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PubMed1985

Early implantation stages in the marmoset monkey (Callithrix jacchus).

The morphology of the initial stages of implantation in the marmoset monkey (Callithrix jacchus) was studied by obtaining embryos and associated endometrium at timed intervals after ovulation. Estrus cycles were detected by measuring daily levels of plasma progesterone. Following a short follicular phase, circulating levels of progesterone above 20 ng/ml were taken as representing day 1 after ovulation. On this basis, single, twin, and triplet embryos were recovered from six perfused-fixed females on days 13, 16, 19, 23, and 29 after ovulation and prepared in resin for light microscopy. Early implantation stages, 13 and 16 days after ovulation, were characterized by the intrusion of syncytial trophoblast between epithelial cells of the endometrium with minimal cellular damage. Some hyperplasia of epithelium at the margin of the implantation site was evident. The consolidation of the initial attachment was achieved by an increase in syncytial trophoblast underlying the inner cell mass of the embryo which rapidly surrounded and breached maternal capillaries. Although initially separate, the chorions of twin or triplet embryos started to fuse by day 19 after ovulation. This process was complete by day 29 such that embryos shared a common uterine exocoelom surrounded by continuous trophoblast. It was concluded that implantation in the marmoset monkey commenced on days 11-12.5 after ovulation and involved an intrusive mechanism. Although trophoblast penetration of endometrium was superficial, maternal capillaries were tapped at an early stage of implantation. The fusion of chorions of twins and triplets first occurred around day 19 after ovulation.

Animals↗
PubMed2007

Radiographic evaluation of neonatal skeletal development in Callimico goeldii reveals closer similarity to Callithrix jacchus than to Saguinus oedipus.

The phylogenetic affinities of the neotropical Goeldi's monkey (Callimico goeldii) have long been a matter of debate. Whereas most morphological evidence appears to place Callimico in a sister group position relative to the Callitrichidae, genetic studies place C. goeldii within the Callitrichidae and suggest that it is more closely related to marmosets than to tamarins. The present study presents the first radiographic analysis comparing the secondary limb bone ossification of newborn C. goeldii with representatives of the marmosets (Callithrix jacchus) and tamarins (Saguinus oedipus). The state of secondary ossification of the epiphysis and short bones is classified into three different ontogenetic stages. Our results reveal that in terms of the number of ossification centers, C. goeldii is significantly closer to C. jacchus than to S. oedipus. This is the first morphological study to support the findings of molecular studies, and the results suggest that C. goeldii is more closely related to marmosets than to tamarins.

Animals↗
PubMed1988

Kin preference in marmosets and tamarins: Saguinus oedipus and Callithrix jacchus (Callitrichidae, primates).

Field studies on callitrichid primates have suggested that some species may exhibit a communal breeding system in which two or more males mate with a single female and cooperatively participate in infant rearing. However, high levels of aggression have been observed between males under both laboratory and field conditions. In avian models for communal breeding, cooperating males are often closely related. In a laboratory test of a hypothesis of the amelioration of aggression based on kinship, four mated pairs of both Saguinus oedipus and Callithrix jacchus were introduced to both novel male conspecifics and to their own male siblings, from whom they had been separated for a minimum of 4 months. Significant differences (P less than .01) were seen in the responses of the two species to male conspecifics generally: S. oedipus males responded to intruders with overt aggression significantly more frequently than did marmosets while C. jacchus males more frequently scent-marked than did tamarins. Evidence of preference for kin males was seen in the significantly decreased frequencies of these behaviors in the presence of kin males over those observed in the presence of novel males. It is argued that, under field conditions, cooperation between male callitrichids may be facilitated by kinship. Further, twin births, short gestation lengths, and interbirth intervals seen in callitrichid primates all contribute to the number of socially familiar kin with which an individual animal might cooperate.

Age Factors↗
PubMed1976

Epstein-Barr virus: experimental infection of Callithrix jacchus marmosets.

Eight common marmoset monkeys (Callithrix jacchus) were inoculated with about 10(4) transforming units of B95-8 virus; seven of the marmosets died 50-111 days post inoculation and all seven showed microscopic and/or macroscopic lesions compatible with a diagnosis of lymphoproliferative disease. Low levels of anti-VCA antibodies were detected in plasma from six marmosets. Attempts failed to establish continuous EBV-carrying lymphoblastoid cell cultures by cultivation in vitro of circulating lymphocytes or minced lymphoid tissues obtained at necropsy.

Animals↗
PubMed2000

Variation in steroid hormones associated with infant care behaviour and experience in male marmosets (Callithrix kuhlii).

We describe temporal patterns of change in paternal behaviour and urinary concentrations of the steroid hormones testosterone (T) and oestradiol (E(2)) in male black tufted-ear marmosets, Callithrix kuhlii, relative to the birth of their young, and test predictions of the hypotheses that (1) high levels of T are incompatible with paternal care and (2) levels of T and E(2)vary with a father's prior experience in his family group. After young were born, levels of urinary T and E(2)remained near prepartum concentrations and rates at which fathers carried infants were below peak levels until the approximate time that postpartum mating ordinarily occurs, suggesting a possible trade-off between readiness to mate and paternal behaviour in C. kuhlii. Infant-carrying behaviour of fathers occurred at its highest rate 3-4 weeks after parturition and coincided with significant declines in urinary levels of T and E(2), providing preliminary support for the hypothesis that these hormones are antagonistic to paternal behaviour. Urinary T and E(2)declined among fathers regardless of whether their young survived to weaning or died at birth, indicating that variation in these hormones after parturition occurs even in the absence of continued stimuli from infants. When adjusted for declines ordinarily associated with aging, urinary T tended to be lower among fathers with a great deal of prior experience caring for young compared with fathers having little or no experience, suggesting that either experience affects T levels of fathers, or that T levels influence fathers' chances of successfully rearing infants. Overall, our results suggest that in male C. kuhlii, T, and possibly E(2), play an important role in balancing the expression of paternal care with that of other reproductive behaviours. Copyright 2000 The Association for the Study of Animal Behaviour.

Journal Article↗
PubMed1991

Ultrastructural and histochemical characterization of marmoset (Callithrix jacchus) Leydig cells during postnatal development.

Leydig cell development was investigated in the marmoset (Callithrix jacchus) testis from 24 h post partum (pp) up to sexual maturity, using ultrastructural and histochemical methods. Electron microscopically three different Leydig cell (LC) types could be distinguished: neonatal, immature and adult LCs. Neonatal LCs exhibited a round nucleus, large tubular mitochondria, abundant smooth endoplasmic reticulum (SER), and few small fat vesicles. The typical immature LCs showed a lobulated nucleus, smaller tubulo-vesicular mitochondria, less SER, and larger fat vesicles. Adult LCs contained an invaginated nucleus, tubular mitochondria, abundant SER, large fat vesicles, and lipofuscin granules. Neonatal Leydig cells occurred from 24 h pp up to 10 weeks pp, immature LCs from 2 weeks pp up to 20 weeks pp, and adult LCs from 20 weeks onwards. The appearance of a new LC population was accompanied by a numeric decrease and occurrence of regressive cells of the previous population. Developmental steps of differentiation were recognizable in the population of immature and adult LCs by the amount of SER (immature LCs), the size of mitochondria (adult LCs), and the morphology of the nucleus at the beginning of their appearance. Activity of 3 beta-hydroxysteroid dehydrogenase (3 beta-HSD) was moderate in immature LCs from 2 weeks pp to 12 weeks pp and strong in adult LCs. Neonatal LCs were not stained nor were immature LCs from 16 weeks to 20 weeks. Comparison of the ultrastructural classification of LCs and the activity of 3 beta-HSD showed that the capacity for steroid biosynthesis does not necessarily include morphological differences. Activity of non-specific esterase (nE) was found in LCs except of the period between 16 and 25 weeks pp. A transient decrease of activity was seen during the first week of life. Both, the phase of decrease and the phase of inactivity were followed by distinct activation of nE. Lipid content and the size of single fat droplets in LCs, as seen with Sudan black staining, varied during postnatal development. Finely stained granules were typical for neonatal LCs, whereas larger droplets were found in immature and adult cells. Particularly high amounts of lipids were seen at one week and between 32-60 weeks pp, which was the regression of neonatal LCs, showing ultrastructurally higher amounts of lipids than intact neonatal LCs. High amounts of lipid during puberty (32-60 weeks pp) accompanied by an activation of nE at the onset of puberty suggest an initiative role in steroidogenesis.(ABSTRACT TRUNCATED AT 400 WORDS)

3-Hydroxysteroid Dehydrogenases↗
PubMed1991

Topographical and topological organization of the thalamocortical projection to the striate and prestriate cortex in the marmoset (Callithrix jacchus).

In eleven hemispheres of nine marmoset monkeys (Callithrix jacchus), we have investigated the thalamo-cortical organization of the projections from the pulvinar to the striate and prestriate cortex. In each experiment, single or multiple injections of various retrograde fluorescent tracers were injected into adjacent regions or areas. In two experiments, horseradish peroxidase (HRP) was injected into the lateral geniculate nucleus (LGN) and the lateral pulvinar, respectively. The results show that the thalamo-cortical projection from LGN to striate cortex and from pulvinar to the prestriate cortex are similarly organized, but the geniculo-striate projection is more precise than the pulvinar-prestriate projection. The pulvinar-prestriate projection is topographically organized and preserves topological neighbourhood relations. Projection zones to the various visual areas are concentrically wrapped around each other. The projection zone to area 18 constitutes a central core region. It begins ventro-laterally in PuL where the pulvinar is in contact with the LGN. This contact zone we called the hilus region of the pulvinar. The area 18-projection zone stretches as a central cone into the posterior pulvinar through PuL and into PuM. It is surrounded by the projection zone to the posterior belt of area 19 and this in turn is surrounded by the projection zone to the anterior belt of area 19. The projection zones to area 19 are then surrounded medially and dorsally by zones projection to the temporal and parietal association cortex, respectively. The projection zone to area MT is located medio-ventrally in the posterior pulvinar (PuIP and surrounding nuclei) and coincides with a densely myelinated region. Area 17 also receives input from the pulvinar but probably predominantly in the region of the central visual field. The pulvinar zone projecting to area 17 is located ventrolaterally from the central core region projecting to area 18 and is contiguous laterally with the LGN. If the positions of the vertical and the horizontal meridian in the pulvinar correspond to those in the respective cortical projection zones, a second order visual field representation such as found in area 18, with the horizontal meridian split at an eccentricity of about 7-10 degrees, can also be recognized in the pulvinar.

Acetylcholinesterase↗
PubMed1991

The local domain for divergence of subcortical afferents to the striate and extrastriate visual cortex in the common marmoset (Callithrix jacchus): a multiple labelling study.

In the common marmoset (Callithrix jacchus), the cortical projection from the pulvinar and other diencephalic structures into the striate and prestriate cortex was investigated with various fluorescent retrograde tracers. Single cortical injections as well as multiple injections at distances of 1-2 mm with one tracer into an extended but coherent cortical region were applied. Fields with multiple injections were placed so that they touched each other (minimal distances 2 to 3 mm). Retrogradely labelled cells in the LGN and/or the pulvinar were arranged in coherent columns, volumes or slabs, but cell volumes resulting from neighbouring cortical injections overlapped at their border (for details of the thalamo-cortical topography see the companion paper Dick et al. (1991]. Double labelled cells (dl) were only found in the zones of overlap of the cell volumes labelled by the respective tracers. The relative number of dl-cells in these overlap zones was 6.2 +/- 3.1%. The dl-frequency was the same in the various nuclei of the pulvinar and the LGN. In the main layers of LGN, dl-cells were found only in the overlap zone of two injection fields into area 17, but a few dl-cells were found in interlaminar cells after injections into area 17 and 18. Maximal cortical distances between injection fields which produced dl in the pulvinar, were 3 to exceptionally 4 mm but dl was highest at injection distances less than or equal to 2.5 mm and decreased sharply at wider distances. Such overlap zones were concerned with identical or overlapping regions of visual field representation in the cortex and probably also in the pulvinar. Although in individual experiments up to four different tracers were injected into different striate/prestriate regions, often embracing the same visual field representation, individual cells in the pulvinar showed dl from maximally only two tracers injected into neighbouring cortical regions. We conclude that dl in the posterior thalamic projection nuclei is determined essentially by cortical distance and thus reflects the local domain of branching of thalamo-cortical afferents. Pruning of such branches during development may further restrict bifurcating axons to identical visual field representations, but representation of identical visual field regions in different visual areas is not, per se, a sufficient condition for dl. It is not found if such regions are further apart from each other than the typical local domain of 2-3 mm, exceptionally up to 4 mm in one experiment after injections into area 17 and MT.(ABSTRACT TRUNCATED AT 400 WORDS)

Afferent Pathways↗
PubMed1980

A stereotaxic x-ray map of the hypothalamus of the marmoset monkey Callithrix jacchus.

Precise hypothalamic surgery in the marmoset monkey Callithrix jacchus cannot be performed by means of the Horsley-Clarke stereotaxic procedure. Thus, a simple stereotaxic X-ray technique was developed. Technical requirements are a stereotaxic frame for small animals and a dental X-ray source. A sagittal map shows hypothalamic structures in relation to surrounding bony landmarks. Corresponding coronal plates allow target determination in that plane. Intracerebral coordinates based on the position of the optic chiasma can be transformed into individual Horsley-Clarke coordinates. The error of the atlas is estimated as +/- 0.25 mm anteroposteriorly, +/- 0.1 mm coronally, and +/- 0.5 mm vertically.

Animals↗
PubMed1976

Comparative autoradiographic and metabolic study of delta8- and delta9-tetrahydrocannabinol in the brain of the marmoset Callithrix jacchus.

The label distribution in the brain of the marmoset Callithrix jacchus following intravenous application of radioactively labeled delta8-tetrahydrocannabinol (delta8-THC) and delta9-THC is investigated by autoradiographic technique. Accumulations of label are observed in nuclei concerned with motor function, in the optic and acoustic pathways, and a few other structures. Of the two hydroxylated isomeres which were shown to be equally psychoactive the brain concentration of 11-OH-delta9-THC was found to be about 3 times higher as compared with 11-OH-delta8 THC, which may explain why delta9-THC is more potent than delta8-THC. More than 90% of the radioactivity found in the brain can be attributed to the THCs and their 11-hydroxylated isomeres. Polar metabolites are almost completely absent from the brain.

Animals↗
PubMed1975

Metabolism and autoradiographic distribution of delta-8- and delta-9-tetrahydrocannabinol in some organs of the monkey Callithrix jacchus.

Metabolism and autoradiographic distribution of the two isomeric tetrahydrocannabinols, (2,4-14-C)-delta-8-THC and (2,4-14-C)-delta-9-THC, were studied in the marmoset Callithrix jacchus. Of the two cannabinoids, delta-8-THC had a slower initial rate of biotransformation to the psychopharmacologically more potent 11-hydroxylated metabolite. This may explain the minor psychopharmacological activity of the delta-8-isomer. In glandular tissues an accumulation of unchanged delta-9-THC was observed. Autoradiography revealed characteristic label distributions in some organs 30 min after the administration of the drugs. This labelling pattern was found to be changed after a 6-hr incorporation period. The autoradiographic distribution of delta-8 and delta-9-THC appeared to be identical.

Adrenal Glands↗
PubMed1975

The effect of an immunosuppressive drug (azathioprine) on the latent infection of marmoset monkeys (Callithrix jacchus) with the oncogenic Herpesvirus saimiri.

Callithrix jacchus (CJ) marmoset monkeys can be latently infected with Herpesvirus saimiri (HVS). In order to determine whether this resistance to the oncogenic potential of HVS could be due to the immune surveillance, azathioprine, a known immunosuppressive drug, was given to 7 latently infected CJ marmosets. The animals died within 147 days probably from side effect caused by azathioprine, but no animal developed a tumor.

Animals↗
PubMed1991

Polyhalogenated dibenzo-p-dioxins and dibenzofurans and the immune system. 2. In vitro effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on lymphocytes of venous blood from man and a non-human primate (Callithrix jacchus).

The effect of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on poke weed mitogen-stimulated proliferation and differentiation of peripheral lymphocytes was studied in vitro with cells from a non-human primate (marmoset monkey, Callithrix jacchus) and from man. Monoclonal antibodies and flow cytometry (FACScan) were used for analysis. The extent of the overall mitogen-stimulated proliferation of isolated lymphocytes in vitro from marmoset blood was only slightly reduced in the presence of TCDD compared to the solvent control (0.01% DMSO). However, incubation with TCDD in the culture medium together with the mitogen led to a pronounced decrease in the percentage of the lymphocyte subset with the surface marker CD4, and a concomitant increase in the percentage of CD8+ cells. The lowest concentration found to be effective in vitro was 1 x 10(-13) M TCDD (25 fg TCDD/ml). When culturing lymphocytes from human blood of different donors under identical conditions in the presence of TCDD and the mitogen, corresponding effects were observed to those seen with marmoset cells. A closer analysis of the T lymphocyte subsets affected revealed the CD4+ CDw29+ (helper-inducer cells) to be the main target for the action of TCDD. A clear-cut change in the percentage of this subpopulation was induced at concentrations as low as 1 x 10(-13) M TCDD. The development of the IL-2-marker in culture was only slightly affected by TCDD, and concentrations of 1 x 10(-12) M were required to slightly reduce the number of CD2+CD25+ cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1983

Isolation, characterization and comparative aspects of the major serum apolipoproteins, B-100 and AI, in the common marmoset, Callithrix jacchus.

The two major apolipoproteins of marmoset serum have been isolated and characterized, and on the basis of physicochemical and immunological criteria are homologous with the human AI and B-100 proteins. Marmoset apolipoprotein AI was the principal protein of high-density lipoproteins (HDL) and was purified by gel filtration chromatography and electrophoresis in alkaline-urea polyacrylamide gel followed by electrophoretic elution. Purified marmoset apolipoprotein AI displayed an Mr of approx. 27000, was polymorphic (five forms) on isoelectric focussing, with pI values in the range 4.8-5.0, and migrated similarly to human apolipoprotein AI in alkaline-urea gels. An overall resemblance was seen in the amino acid composition of marmoset apolipoprotein AI and that of its human counterpart with the notable exception that marmoset AI contained 1 isoleucine residue/mole. An immunological reaction of partial identity between the human and monkey proteins was seen upon immunodiffusion of their HDLs against antiserum to human apolipoprotein AI. Marmoset B-100 was the predominant apoprotein of VLDL and LDL, resembling the human protein in its elution profile on gel filtration chromatography in anionic detergent, and in its high apparent Mr (approx. 520000). The marmoset and human B-100 proteins were alike in amino acid composition and carbohydrate content. Moreover, their immunological behaviour with an antiserum to marmoset apolipoprotein B showed them to share certain antigenic determinant(s). We conclude that the physicochemical properties of the principle apolipoproteins of Callithrix jacchus, a New World primate, markedly resemble those of the human AI and B-100 proteins, suggesting therefore that they may function similarly in lipid transport and metabolism. Counterparts to human apolipoproteins AII, E, CII and CIII have also been tentatively identified.

Amino Acids↗
PubMed1986

Platelet measurements in the common marmoset, Callithrix jacchus.

Platelet counts and mean platelet volumes were determined for 39 male and 32 female adult marmoset whole blood samples and these results are compared with previously published data. There is no evidence of a difference between sexes but there is some evidence of a relationship between platelet count and mean platelet volume in the Callithrix jacchus population studied.

Aging↗
PubMed1990

Monoclonal antibodies from Epstein-Barr virus-transformed lymphocytes of common marmosets (Callithrix jacchus) immune to malaria.

The B lymphocytes of the common marmoset Callithrix jacchus can be immortalized by infection with Epstein-Barr virus (EBV) in vitro (Desgranges et al., 1976). C. jacchus is susceptible to infection with the blood stages of several species of malaria parasite including the line designated MVF1 (Mitchell et al., 1988) from which it recovers and shows immunity to reinfection. By exploiting these two phenomena, EBV-transformed, marmoset lymphoblastoid cell lines secreting antibodies to malaria parasite antigens have been generated and cloned. We believe this to be the first time that monoclonal antibodies (MAbs) have been raised from common marmosets. Since numerous and diverse human pathogens can infect this small primate in the laboratory, these methods may prove generally applicable for the generation of MAbs whose specificities derive from immune responses to infection.

Animals↗
PubMed1989

Tissue specific differences in the fatty acid composition of the marmoset monkey (Callithrix jacchus).

1. The possible relationship between the fatty acid composition of the adipose tissue of the marmoset monkey (Callithrix jacchus) and its dietary lipid intake was examined after a long-term feeding trial. 2. Only the proportions of stearic and linoleic acid in the adipose tissue were similar to those in the diet. The proportions of all other saturated and unsaturated fatty acid components were significantly different thus greatly reducing the potential value of this relationship in the marmoset. 3. The phospholipid fatty acid profiles of cardiac and skeletal muscle, aortae, kidney, liver, lung and brain were also compared to those of the plasma, platelets or red blood cells. 4. With the exception of the liver where the fatty acid profile is similar to that of the plasma, no clear relationships were found between the fatty acid profiles of these tissues and the components of the blood. 5. The fatty acid composition of skeletal muscle was very similar to that of the cardiac muscle of the marmoset, suggesting that muscle biopsy might be useful as an index of cardiac muscle composition.

Adipose Tissue↗