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[studies on the wild reservoirs and vectors of trypanosoma cruzi. lxv. natural infection of the monkey callithrix geoffroyi (humboldt, 1812) by t. cruzi]. 1977406646
density and habitat use of primates at an atlantic forest reserve of southeastern brazil.about 58.3 km of transects were surveyed throughout 21,800 ha of an atlantic forest reserve of southeastern brazil, yielding habitat preference data and density estimates for three of the four primate species present. the densities were calculated using the "fourier series estimator" and were 10.5, 2.2 and 1.2 groups/km2 for callithrix geoffroyi, cebus apella robustus and callicebus personatus personatus, respectively. alouatta fusca fusca although present, was not seen during the survey. c. geo ...19957569145
field observation of a group of geoffroy's marmosets mobbing a margay cat. 19958529974
activity budget of geoffroy's marmoset (callithrix geoffroyi) in an atlantic forest in southeastern brazil.this report describes the activity budget of a group of callithrix geoffroyi in a patch of atlantic forest on the brazilian coast, between february 1993 and january 1994, using the scan sampling methods. on average, the group rested for 29% of the daylight hours, fed for 21%, moved for 20%, and foraging and gouging occupied 14% and 13% of this period, respectively. a greater proportion of time was spent resting during the wet seasons (32.1%) than the dry seasons (17.8%), but the reverse observed ...19989839906
demonstration of a foraging advantage for trichromatic marmosets (callithrix geoffroyi) dependent on food colour.it has been suggested that the major advantage of trichromatic over dichromatic colour vision in primates is enhanced detection of red/yellow food items such as fruit against the dappled foliage of the forest. this hypothesis was tested by comparing the foraging ability of dichromatic and trichromatic geoffroy's marmosets (callithrix geoffroyi) for orange- and green-coloured cereal balls (kix) in a naturalized captive setting. trichromatic marmosets found a significantly greater number of orange ...200010737399
plasticity of human chromosome 3 during primate evolution.comparative mapping of more than 100 region-specific clones from human chromosome 3 in bornean and sumatran orangutans, siamang gibbon, and old and new world monkeys allowed us to reconstruct ancestral simian and hominoid chromosomes. a single paracentric inversion derives chromosome 1 of the old world monkey presbytis cristata from the simian ancestor. in the new world monkey callithrix geoffroyi and siamang, the ancestor diverged on multiple chromosomes, through utilizing different breakpoints ...200414706448
pterygodermatites nycticebi (nematoda: rictulariidae): accidental detection of encapsulated third-stage larvae in the tissue of a white-fronted marmoset.twin, white-fronted marmosets (callithrix geoffroyi) born and raised in a zoo in japan died at 7 mo of age. several encapsulated nematode larvae were detected in the intestinal wall, as well as a few in the mesenteric lymph nodes of 1 of the twins. in the other marmoset, no encapsulated nematode larva was detected in the organs, but many adult pterygodermatites nycticebi were found in the intestinal lumen. in the past 5 yr, 5 primates kept in the same zoo, i.e., 1 squirrel monkey (saimiri sciure ...200314740905
quantitative data on training new world primates to urinate.this study assessed the effectiveness of operant conditioning in training three species of captive callitrichid primates (leontopithecus rosalia, callithrix geoffroyi, and saguinus imperator) to urinate on demand. there were three goals to the study: 1) to develop a system for quantitatively assessing positive reinforcement training; 2) to ascertain whether or not positive reinforcement techniques can be used to train callitrichid monkeys to urinate on demand, and if so, how many training sessio ...200415356860
pseudomonas simiae sp. nov., isolated from clinical specimens from monkeys (callithrix geoffroyi).an unusual gram-negative, catalase- and oxidase-positive, rod-shaped bacterium isolated from different clinical samples from two monkeys (callithrix geoffroyi) was characterized by phenotypic and molecular genetic methods. the micro-organism was tentatively identified as a pseudomonas species on the basis of the results of cellular morphological and biochemical tests. fatty acid studies confirmed this generic placement and comparative 16s rrna gene sequencing studies demonstrated that the unknow ...200617082409
a foraging advantage for dichromatic marmosets (callithrix geoffroyi) at low light intensity.most new world monkey species have both dichromatic and trichromatic individuals present in the same population. the selective forces acting to maintain the variation are hotly debated and are relevant to the evolution of the 'routine' trichromatic colour vision found in catarrhine primates. while trichromats have a foraging advantage for red food compared with dichromats, visual tasks which dichromats perform better have received less attention. here we examine the effects of light intensity on ...201019740895
Stress reactivity in young marmosets (Callithrix geoffroyi): Ontogeny, stability, and lack of concordance among co-twins.Variation in response styles in the hypothalamic-pituitary-adrenal (HPA) axis are known to be predictors of short- and long-term health outcomes. The nature of HPA responses to stressors changes with developmental stage, and some components of the stress response exhibit long-term individual consistency (i.e., are trait-like) while others are transient or variable (i.e., state-like). Here we evaluated the response of marmoset monkeys (Callithrix geoffroyi) to a standardized social stressor (soci ...201122210196
natural variation in gestational cortisol is associated with patterns of growth in marmoset monkeys (callithrix geoffroyi).high levels of prenatal cortisol have been previously reported to retard fetal growth. although cortisol plays a pivotal role in prenatal maturation, heightened exposure to cortisol can result in lower body weights at birth, which have been shown to be associated with adult diseases like hypertension and cardiovascular disease. this study examines the relationship between natural variation in gestational cortisol and fetal and postnatal growth in marmoset monkeys. urinary samples obtained during ...201222212825
vector-borne transmission of trypanosoma cruzi among captive neotropical primates in a brazilian zoo.neotropical primates are important sylvatic hosts of trypanosoma cruzi, the etiological agent of chagas disease. infection is often subclinical, but severe disease has been described in both free-ranging and captive primates. panstrongylus megistus, a major t. cruzi vector, was found infesting a small-primate unit at brasília zoo (zoob), brazil. zoob lies close to a gallery-forest patch where t. cruzi circulates naturally. here, we combine parasitological and molecular methods to investigate a f ...201626813657
cutting costs in response to predatory threat by geoffroy's marmosets (callithrix geoffroyi).ideally, prey should respond to their predators efficiently, without over- or underreacting to the threat. this may be particularly important for small-bodied species for whom metabolic demands are high and predatory risk is great. in the current study, two family groups of callithrix geoffroyi living outside in a rural setting at the center for reproduction of endangered species, san diego wild animal park, were observed before, during, and after ten presentations of a great horned owl model. t ...19989802510
hawk calls elicit alarm and defensive reactions in captive geoffroy's marmosets (callithrix geoffroyi).most descriptions of callitrichid antipredator behavior have come from observations of visual encounters with predators, but there is also anecdotal evidence suggesting that callitrichids may use auditory cues associated with raptors for the early detection of potential danger. in the present study, geoffroy's marmosets consistently reacted to the tape-recorded calls of a red-tailed hawk (buteo jamaicensis) with high-intensity antipredator behaviors. compared to the taped calls of a raven (corvu ...201412826731
fecal glucocorticoid metabolite responses to management stressors and social change in four species of callitrichine monkeys.the use of enzyme immunoassays (eia) for the non-invasive measurement of glucocorticoids provides a valuable tool for monitoring health and welfare in sensitive species. we validated methods for measuring fecal glucocorticoid metabolites (fgm) using the response to veterinary exams for four species of callitrichine monkeys: golden lion tamarin (leontopithecus rosalia, n = 7), callimico (callimico goeldii, n = 2), pied tamarin (saguinus bicolor, n = 2), and white-fronted marmoset (callithrix geof ...201626831854
prenatal androgen exposure and parental care interact to influence timing of reproductive maturation in marmosets.the timing of reproductive maturation is susceptible to hormonal and environmental influences, and variation in this timing can be partially attributed to the prenatal and post-natal environment. we examined associations between prenatal steroid exposure and the post-natal family environment on the variability in reproductive maturation timing in young marmosets (callithrix geoffroyi). urine samples from pregnant females were analyzed for cortisol (cort) and androgens (ua). post-natal ua was mea ...201727643386
behavioral responses to social separation stressor change across development and are dynamically related to hpa activity in marmosets.psychosocial stressors activate two distinct stress-response systems, a central, behavioral response, and a peripheral, endocrine response. both behavioral and endocrine responses to stressors are subject to individual and developmental variables, but it is not known whether stressor induced behaviors are stable across development, and how they correspond with changes in the endocrine component of the stress response. we characterized the development and stability of behavioral responses to a mi ...201424532179
quality of maternal and paternal care predicts later stress reactivity in the cooperatively-breeding marmoset (callithrix geoffroyi).variation in the early postnatal social environment can have lasting effects on hypothalamic-pituitary-adrenal (hpa) axis stress responses. both rats and macaque monkeys subjected to low quality or abusive maternal care during the early postnatal period have more pronounced hpa responses to environmental stressors throughout development and into adulthood compared to animals reared in higher quality early maternal environments. however, little is known about the relative contributions to hpa str ...201324099861
post-partum variation in the expression of paternal care is unrelated to urinary steroid metabolites in marmoset fathers.the organization and activation of maternal care are known to be highly regulated by hormones and there is growing evidence that expression of paternal care is also related to endocrine substrates. we examined the relationship between paternal behavior and steroid hormones in marmoset fathers (callithrix geoffroyi) and evaluated whether hormone-paternal behavior relationships were altered by previous offspring-care experience in males. based on previous findings, we predicted that testosterone, ...201323439223
describing ovarian cycles, pregnancy characteristics, and the use of contraception in female white-faced marmosets, callithrix geoffroyi.endocrine data and characteristics of nonconceptive ovarian cycling and pregnancy are limited within the genus callithrix to the common marmoset (c. jacchus) and wied's black tufted-ear marmoset (c. kuhlii). this article presents patterns of urinary pregnanediol-3-glucuronide (pdg) excretion, as determined by enzyme immunoassay, throughout the course of ovarian cycling and pregnancy in white-faced marmosets (c. geoffroyi). furthermore, characteristics of reproductive parameters including litter ...201222865351
maternal gestational androgens are associated with decreased juvenile play in white-faced marmosets (callithrix geoffroyi).exposure to androgens during prenatal development shapes both physiological and behavioral developmental trajectories. notably, in rhesus macaques, prenatal androgen exposure has been shown to increase rough-and-tumble play, a prominent behavioral feature in males during the juvenile period in primates. while macaques are an old world, polygamous species with marked sexually dimorphic behavior, new world callitrichine primates (marmosets and tamarins) live in cooperative breeding groups and are ...201222705955
social isolation affects partner-directed social behavior and cortisol during pair formation in marmosets, callithrix geoffroyi.pair-bonded relationships form during periods of close spatial proximity and high sociosexual contact. like other monogamous species, marmosets form new social pairs after emigration or ejection from their natal group resulting in periods of social isolation. thus, pair formation often occurs following a period of social instability and a concomitant elevation in stress physiology. research is needed to assess the effects that prolonged social isolation has on the behavioral and cortisol respons ...201121712050
social and developmental influences on urinary androgen levels in young male white-faced marmosets (callithrix geoffroyi).callitrichine primates (marmosets and tamarins) often remain in their natal groups beyond the time of sexual maturity. although studies have characterized the development of female reproductive function in callitrichine offspring, less is known about the male reproductive development. to document reproductive development in male marmosets, we monitored urinary androgen (ua) excretion in males housed in a captive colony of white-faced marmosets (callithrix geoffroyi). young male marmosets showed ...201121328596
maternal androgen levels during pregnancy are associated with early-life growth in geoffroy's marmosets, callithrix geoffroyi.fetal development is a critical period of physical development, and factors in the intrauterine environment can cause lasting effects on the growth and development of offspring. there is little research evaluating organizational effects of early androgen exposure of endogenous maternal origins on the prenatal and postnatal growth of offspring. we evaluated the association between maternal androgen levels during gestation and pre- and postnatal growth of offspring. maternal androgen levels in mar ...201019854190
maternal gestational androgen levels in female marmosets (callithrix geoffroyi) vary across trimesters but do not vary with the sex ratio of litters.maternal hormones can dramatically modify offspring phenotypes via organizational actions on morphological and behavioral development. in placental mammals, there is the possibility that some portion of hormones in maternal circulation may be derived from fetal origin. we tested the possibility that maternal androgens in pregnant female marmosets reflected, in part, contributions from male fetuses by comparing levels of urinary androgens across pregnancy in females carrying varying numbers of ma ...201019646445
hand preference predicts reactions to novel foods and predators in marmosets (callithrix geoffroyi).in chimpanzees (pan troglodytes) and common marmosets (callithrix jacchus), left-handed individuals are less likely than right-handed individuals to explore new objects and situations, suggesting a relationship between the hemispheric specialization of emotional states and motor function. to further explore this relationship and to test the hypothesis that fearfulness is related to hand preference, we assessed willingness to approach, sniff, and taste novel foods, and the duration of freeze reac ...200919236141
pre-retirement predator encounters alter the morning behavior of captive marmosets (callithrix geoffroyi).limited data are available on the long-term effect an encounter with a predator has on its potential prey. anecdotal reports from field research indicate that even unsuccessful attacks by predators on callitrichids have long-lasting effects. the subjects for this study were two groups of geoffroy's marmosets (callithrix geoffroyi) housed outside, off exhibit, at the center for reproduction of endangered species at the san diego wild animal park. before they retired in the evening, the marmosets ...200415195329
home range of a geoffroy's marmoset group, callithrix geoffroyi (primates, callitrichidae) in south-eastern brazil.the home range of one group of the geoffroy's marmoset (callithrix geoffroyi) was studied in a fragment of the atlantic forest in south-eastern brazil, between february 1993 and january 1994. the total home range was 23.3 ha and the area used in the dry season was significantly larger than that of the wet season. the smallest distance travelled by group was 480 m/day in may and the longest was 1,980 m/day in march, but with no significant differences between seasons. the total home range used fo ...200010959111
characterization of constitutive heterochromatin of callithrix geoffroyi (callitrichidae, primates) by restriction enzymes and fluorochrome bands.the neotropical primate genus callithrix comprises two groups of species, jacchus and argentata, which inhabit distinct geographical regions and manifest different fur coloration and constitutive heterochromatin (ch) markers in their karyotypes. in this investigation the ch of a representative of the jacchus group, callithrix geoffroyi, was analysed using fluorochromes and restriction enzymes in situ. to clarify the source of the constitutive heterochromatin of both groups, the data obtained in ...200010755215
[hybridization of male callithrix geoffroyi (humboldt, k8k2) x female c. jacchus (linneacus, 1758), and artificial growth of the hybrid newborn (callitrichidae, primates)]. 1976828284
high trypanosoma spp. diversity is maintained by bats and triatomines in espírito santo state, brazil.the aim of this study was to reevaluate the ecology of an area in the atlantic forest, southeast brazil, where chagas disease (cd) has been found to occur. in a previous study, immediately after the occurrence of a cd case, we did not observe any sylvatic small mammals or dogs with trypanosoma cruzi cruzi infections, but triatoma vitticeps presented high t. c. cruzi infection rates. in this study, we investigated bats together with non-volant mammals, dogs, and triatomines to explore other possi ...201729176770
a comparative study of litter size and sex composition in a large dataset of callitrichine monkeys.in many birds and mammals, the size and sex composition of litters can have important downstream effects for individual offspring. primates are model organisms for questions of cooperation and conflict, but the factors shaping interactions among same-age siblings have been less-studied in primates because most species bear single young. however, callitrichines (marmosets, tamarins, and lion tamarins) frequently bear litters of two or more, thereby providing the opportunity to ask whether variati ...201931389057
nonhuman primate welfare: can there be a relationship between personality, lateralization and physiological indicators?measuring personality is being used to improved nonhuman primate welfare. to expand its use, it is important to identify traits that are shared between species and that measures are reliable, easy to use and less time consuming. combining personality and other indicators strong validation of the results can be obtained. in the present study, we sought to determine if there is a link between physiological stress response (fecal cortisol metabolites), personality (ratings made by animal keepers an ...201931271769
gum feeder as environmental enrichment for zoo marmosets and tamarins.tamarins and marmosets are small-bodied social callitrichines. wild callitrichines feed on exudates, such as sap and gum; particularly, marmosets are mainly gummivores, while tamarins consume gums only occasionally and opportunistically. zoo marmosets and tamarins are usually provided with gum arabic as an alternative to the exudates normally found in the wild. the aim of this study was to evaluate the effects of a gum feeder on the behavior and well-being of four zoo-managed callitrichines. we ...202031944345
chromosome painting of the red-handed tamarin (saguinus midas) compared to other callitrichinae monkeys.here we present, for the first time, the complete chromosome painting map of saguinus midas, the red-handed tamarin. chromosome banding and painting with human chromosome-specific probes were used to compare the karyotype of this species with those of four other neotropical primates of the subfamily callitrichinae: leontopithecus rosalia, callithrix geoffroyi, c. penicillata, and mico argentatus. the chromosome painting map of s. midas was identical to that of l. rosalia and other previously stu ...201830222938
feeding behavior of geoffroy's marmoset (callithrix geoffroyi) in an atlantic forest fragment of south-eastern brazil.we report on the diet and feeding behaviour of a group of geoffroy's marmosets (callithrix geoffroyi) in an atlantic forest fragment in south-eastern brazil, studied during the period february 1993 to januaray 1994. major food categories were gums (68.6%) fruits (15%), and small animal prey (invertebrates 14.6% and vertebrates 0.8%). dietary changes were observed between the wet and dry seasons, although they were not statistically significant. insects and gums were consumed throughout the year ...200030545189
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