Primate

About: Primate is a research topic. Over the lifetime, 1250 publications have been published within this topic receiving 67388 citations. The topic is also known as: the primate order & primates.

Encephalitozoonosis in Squirrel Monkeys (Saimiri sciureus)

Abstract: Twenty-two cases of naturally occurring encephalitozoonosis in squirrel monkeys are reported from breeding colonies of the Delta Regional Primate Research Center, Covington, La. Characteristic foci of granulomatous inflammation and organisms were demonstrated in brains, kidneys, lungs, adrenals, and livers. Vasculitis and perivasculitis were also common lesions in several organs. At least seven cases were congenital while ten others occurred in monkeys less than nine months old. Granulomatous placentitis, previously unreported in any species due to Encephalitozoon cuniculi, was present in one monkey.

The ontogeny of cranial sexual dimorphism in two old world monkeys: Macaca fascicularis (Cercopithecinae) and Nasalis larvatus (Colobinae)

Abstract: Allometric and heterochronic approaches to sexual dimorphism have contributed much to our understanding of the evolutionary morphology of the primate skull and dentition. To date, however, extensive studies of sexual dimorphism have been carried out only on the great apes and a few cercopithecine monkeys. To fill this gap, representative dimensions of the skull were collected among ontogenetic series of two dimorphic Old World monkeys:Macaca fascicularis (Cercopithecinae) andNasalis larvatus (Colobinae). The ontogeny of cranial sexual dimorphism was evaluated with least-squares bivariate regression, analysis of covariance (ANCOVA), and analysis of variance (ANOVA). Results indicate that within each species the sexes typically exhibit nonsignificant differences in ANCOVAs of ontogenetic trajectories, except for bivariate comparisons with bicanine breadth. AmongMacaca fascicularis, ANOVAs between males and females of common dental ages show that adult, and frequently subadult, males are significantly larger than females, i.e., sexual dimorphism develops via time and rate hypermorphosis (males primarily grow for a longer time period as well as faster). AmongNasalis larvatus, however, comparisons between males and females of common dental ages indicate that only adult males are significantly larger than females, i.e., sexual dimorphism develops primarily via time hypermorphosis (males grow for a longer time period). Within both species, females appear to exhibit an early growth spurt at dental age 2; that is, many cranial measures for females tend to be larger than those for males. Measures of the circumorbital region (e.g., browridge height), body weight, and bicanine breadth exhibit typically the highest sexual dimorphism ratios. The fact that postcanine toothrow length and neurocranial volume (less so inNasalis) demonstrate very low dimorphism ratios generally supports assertions that postnatal systemic growth (and associated selective pressures thereon) exerts a greater influence on facial, but not neural, dental, or orbital, development (Cochard, 1985, 1987; Shea, 1985a,b, 1986; Shea and Gomez, 1988; Sheaet al., 1990). Additional consideration of ontogenetic differences between species generally supports previous functional interpretations of subfamilial differences in cranial form related to agonistic displays in cercopithecine monkeys (Ravosa, 1990).

Mixed-species primate groups in the kibale forest: Ecological constraints on association

Abstract: Five species of diurnal primates in the Kibale Forest of western Uganda— red colobus (Colobus badius),black- and- white colobus (Colobus guereza),redtail monkeys (Cercopithecus ascanius),blue monkeys (Cercopithecus mitis),mangabeys (Cercocebus albigena)-often associate in mixed- species groups that vary in size and composition from day to day. Across this range of species, we found no consistent effect of association on feeding rate. In addition, there is no systematic difference between the species- specific individual feeding rates when animals were in mixed- species groups feeding in a specific tree on one day and when individuals of one of the same species were feeding in the same individual tree on a subsequent day. If associating in a mixed- species group lowers the risk of predation, one might expect that the number of vigilant events would decrease in mixed- species groups. However, the only species to exhibit a consistent decrease in vigilant behavior when in association was the red colobus. Redtail monkeys were more vigilant when in association. We predicted that the density and distribution of food resources would both constrain the frequency of association and the size of mixed- species groups. Based on 22 months of data on food resources and bimonthly censuses, we found no relationship between the frequency of association (except mangabeys) or mean mixed- species group size and the density and distribution of food resources for all species. Finally, we examined the behavior of the monkeys in and out of association before and after the playback of a crowned hawk eagle call (Spizaetus coronatus),a known predator. When more species were in association, the amount of time they spent being vigilant following the playback was greater and the response more intense than when fewer species were in association or when the group was alone. The results of this study illustrate that the nature of the costs and benefits of polyspecific associations for these different monkey species are complex and vary from species to species.

Simian T-Cell Leukemia Virus (STLV) Infection in Wild Primate Populations in Cameroon: Evidence for Dual STLV Type 1 and Type 3 Infection in Agile Mangabeys (Cercocebus agilis)

Abstract: Three types of human T-cell leukemia virus (HTLV)-simian T-cell leukemia virus (STLV) (collectively called primate T-cell leukemia viruses [PTLVs]) have been characterized, with evidence for zoonotic origin from primates for HTLV type 1 (HTLV-1) and HTLV-2 in Africa. To assess human exposure to STLVs in western Central Africa, we screened for STLV infection in primates hunted in the rain forests of Cameroon. Blood was obtained from 524 animals representing 18 different species. All the animals were wild caught between 1999 and 2002; 328 animals were sampled as bush meat and 196 were pets. Overall, 59 (11.2%) of the primates had antibodies cross-reacting with HTLV-1 and/or HTLV-2 antigens; HTLV-1 infection was confirmed in 37 animals, HTLV-2 infection was confirmed in 9, dual HTLV-1 and HTLV-2 infection was confirmed in 10, and results for 3 animals were indeterminate. Prevalences of infection were significantly lower in pets than in bush meat, 1.5 versus 17.0%, respectively. Discriminatory PCRs identified STLV-1, STLV-3, and STLV-1 and STLV-3 in HTLV-1-, HTLV-2-, and HTLV-1- and HTLV-2-cross-reactive samples, respectively. We identified for the first time STLV-1 sequences in mustached monkeys (Cercopithecus cephus), talapoins (Miopithecus ogouensis), and gorillas (Gorilla gorilla) and confirmed STLV-1 infection in mandrills, African green monkeys, agile mangabeys, and crested mona and greater spot-nosed monkeys. STLV-1 long terminal repeat (LTR) and env sequences revealed that the strains belonged to different PTLV-1 subtypes. A high prevalence of PTLV infection was observed among agile mangabeys (Cercocebus agilis); 89% of bush meat was infected with STLV. Cocirculation of STLV-1 and STLV-3 and STLV-1-STLV-3 coinfections were identified among the agile mangabeys. Phylogenetic analyses of partial LTR sequences indicated that the agile mangabey STLV-3 strains were more related to the STLV-3 CTO604 strain isolated from a red-capped mangabey (Cercocebus torquatus) from Cameroon than to the STLV-3 PH969 strain from an Eritrean baboon or the PPA-F3 strain from a baboon in Senegal. Our study documents for the first time that (i) a substantial proportion of wild-living monkeys in Cameroon is STLV infected, (ii) STLV-1 and STLV-3 cocirculate in the same primate species, (iii) coinfection with STLV-1 and STLV-3 occurs in agile mangabeys, and (iv) humans are exposed to different STLV-1 and STLV-3 subtypes through handling primates as bush meat.

Age-Associated Pathology in Rhesus Macaques (Macaca mulatta)

Abstract: The rhesus macaque (Macaca mulatta) is one of the most extensively used nonhuman primate models for human diseases. This article presents a literature review focusing on major organ systems and age-associated conditions in humans and primates, combined with information from the Wisconsin National Primate Research Center Electronic Health Record database to highlight and contrast age-associated lesions in geriatric rhesus macaques with younger cohorts. Rhesus macaques are excellent models for age-associated conditions, including diabetes, osteoarthritis, endometriosis, visual accommodation, hypertension, osteoporosis, and amyloidosis. Adenocarcinoma of the large intestine (ileocecocolic junction, cecum, and colon) is the most common spontaneous neoplasm in the rhesus macaque. A combination of cross-sectional and longitudinal studies is required to truly define mechanisms of maturation, aging, and the pathology of age-associated conditions in macaques and thus humans. The rhesus macaque is and will continue to be an appropriate and valuable model for investigation of the mechanisms and treatment of age-associated diseases.