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PubMed1993

Kong toys for laboratory primates: are they really an enrichment or just fomites?

Simple toys as enrichment devices have been associated with a rapid decline in their use by nonhuman primates. Other facets of toy presentation have not been described previously. For example, a comparison of the effect(s) of an enrichment device between two facilities should be validated if enrichment recommendations are to be made that affect diverse research facilities across the country. Additionally, a comparison of two methods of presentation (one highly accessible to the animal and the other less accessible) of the same enrichment device for potential differences in efficacy could provide direction in implementing an enrichment program based on simple toys. The handling of enrichment devices by nonhuman primates can lead to the spread of microbial contamination. The typical enrichment program rotates enrichment devices among animals to maximize the variety of stimuli available to each primate in the most economic manner. An adequate sanitation program is therefore pivotal to minimizing the potential for enrichment devices to be fomites. We conducted three experiments that addressed these issues. The results confirmed that, although the presence of a simple toy reduced behavioral pathology, there was variability in behavioral effect for an enrichment technique between facilities. Two methods of presentation (on floor and suspended) of a simple toy did not produce any significant differences in use. Finally, we demonstrated that microbial growth can persist on enrichment devices after they have been sanitized in a commercial cagewasher.

Animals↗
PubMed1996

Role of hypoestrogenism or sex steroid antagonism in adhesion formation after myometrial surgery in primates.

OBJECTIVE: To determine the contribution of estrogen in the development of pelvic adhesions during myometrial surgery. DESIGN: A randomized, prospective study in the nonhuman primate. SETTING: A primate colony, Department of Obstetrics and Gynecology, Eastern Virginia Medical School. INTERVENTIONS: All primates were assigned prospectively to one of three treatment groups: [1] GnRH analogue (GnRH-a), [2] mifepristone, or [3] vehicle control. After 3 months of treatment, a standard uterine fundal hysterotomy, for full thickness endometrial biopsy, was performed at the time of exploratory laparotomy, with subsequent scoring of utero-omental adhesions to the hysterotomy site at a future staging procedure based upon adhesion area, vascularity, and tenacity. Serum was drawn on the day of surgery for E2 determination. Endometrial height, from the surface interface between the endometrium and myometrium, was used as a bioassay of estrogen activity. RESULTS: The hypoestrogenic (GnRH-a) group and the mifepristone group had significantly fewer utero-omental adhesions compared with the normally cycling control monkeys as measured by a lower adhesion score. Similarly, the endometrial thickness was significantly reduced in the GnRH-a and mifepristone groups (one-third) compared with the cycling controls, demonstrating the effects of either hypoestrogenism or noncompetitive estrogen antagonism. Serum E2 on the day of surgery was predictive of the postoperative adhesion score by both a regression analysis and analysis of covariance. CONCLUSIONS: The actions of E2 seem to have a dramatic effect on the formation of pelvic adhesions after myometrial surgery.

Animals↗
PubMed1996

Enhancement of primate oocyte maturation and fertilization in vitro by inhibin A and activin A.

OBJECTIVE: A role for inhibin and activin in primate oocyte maturation was investigated. DESIGN: The maturation and fertilization of rhesus monkey oocytes recovered from the excised ovaries of nine regularly cycling animals was compared for untreated germinal vesicle (GV)-intact controls versus oocytes cultured in the presence of inhibin, activin, inhibin + activin, or in a combination with follistatin. SETTING: Nonhuman primates in a research institute environment. INTERVENTIONS: Bilateral oophorectomy. MAIN OUTCOME MEASURE: Oocyte maturation from germinal vesicle breakdown (GVBD) to metaphase II (MII) and fertilization. RESULTS: Germinal vesicle breakdown, progression to MII and fertilization was monitored in oocytes cultured for 48 hours. Activin alone, at an optimum concentration of 100 ng/mL, stimulated GVBD whereas both GVBD and MII development was enhanced in the presence of inhibin + activin. The latter also accelerated the rate of maturation to MII. All treatment groups exhibited a higher incidence of GVBD compared with controls. When follistatin was added, the stimulatory effect of activin or activin + inhibin was abolished. Exposure to medium containing inhibin + activin significantly increased the percentage of MII oocytes that fertilized compared with controls (68% versus 25%, respectively). CONCLUSIONS: Inhibin and activin are potent stimulators of primate oocyte maturation, producing mature oocytes in vitro that fertilize with high efficiency.

Activins↗
PubMed1997

The primate erythrocyte complement receptor (CR1) as a privileged site: binding of immunoglobulin G to erythrocyte CR1 does not target erythrocytes for phagocytosis.

The primate erythrocyte (E) complement receptor, CR1, is a transmembrane glycoprotein located in clusters on the surface of E. In vivo studies have demonstrated that during processing and clearance of complement-opsonized immune complexes, large amounts of immunoglobulin G (IgG) can be bound to primate E via CR1 with no E loss or lysis. However, when comparable amounts of IgG are bound to other sites on E, in many cases the E are cleared from the circulation by the mononuclear phagocytic system. Therefore, due to its role in immune complex processing, CR1 may represent a privileged site on the primate E. To delineate further this property of E CR1, we performed in vitro phagocytosis assays in the absence of complement and examined the ingestion of E, opsonized at various sites with IgG, by peripheral blood monocytes. When either human or rhesus monkey E were opsonized at sites other than CR1, with between 1,000 and 15,000 IgG per E, substantial phagocytosis of E was evident. However, when comparable amounts of IgG were bound exclusively via CR1, little, if any, phagocytosis was observed. The key to the low phagocytic level of E opsonized via CR1 may be related to the requirements of a "zipper mechanism" for phagocytosis first annunciated by Griffin et al. Based on their findings, we suggest that due to the presence of preexisting clusters of CR1 on the E membrane, large amounts of IgG can be bound to E under conditions that preclude circumferential engagement (and phagocytosis) of the entire E by Fc receptors on the monocyte.

Animals↗
PubMed1997

A nonhuman primate model of excessive alcohol intake. Personality and neurobiological parallels of type I- and type II-like alcoholism.

Developmental, biochemical, and behavioral concomitants of voluntary excessive alcohol consumption were investigated using a nonhuman primate model. Studies were designed to investigate potential neurobiological and behavioral parallels of Cloninger's subtypes of type I and type II alcoholism in nonhuman primates. The studies have shown that a subpopulation of primates chronically consume intoxicating amounts of alcohol. Subjects that chronically consume intoxicating amounts of alcohol often exhibit neurobiological and behavioral features that were predicted by Cloninger's model for subtypes of alcoholism among humans. Investigations showed that behavior patterns and biological indices that characterize high anxiety, whether constitutionally or stress induced, were correlated with high rates of alcohol consumption, consistent with predictions for type I alcoholism. Early untoward rearing experiences that increased anxiety increased the probability that subjects would chronically drink alcohol to intoxication. Investigations of type II-like alcohol consumption patterns focused on subjects with low central nervous system (CNS) serotonin functioning [as measured by reduced cerebrospinal fluid (CSF) concentrations of the serotonin metabolite 5-hydroxyindoleacetic acid (5-HIAA)]. CSF 5-HIAA in infancy was shown to be a relatively stable neurobiological trait across development into adulthood. An individual CSF 5-HIAA concentration in infancy was shown to be a consequence of paternal and maternal genetic influences. Early parental neglect reduced CSF 5-HIAA concentrations. Low CSF 5-HIAA and CNS norepinephrine functioning were shown to predict excessive alcohol consumption in adolescence. Behaviorally, subjects with low CSF 5-HIAA demonstrated impaired impulse control, which resulted in excessive and inappropriate aggression, infrequent and inept social behaviors, low social status, social isolation and expulsion from social groups at an early age, and high rates of early mortality. With some exceptions, these findings were consistent with predictions from Cloninger's type II model of excessive alcohol consumption among men who exhibit impaired impulse control and violent and antisocial behaviors.

Alcoholic Intoxication↗
PubMed1996

Histochemical characterization of NADPH-diaphorase activity in area 17 of diurnal and nocturnal primates and rodents.

NADPH-diaphorase (NADPH-d) activity was studied comparatively in area 17 of four mammalian species, two primates and two rodents. Three brain hemispheres each from adult capuchin-monkeys, owl-monkeys, agoutis and guinea pigs were fixed with aldehyde fixatives by perfusion and 200 microns sections were submitted to NADPH-d histochemistry, using the indirect malic enzyme method. In all species studied the neuropil pattern of enzymes activity presented a clear layered appearance. In primates, histochemical staining was most intense in layer IVc, while in rodents the highest intensity of the neuropil reaction was in supragranular layers (II and III). Comparison of cell density in grey and white matter showed that the majority of NADPH-d-positive neurones were located in the white matter of primates but not of rodents. Since NADPH-d is a nitric oxide synthase the results are very important for comparative functional studies of neuromediators and their correlations with laminar and modular organization of area 17 of the mammalian brain.

Animals↗
PubMed1997

Antibodies to VLA4 integrin mobilize long-term repopulating cells and augment cytokine-induced mobilization in primates and mice.

Although the use of cytokine-mobilized peripheral blood stem cells has gained a significant momentum in clinical transplantation, the mobilization schemes practiced are guided by a great deal of empiricism. The mechanism(s) by which cytokines or chemokines, alone or in combination, bring about redistribution of stem/progenitor cells from bone marrow to peripheral blood are poorly understood. Likewise the fate of mobilized stem/progenitor cells and their biological properties are incompletely defined. One of the leading hypotheses to explain the mechanism of cytokine-induced mobilization encompasses the view that cytokines disrupt, directly or indirectly, cytoadhesive interactions of stem/progenitor cells with their bone marrow stroma. Compatible with this view are changes in the expression and/or function of several cytoadhesion molecules, especially integrins, postmobilization, and extensive in vitro experimentation supporting the concept of cytokine/integrin interactions. To provide a further insight on the cytokine/integrin interplay in vivo, we have combined cytokine treatments with anti-integrin treatments for mobilization in primates and mice. We found that anti-VLA4 treatment combined with either granulocyte colony-stimulating factor (G-CSF ) treatment or kit ligand treatment leads to significant enhancement of mobilization efficiency (fivefold to eightfold) well above the levels produced by either cytokine alone or anti-VLA4 treatment alone. Similar enhancement was seen when combinations of cytokines, ie, G-CSF plus kit ligand or G-CSF plus Flt3-ligand were used with anti-VLA4 in primates and mice. Furthermore, when anti-VLA4 was given in 5-Fluorouracil-treated primates, significant numbers of progenitor cells were circulating for several days during the recovery period only in the anti-VLA4 treated animals. These data suggest that (1) the effect of anti-VLA4 on mobilization, when used alone, is unlikely to be mediated by secondary cytokine elaboration in vivo; (2) three different cytokines and their combinations do not appear to influence the in vivo responsiveness to anti-VLA4 in coadministration schemes; (3) even if cytokine treatments on their own exert downmodulation of VLA4 function, the target progenitor cells influenced by anti-VLA4 or by cytokines may not necessarily overlap; and (4) augmentation of mobilization in cytokine/anti-VLA4 treatments is most likely caused by an amplification of the pool of target cells on which anti-VLA4 exerts its effects. Because cytokines or anti-VLA4 are each capable of mobilizing long-term repopulating cells and because we show with the present studies that anti-VLA4 in an autologous bone marrow cell transplantation setting does not cause any delay in engraftment, the combination of cytokine/anti-integrin treatment enhancing mobilization may have a clinical use.

Animals↗
PubMed1996

The retinal ganglion cell classes of New World primates.

In the primate retina there are distinct ganglion cell classes, exhibiting particular morphologies and central projections, each responsible for conveying particular types of visual information to the brain. The chief retinal inputs to the cortex arise from specific ganglion cell classes, M-ganglion cells, responsible for carrying the luminance signal, and P-ganglion cells, that convey the red-green color opponent signal, as well as high contrast luminance signal. There are other ganglion cell classes, such as small-field bistratified cells, exhibiting dendrites that stratify at two different levels in the inner plexiform layer, which convey the blue-yellow color opponent signal. Most published data concerning primate retinal ganglion cell anatomy and physiology have been obtained from Old World species. Studies on New World monkeys have recently become of interest since they differ from the Old World monkeys with respect to the color vision inheritance pattern. On reviewing retinal ganglion cell layer organization in New World monkeys, it seems that there are more similarities than differences in relation to the Old World monkeys. Diurnal genera of New World monkeys exhibit a well-developed fovea centralis and ganglion cell density peak, as well as peripheral density values which are in the range reported for Old World monkeys and human. Moreover, all the major ganglion cell classes identified in Old World monkeys are also present in New World primates. Up to now, no obvious anatomical differences between dichromats and trichromats have been reported. The only genus that is significantly different from the others is the Aotus. It exhibits lower ganglion cell density in the central retina, and apparently lacks the small-field bistratified cells.

Animals↗
PubMed1978

Protection of primate lung from stored-blood perfusion by peptidase inhibition and target membrane stabilization.

Microaggregate filtration and separation of the cellular components of stored autologous blood have not changed the functional and morphological damage in primate lungs from stored-blood perfusion. Pharmacologic prevention of these "shock lung" changes was attempted with trasylol and with methylprednisolone pretreatment. In an in situ primate lung perfusion model, fresh and stored blood was perfused in untreated baboons and in groups of seven animals each pretreated with Trasylol or methylprednisolone. Pulmonary damage from stored-blood perfusion was evident by pulmonary edema, increase in pulmonary vascular resistance, decreases in effective compliance and arteriovenous pO2 gradient as well as by morphological criteria. Some protection was afforded by methylprednisolone and, to a lesser extent, trasylol pretreatment against this damage in primate lung form and function induced by stored-blood perfusion.

Animals↗
PubMed1999

Responses to the sensory properties of fat of neurons in the primate orbitofrontal cortex.

The primate orbitofrontal cortex is a site of convergence of information from primary taste, olfactory, and somatosensory cortical areas. We describe the responses of a population of single neurons in the orbitofrontal cortex that responds to fat in the mouth. The neurons respond, when fatty foods are being eaten, to pure fat such as glyceryl trioleate and also to substances with a similar texture but different chemical composition such as paraffin oil (hydrocarbon) and silicone oil [Si(CH3)2O)n]. This is evidence that the neurons respond to the oral texture of fat, sensed by the somatosensory system. Some of the population of neurons respond unimodally to the texture of fat. Other single neurons show convergence of taste inputs, and others of olfactory inputs, onto single neurons that respond to fat. For example, neurons were found that responded to the mouth feel of fat and the taste of monosodium glutamate (both found in milk), or to the mouth feel of fat and to odor. Feeding to satiety reduces the responses of these neurons to the fatty food eaten, but the neurons still respond to some other foods that have not been fed to satiety. Thus sensory-specific satiety for fat is represented in the responses of single neurons in the primate orbitofrontal cortex. Fat is an important constituent of food that affects its palatability and nutritional effects. The findings described provide evidence that the reward value (or pleasantness) of the mouth feel of fat is represented in the primate orbitofrontal cortex and that the representation is relevant to appetite.

Animal Nutritional Physiological Phenomena↗
PubMed2006

Morphological variability within Oesophagostomum bifurcum among different primate species from Ghana.

Adult Oesophagostomum bifurcum (Nematoda: Strongylida) from human and non-human primates from Ghana were compared in order to investigate the extent of morphological variability within the species. Using analysis of variance and principal component analysis, significant differences in morphological characters (such as parasite length, width, length of the oesophagus and length of spicules) were demonstrated between O. bifurcum worms from humans, the Mona, Patas or Green monkey and/or Olive baboons. These findings suggest that O. bifurcum from different species of primate host represent distinct population variants, also supported by recent epidemiological and genetic studies of O. bifurcum from such hosts.

Animals↗
PubMed2003

A survey for helminth parasites in feral New World non-human primate populations and its comparison with parasitological data from man in the region.

A survey for helminth parasites in feral New World non-human primates was conducted and compared with parasitological data from man in the region. A total of 835 fecal samples were collected from feral Aotus nancymae, A. vociferans, Saguinus labiatus, S. mystax, Saimiri boliviensis peruviensis, S. sciureus macrodon, Lagothrix lagotricha and Cacajao calvus rubicundus. In addition, adult parasites were collected from necropsies performed on monkeys that died during quarantine and in captivity. Helminth parasites shared by non-human primates and man in Peru were Ancylostoma braziliensis and Ascaris lumbricoides, found in a captive L. lagotricha; Necator americanus, found in a captive C. calvus rubicundus; Hymenolepis diminuta, found in feral Aotus spp. and S. mystax; and a single Trichuris spp. specimen found in a feral S. sciureus macrodon.

Animals↗
PubMed2004

[Evolution and virulence of primate lentiviruses].

While the AIDS epidemic caused by human immunodeficiency viruses (HIV) has resulted in the death of over 20 million people worldwide, simian immunodeficiency virus (SIV) infection, found in numerous African primate species, does not induce disease symptoms. The factors accounting for this difference between humans and natural host of SIV remain poorly understood. The entangled nature of the host/virus relationship could be the answer, rather than independent virus or host factors. Such a relationship is as a consequence of host/virus adaptation which has evolved over long periods in naturally infected primate species.

Adaptation, Physiological↗
PubMed1996

Occurrence and frequency of transmission of naturally occurring simian retroviral infections (SIV, STLV, and SRV) at the CIRMF Primate Center, Gabon.

Among the primates held at the CIRMF Primate Center, Gabon, no serological sign of SIV infection could be demonstrated in 68 cynomolgus monkeys, 60 chimpanzees, nine gorillas, and 12 sun-tailed monkeys, while seven of 102 mandrills and six of 24 vervets were infected with SIV. Six mandrills, seven vervets and ten cynomolgus monkeys exhibited a full HTLV type 1 Western blot profile. The sera of two gorillas and one chimpanzee presented with a positive but not typical HTLV Western blot profile. The sera of the gorillas lacked p24 antibodies, and the chimpanzee had a Western blot profile evocative of HTLV-II. All attempts to amplify viruses from these animals by PCR were unsuccessful. Two other chimpanzees and seven gorillas presented with indeterminate HTLV Western blot profiles. In the mandrill colony, only male animals were STLV seropositive and no sexual transmission to females was observed. SIV infection was also more frequent in male than female mandrills and sexual transmission appeared to be a rare event. No SRV infection was observed in macaques.

Animals↗
PubMed1996

Brief communication: new primate remains from the Miocene of Namibia, southern Africa.

Miocene primates from southern Africa are extremely rare. For this reason we wish to place on record several interesting new fossil primate specimens recently recovered from the Miocene sites of Berg Aukas and Harasib in the Otavi Mountain region of northern Namibia. The new finds consist of a virtually complete atlas vertebra from Berg Aukas attributable to the hominoid Otavipithecus namibiensis and two teeth and four postcranial fragments from Harasib referrable to Cercopithecoidea. The atlas vertebra exhibits anatomical characteristics intermediate between those of modern cercopithecoids and hominoids which may be indicative of a transition from pronograde to orthograde postures. The cercopithecoid remains show that the earliest Old World monkeys known from southern Africa were small, approximately the size of vervet monkeys. These new specimens are important because they provide the first evidence relating to possible positional behaviors of Otavipithecus and the earliest fossil record of cercopithecoids from southern Africa.

Animals↗
PubMed1997

Comparative primate energetics and hominid evolution.

There is currently great interest in developing ecological models for investigating human evolution. Yet little attention has been given to energetics, one of the cornerstones of modern ecosystem ecology. This paper examines the ecological correlates of variation in metabolic requirements among extant primate species, and uses this information to draw inferences about the changes in energy demands over the course of human evolution. Data on body size, resting metabolism, and activity budgets for selected anthropoid species and human hunter-gatherers are used to estimate total energy expenditure (TEE). Analyses indicate that relative energy expenditure levels and day ranges are positively correlated with diet quality; that is, more active species tend to consume more energy-rich diets. Human foragers fall at the positive extremes for modern primates in having high expenditure levels, large ranges, and very high quality diets. During hominid evolution, it appears that TEE increased substantially with the emergence of Homo erectus. This increase is partly attributable to larger body size as well as likely increases in day range and activity level. Assuming similar activity budgets for all early hominid species, estimated TEE for H. erectus is 40-45% greater than for the australopithecines. If, however, it is assumed that the evolution of early Homo was also associated with a shift to a more "human-like" foraging strategy, estimated expenditure levels for H. erectus are 80-85% greater than in the australopithecines. Changing patterns of resource distribution associated with the expansion of African savannas between 2.5 and 1.5 mya may been the impetus for a shift in foraging behavior among early members of the genus Homo. Such ecological changes likely would have made animal foods a more attractive resource. Moreover, greater use of animal foods and the resulting higher quality diet would have been important for supporting the larger day ranges and greater energy requirements that appear to have been associated with the evolution of a human-like hunting and gathering strategy.

Animals↗
PubMed1997

Primate natal coats: a preliminary analysis of distribution and function.

Pelage coloration of infants was compiled for 138 species of primates. Three functional hypotheses--alloparental, infant defense, and paternity cloak--for primate natal coats are tested. Neonatal pelage contrasted with adult pelage in over half of the species examined. Subtle or inconspicuous contrast was more common than flamboyant contrast. Natal coats began to change at 5.7 weeks and disappeared by 18.0 weeks postpartum on average. The first body part to lose natal coloration was the head and/or dorsum in the majority of species. Functional analyses provided no support for the only published hypothesis--alloparental--while providing partial support for two new hypotheses--infant defense and paternity cloak. A significant association between testes weight and natal coat contrast supports a link between mating system and infant contrast. This is discussed in terms of infanticide avoidance. Natal coats are proposed to be categorically differentiated into inconspicuous and flamboyant types, not differentiated by a continuous gradation, such as color. Subspecific differentiation and patterns of shared ancestry are assessed.

Animals↗
PubMed1998

Technical note: Modeling primate occlusal topography using geographic information systems technology.

Most functional analyses of primate tooth form have been limited to linear or area measurements. Such studies have offered but a limited glimpse at differences in occlusal relief among taxa. Such differences in dental topography may relate to tooth function and, so, have considerable implications for the inference of diet from fossil teeth. In this article, we describe a technique to model and compare primate molars in three dimensions using Geographic Resources Analysis Support System (GRASS) software. We examine unworn lower second molars of three extant hominoids with known differences in diet (Gorilla gorilla, Pan troglodytes, and Pongo pygmaeus), and two fossil forms, (Afropithecus turkanesis and Dryopithecus laietanus). First, we obtained approximately 400 landmarks on the occlusal surfaces of each tooth using an electromagnetic digitizer. Raster "terrain models" of occlusal surfaces were then created by interpolation of the coordinate data. We used GRASS terrain analysis automated techniques to quantify the volumes and slopes of individual cusps. We also used the GRASS watershed technique to identify the volume of liquid that would accumulate in each tooth's basin (a measure of basin area), and the directions and intensity of drainage over the occlusal surface. In sum, GRASS shows considerable potential for the characterization and comparison of tooth surfaces. Furthermore, techniques described here are not limited to the study of teeth, but may be broadly applicable to studies of skulls, joints, and other biological structures.

Animals↗