes, and macrophages. In addition, tips of villi had focal accumulations of pyknotic and vacuolated macrophages. A moderate number of crypts were infected with cryptosporidia and had a few sloughed cells and cell debris. A few crypts were hyperplastic and had several mitotic figures. Other changes associated with infectious agents, in addition to cryptosporidia, included lysis of cells due to cytomegalovirus and

Aspects of fight interference in free‐ranging and compound‐dwelling rhesus macaques (Macaca mulatta)

Abstract: Patterns of fight interference (agonistic aiding) were compared among three groups of rhesus monkeys (Macaca mulatta) living in two settings: (1) two groups at Cayo Santiago (Caribbean Primate Center); and (2) one group at the Yerkes Regional Primate Research Center (YRPRC). A total of 1,227 interference episodes were recorded in 1,650 hours of observation. The only significant intergroup difference was the increased tendency of males at YRPRC to aid aggressors rather than victims. Among other findings, females aided relatives, interfered against target animals dominant to themselves, aided juveniles, and aided victims more consistently and frequently than did males. Importantly, female interference became more male-like in pattern when aid was given to nonrelatives. Neither the dominant males nor males in general displayed a unique or consistent tendency to interfere in fights in a manner which could be interpreted as controlling aggression. The males' interference patterns also did not suggest they were forming coalitions to either attain or defend status rankings. It is concluded that, overall, observations of compound-dwelling and free-ranging rhesus monkeys reveal similar relationships. Further, while female rhesus monkeys interfered in fights in a manner consistent with the control of aggression and protection of kin, the motives of male interferers remain unknown; however, their behavior is consistent with the hypothesis that they were reducing intermale tensions while, at the same time, minimizing physical risk.

Primate research: relevance to human learning and development.

Abstract: The monkey has proved an extremely useful model with which to examine the effects of developmental exposure to neurotoxic agents such as lead. Like humans, monkeys have a long period of gestation, infancy and sexual immaturity during which they continue to develop. This long period of vulnerability allows investigation of critical variables concerning sensitive periods of exposure. The nervous system of the monkey is very similar to humans and often responds to toxic insult like the human system. The behavioral repertoire of the monkey is also more like the human than is that of other laboratory species. Monkeys were exposed from birth with doses of lead that resulted in blood lead concentrations observed routinely in the population of children, and which are presently considered safe. Behavioral impairment was observed consistently in those monkeys on measures of activity, attention and memory, distractibility, adaptability and learning ability. Impairment persisted into adulthood.

Isozymes as bioprobes for genetic analysis of nonhuman primates.

Abstract: The identification and the utilization of genetically determined electrophoretic differences of enzymes between the individuals of species as well as between cell lines have played an important role in the advancement of mammalian genetics during the past quarter of a century. In an explicit search we found a number of red cell enzyme polymorphisms in each of the following four species: chimpanzees, orang utans, rhesus monkeys and brown capuchins. Allelic distribution patterns among populations have indicated trends of subspeciation among chimpanzees and orang utans due to geographic barriers leading to reproductive isolation. Investigations of quantitative levels of red cell glucose-6-phosphate dehydrogenase have suggested that relative activity profiles of certain enzymes among species may be helpful in studies of the evolution of physiological traits and their biological significance during speciation. A large number of biochemical genetic markers in primate-rodent (i.e., chimpanzee-, gorilla-, orang utan-, rhesus monkey- and African green monkey-Chinese hamster) somatic cell hybrids have been identified and are useful for primate genetic analysis. Some of the biologically relevant observations on the enzyme markers in the above mentioned primate species are discussed.