Showing papers on "Primate published in 1985"

Habitat preferences, diet, feeding strategy and social organization of the black spider monkey (Ateles paniscus paniscus Linnaeus 1758) in Surinam

Abstract: A Socioecological Field Study. This monograph reports on a 26 month socioecological study of black spider monkeys (Ateles paniscus paniscus)in the Raleigh-vallen — Voltzberg Nature Reserve, Surinam. It recognizes the fundamental importance of food to the behavior and the regulation of population density fox this primate. It clarifies the complex temporal and spatial effects of tropical rain forest food sources on the behavior of a group of spider monkeys, concentrating on food category, food plant identity and phenology, and quantity, density and dispersion of the most important food sources. In addition, the present study describes habitat choice, optimal feeding strategy and sexual behavior of the spider monkey, and discusses implications of diet for social behavior. This study is also fundamental to conservation. Specialized in eating mature fruits, the spider monkey is a very important dispersal agent for many trees and lianes, particularly canopy species. However, the spider monkey is probably the most vulnerable monkey species in Surinam and it is disappearing rapidly throughout the remainder of its range. Unfortunately, it is large and noisy and can be easily tracked and hunted. It is largely restricted to undisturbed high forest, and consequently habitat destruction has more effect on it than on most other species. Together with its slow reproductive rate (a female gives birth only once every four or five years), this means that the species is poorly adapted to recover from exploitation. In order to implement proper measures for conservation, data on forest type preferences, diet and social behavior of the species, or on closely related species, in undisturbed areas, such as the one described in this monograph, are essential tools for assessing the potential of proposed protected areas.

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 Endocrine System of the Squirrel Monkey

Abstract: In 1968, when the first treatise on the squirrel monkey appeared, it was already apparent that the physiology of New World monkeys differed from that of Old World primates, but few investigators were aware of the extensive differences in hormone metabolism and secretion (Rosenblum and Cooper, 1968). Since that time, it has become increasingly evident that the endocrine system of New World monkeys is extremely divergent from the general primate pattern in terms of both absolute hormone levels and the synthetic pathways utilized. We now know that most of the Callithricidae and smaller Cebidae have unusually high levels of adrenal and gonadal hormones, although typical values are difficult to describe because of the remarkable diversity in their reproductive physiology [for a species comparison, see Hearn (1983)]. In this chapter we will review a series of recent studies on the endocrine system of the squirrel monkey, which has some of the highest hormone levels observed so far. The level and magnitude of the hormone responses in the squirrel monkey have also provided a unique opportunity for assessing the influence of psychological and environmental variables, which may exert less overt effects in species with lower hormone levels. We will discuss the influence of seasonal and diurnal rhythms and the effect of genetic and maturational variables, and finally consider several of the important psychological processes that affect endocrine function.

Reliability of the emotions profile index, primate form, withPapio hamadryas, Macaca fuscata, and twoSaimiri species

Abstract: An evaluation of the reliability of the Emotions Profile Index (EPI), primate form, was carried out using two captive species of Old World monkeys (Papio hamadryas andMacaca fuscata) and two species (?) of New World monkeys (Saimiri sciureus andS. boliviensis). Observers, some familiar with the animals and some unfamiliar, rated members of the four groups at different times. Inter-rater reliability was high for most members of all species, but only when the observers were familiar with the animals. Assessments remained stable over at least one year.

Light effects on circadian timing system of a diurnal primate, the squirrel monkey.

Abstract: We examined light effects on the circadian timing system of the squirrel monkey. A phase-response curve to 1-h pulses of light was constructed for the drinking rhythm of six animals. The phase-response curve was the same type as that exhibited by nocturnal rodents, with phase delays occurring early in the subjective night and phase advances late in the subjective night. The range of entrainment of 10 monkeys to days with 1 h light and x h dark was determined. Five monkeys used to generate the phase-response curve were also used in the range of entrainment determination. For short light-dark cycles the range of entrainment was smaller than that expected, with no monkey entraining to a day length of less than 23.5 h.

The Role of Prolactin in the Regulation of the Primate Corpus Luteum

Abstract: The role of PRL in the control of corpus luteum (CL) function was examined in hyperprolactinemic and euprolactinemic female rhesus monkeys with hypothalamic lesions in which ovulatory menstrual cycles were induced by the pulsatile administration of GnRH, in intact postpartum monkeys nursing their infants, as well as in animals treated with bromocriptine. In the lesioned monkeys, neither markedly elevated nor undetectable (bromocriptine-suppressed) PRL levels influenced the time courses of postovulatory plasma progesterone concentrations compared to those in monkeys with normal PRL concentrations. Plasma progesterone concentrations in the hyperprolactinemic monkeys, however, did not decline to undetectable levels at the end of the luteal phase, as is the case in normal animals, but remained slightly elevated for extended periods, a pattern characteristic of lactating animals. In both lesioned and postpartum animals, bromocriptine administration or removal of suckling infants from the latter resulted in com...

Gait characteristics of two squirrel monkeys, with emphasis on relationships with speed and neural control

Abstract: Two adult squirrel monkeys (one of each sex) were trained to locomote on a motor-driven treadmill at seven fixed speeds within 0.89–2.58 m/second. Subsequently, the animals were filmed while locomoting at these speeds, with the films then being used to determine gait parameters. The female monkey exhibited lateral-sequence symmetrical gaits at slow speeds, and transverse and rotatory gallops at fast speeds. The male used lateral-sequence symmetrical gaits at all speeds. The squirrel monkeys exhibited typical relationships between temporal gait parameters and increased speed, with these relationships continuing across the run-gallop transition. An analysis-of footfall intervals (delays) and support patterns indicated that during symmetrical gaits these monkeys emphasized lateral support. During galloping, one delay, the trailing hindlimb to trailing forelimb, was found to be very stable, both across speeds and for both types of galloping. Also during galloping, swing duration was found to be more variable than stance duration. These findings are interpreted with regard to understanding the neural control of locomotion in tetrapods, and more specifically, in primates. The latter part of this discussion revolves around three basic differences between primate and non primate gaits: (1) utilization of diagonal-sequence gaits by primates (although the squirrel monkeys were atypical in this regard); (2) absence of a running trot in primates; and (3) absence of stepping following spinal cord transection in primates. These three differences reflect greater supraspinal control of locomotion in primates, and possibly intrinsic differences in the coupling of spinal locomotor generators.

Loa loa: development and course of patency in experimentally-infected primates.

Abstract: Loa loa infections were studied in baboons, rhesus and patas monkeys. Animals were infected either by s.c. injection of third-stage larvae (L 3) or by surgical implantation of juvenile worms of known age, sex and number. Microfilaremia was first detected in baboons at 140 days following inoculation of L 3 and at 142 days and 143 days in patas and rhesus monkeys, respectively; the mean prepatent period was 151 days in baboons, 149 days in patas monkeys and 169 days in rhesus monkeys. The primary wave of microfilariae (mf) was suppressed by the spleen in all three primate species. In baboons, the initial wave of mf lasted from 11 to 46 weeks (mean: 22 weeks), whereas in patas monkeys it persisted for 47 to 60 weeks, and in rhesus monkeys for 1 to 2 years. Gross and microscopical changes in the spleen were noted in all three primate species and consisted of numerous granulomata in the red pulp underlying the capsule. A resurgence of mf was observed following splenectomy in all three species of monkeys. Postsplenectomy levels of microfilaremia typically exceeded presplenectomy levels. One pair of worms was sufficient to produce patent infections in monkeys for extended periods of time. However, levels of microfilaremia were lower than in monkeys which received 75 and 200 to 300 L 3, although some overlap in microfilaremias between groups did occur. Overall, there was no proportional relationship between levels of microfilaremia and numbers of adult worms recovered from monkeys at necropsy. It was observed that, in the primate host, Loa is a long-lived parasite. Living worms were recovered from the tissues as long as 9 years after inoculation and there was no reason to doubt that patency would have persisted for some time into the future. Adult worms were frequently observed moving freely in the subcutaneous tissues of the primate hosts, although no instance of Calabar swellings or the presence of worms in or around the eye were ever recorded. The primate model of loiasis is an especially useful system because of the predictability of the behavior of the parasite. In most regards, the behavior of L. loa in the primate host is comparable to observations on the parasi e in man.(ABSTRACT TRUNCATED AT 400 WORDS)

Meat eating and predation in captive‐born semi‐free‐ranging Lemur fulvus and caged Lemur macaco

Abstract: A group of brown lemurs, Lemur fulvus, and a group of black lemurs, Lemur macaco, at the Duke University Center for the Study of Primate Biology and History have been observed to capture and eat birds and lizards. Although vertebrate prey are not unusual for many carnivorous prosimians, folivorous prosimians never have been observed to take vertebrates in the wild and rarely even insects.

Effects of Surrogate-Rearing on the Infant Squirrel Monkey

Abstract: At the time of this book’s preceding companion volume, there were no pubished accounts of surrogate-rearing in the squirrel monkey. However, in the intervening years, this situation has changed dramatically. Young Saimiri have been raised on maternal surrogates in a number of laboratories, and more is now known about the effects of surrogate-rearing in this primate species than in any other, with the exception of the rhesus macaque. Most of the work with surrogate-reared Saimiri has focused on the infant’s responsiveness and emotional attachment to its rearing figure. In addition, a substantial amount of effort has been directed at understanding the general behavior development of these animals.

Disseminated nocardiosis in three macaque monkeys

Abstract: Extrapulmonary nocardiosis was diagnosed at necropsy in two rhesus monkeys (Macaca mulatta) and one pigtailed monkey (M. nemestrina) over a four-year period in a large primate center. Typical lesions were multiple pyogranulomatous foci in the liver, intestines, peritoneum, lung and brain. Partially acid-fast, branching, filamentous organisms were seen in all lesions. Nocardia sp. was isolated from two cases. We postulate that two of the monkeys were infected by the oral route because of the distribution of lesions.

The social structure of primates

Abstract: A comprehensive comparative study of the social structure of primates revealed: There is no social structure which can be considered typical and discriminative for primates. The varying social structures of the extant primate genera cannot be derived from each other: In contrast it seems that the basic, ancestral condition was that of solitary living animals, loosely aggregated. It can be assumed that the development to a gregarious society took place in two entirely different ways. In terms of primate phylogeny this different development can be shown for the prosimians as well as for the old world and new world monkeys as independently occurring processes. One way of behavioral specialization resulted in close pair bonds or in small family groups, whereas the other led to female groups. The presupposition for the forming of a society based on female groups is the close contact between the individuals and in addition to this, a remarkable social tolerance of females to each other. Social specializations which can be considered transitional from the basic condition are frequently found in prosimians. The kinds of social structures of the particular genera are in close relation to their taxonomic positions in the phylogenetic scala. The number of males in larger social groups of primates is substantially irrelevant as the groups are socially most dependent on the females. The protecting males are socially peripheral. The social units of most of the primate species are matrilocal and endure for several generations. In contrast, the social units of the gibbons and of the pongids are patrilocal and are established anew by the females in each generation. Consequently the social unit disintegrates on the death of the male. In all genera studied, male and female individuals present considerable behavioral differences which can be found even in juveniles. Primates are able to discriminate well known and confident individuals from other less confident; they prefer more confident individuals to less confident ones, and less confident to non-confident. As a consequence of this discriminative ability there is a clear preference for near when compared to distant relatives. The complexity of the social relations is brought about by this ability to discriminate combined with the longevity of primates. This is a characteristic and discriminative feature of the primate order. Dominance relations occur in every social group of primates. Linear hierarchies of dominance have been developed only once in prosimians (Lemur) and also once in simians (Cercopithecinae). Therefore, liner hierarchies are not typical for primates.

Hormones and the Sexual Behaviour of Monkeys

Abstract: The sexual behaviour of monkeys is very different from that of non-primate species in that it is, to a large extent, emancipated from gonadal control. Female monkeys when paired daily in the laboratory with the male do not show true periodic oestrous behaviour but are prepared to receive the male throughout their menstrual cycle (Michael and Welegalla 1968), and for long periods even following ovariectomy (Michael and Zumpe 1970). Indeed, female solicitations to the males, an index of their willingness to mate, increase after ovariectomy (Zumpe and Michael 1970), a finding in marked contrast to many rodent species. Sexual interactions with the male do, however, vary during the menstrual cycle, being more frequent in the follicular phase especially around mid-cycle for a number of primate species (Talapoin — Scruton and Herbert 1970; Patas monkey — Rowell and Hartwell 1978; Pigtail macaque — Tokuda et al. 1968; Eaton and Resko 1974; Chacma baboon — Saayman 1970; Gelada baboon — Dunbar 1978; Gorilla — Nadler 1975a; Chimpanzee — Tutin 1980; Macaca fascicularis — Zumpe and Michael 1983). Paradoxically, the females solicitations to the male may be very low at this time, and most of the changes in sexual interactions in relationship to the menstrual cycle can be accounted for by changes in female attractiveness (Keverne 1976).

Endogenous development of Eimeria nieschulzi: fourth generation merogony.

Abstract: on only 2 occasions with rates of 5 and 16 percent. No attempts were made to further passage the infection. After being treated with chloroquine (30 mg base over 2 days), the animals were followed for approximately 100 days; no relapses of the infection were observed. These transmissions by the bites of infected An. dirus mosquitoes indicate that splenectomized A. a. boliviensis monkeys are susceptible to infection with the RO strain of P. cynomolgi. In rhesus monkeys, the mean prepatent period has been reported as 9.8 days with a range of 7 to 17 days (Coatney et al., 1971. The primate malarias. U.S. Government Printing Office, 366 p.). The present range of 12 to 19 days with a mean of 15.8 days appears to be longer than that of the rhesus monkeys but somewhat shorter than the 12 to 30 days (mean of 18.2 days) previously reported for the Colombian Aotus (Collins et al., 1975, loc. cit.). All of the animals used in the present study had previously been infected with other species of Plasmodium. Thus, the present study indicates that such animals are not "lost" for additional work, but can be used for studies which require cyclic transmission with P. cynomolgi. Since P. cynomolgi in rhesus monkeys is characterized by frequent and multiple relapses, it would appear that infections in these A. a. boliviensis monkeys were altered with regard to relapse potential. The reasons for this are not readily apparent. Considering the high cost of obtaining and housing the larger Old World macaques for malarial studies, consideration could be given to the use of these smaller Bolivian Aotus monkeys for a number of studies with P. cynomolgi.