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1.
Qualitative observations in several European zoos revealed a high proportion of obese individuals in different species of lemurs. This phenomenon was examined in both subspecies of the ruffed lemur (Varecia variegata variegata and Varecia variegata rubra). Data on body weight were obtained from 43 animals in 13 European zoos and were compared with body weights of wild ruffed lemurs. The captive individuals’ mean weight was significantly higher than either of two different samples of wild V. variegata variegata. Using a weight‐based definition of obesity, 46.5% of the individuals in our sample were obese. Neither significant differences in body weight between the two subspecies nor between sexes could be found. Body weight did not correlate with age. The findings are discussed with reference to the feeding ecology of ruffed lemurs and their nutrition in captivity and to implications for captive breeding programs for this species. Zoo Biol 20:261–269, 2001. © 2001 Wiley‐Liss, Inc.  相似文献   

2.
This study presents the first detailed morphometric measurements of wild caught black-and-white ruffed lemurs (Varecia variegata) from the eastern rainforests of Madagascar and aims to quantify the morphological variation present throughout their recognized range. One hundred and forty-four adult and juvenile individuals from 15 sites were sampled for 20 cranial, dental and postcranial morphometric and body mass measurements. Data were collected from an equal number of male and female individuals sampled across seasons over a 7-year period (1999-2002, 2004-2006). Results indicate that adult body mass and morphometric measurements varied between sexes across sites; however, the only significant intersexual difference found was that females possessed, on average, longer tails than males. Contrary to previous studies, significant seasonal variation could not be detected in either male or female body mass or testicular volume (i.e., breeding vs. nonbreeding, food-scarce vs. food-abundant seasons). Measurements did, however, vary significantly by site and subspecies, though clinal variation could not explain these differences. The introduced population from Nosy Mangabe exhibited significantly lower body mass and overall body length than all other populations; however, this distinction may not have been attributable to natural variation, and may have instead resulted from the ecologically restrictive habitat (e.g., unusually high lemur population densities, limited food resources, ecological isolation) of this introduced population. Finally, although fore-to-hindlimb, brachium-to-thigh and hindlimb indices were comparable to previous values, forelimb indices calculated here deviate significantly from previous reports, placing V. variegata within the upper range of lemurid taxa. It is currently unknown whether this is an artifact of sampling methods (i.e., live vs. skeletal specimens) or whether this is an avenue that warrants further investigation.  相似文献   

3.
During a 3 month field study, 18 group encounters between four groups of Alaotran gentle lemurs (Hapalemur griseus alaotrensis) were observed in the Lake Alaotra marshland in Madagascar. Behaviors observed during group encounters are described, and quantitative data on intergroup interactions and ranging patterns are discussed in the context of territoriality. Intergroup interactions varied in their intensity, ranging from visual monitoring, scent marking, and display locomotion to penetrating the neighboring range. A quarter (27%) of the encounters were aggressive, involving chases and confrontation displays, and no affiliative interactions were observed. Both adult males and females were involved in intergroup encounters, with males playing more active roles. All encounters took place in the small overlapping areas of neighboring home ranges. The outcome of an aggressive encounter was determined by its location, with the resident group always driving out the intruding one. The Alaotran gentle lemur actively advertised and consistently defended a large area of its home range against intrusion of neighboring groups and can therefore be considered territorial. Am. J. Primatol. 46:251–258, 1998. © 1998 Wiley-Liss, Inc.  相似文献   

4.
The growing interest in many zoos, wildlife parks and game ranches in the captive breeding of wild species has brought about much interest and research in developing and testing artificial methods of breeding. Much of this work has been concentrated in endangered species. The author outlines the relevance and utilization of such techniques and reviews successful attempts in this area and elaborates on future potential ones. A brief review is given of successful artificial methods of breeding domestic species and how this may be applied to non-domestic ones. Areas that are covered are semen collection, semen freezing, induction of estrus, artificial insemination, embryo transfer including interspecies transfer and embryo surgery. It is acknowledged that it is highly unlikely that an artificial program could save a species from extinction but such methods could greatly assist a comprehensive natural breeding program.  相似文献   

5.
A comparative study has been made of the major lipid fractions and their fatty acid compositions in the yolk of eggs from ostriches under wild and farmed conditions. There were no differences in the lipid contents and proportions of the lipid fractions between the two groups of yolks. In both groups of yolks triacylglycerol and phospholipid were the major fractions. In the eggs from the wild ostriches, all the lipid fractions displayed substantial concentrations of C18 polyunsaturated fatty acids, triacylglycerol being particularly rich in linolenic acid and phospholipid rich in linoleic acid; phospholipid displayed substantial concentrations also of C20 and C22 polyunsaturates. There were considerable differences in the fatty acid compositions between the yolks. Those from the farmed birds displayed lower proportions of C18 polyunsaturates, particularly linolenic acid, throughout the lipid fractions. Compensatory increases were displayed most obviously in the concentrations of oleic acid and palmitoleic acid as well as other acids. The distinctive and extensive changes in fatty acid composition, particularly relating to the polyunsaturates, are discussed with respect to overall dietary requirements and specificities for embryo metabolism and possible effects on reproductive performance.  相似文献   

6.
We investigated the effects of cognitive experiments by direct comparison of activity budgets between wild and captive chimpanzees. One goal of captive management is to ensure that the activity budgets of captive animals are as similar as possible to those of their wild counterparts. However, such similarity has rarely been achieved. We compared the activity budget among three groups of chimpanzees: wild chimpanzees in Bossou (Guinea, n = 10), and captive chimpanzees who participated in cognitive experiments (experimental chimpanzees, n = 6) or did not participate in the experiments (nonexperimental chimpanzees, n = 6) at the Primate Research Institute (Japan). The experimental chimpanzees voluntarily participated in computer‐controlled cognitive tasks and small pieces of fruits were provided as rewards. The data from captivity were obtained on the experimental days (weekdays) and nonexperimental days (weekends). In both study sites, we followed each chimpanzee from about 7 a.m. until the time when chimpanzees started to rest in the evening. The behaviors were recorded every 1 min. The results showed that on weekdays, feeding time and resting time of the experimental chimpanzees were almost the same as those of wild chimpanzees. However, for the nonexperimental chimpanzees, feeding time was significantly shorter and resting time was longer than those of the wild chimpanzees. In contrast, no difference was found in feeding time or resting time of the two groups of captive chimpanzees on weekends. The results suggested that the cognitive experiments worked as an efficient method for food‐based enrichment. Am. J. Primatol. 73:1231–1238, 2011. © 2011 Wiley Periodicals, Inc.  相似文献   

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This study explores the relations between captive and noncaptive (literature-reported wild) adult weights in 53 anthropoid primate species. Based on recent studies of variation in growth among wild populations, it is expected that captive and wild weights are highly correlated. In addition, the lack of a relation between species size and captive and wild weights is anticipated. Differences between wild and captive weights are investigated. Correlations between captive and wild weights are high. Within groups of closely related species, correlations can be expected to average r = .95 for both males and females. At low taxonomic levels (within genera), correlations are not generally as high. However, captive and noncaptive intrageneric correlations are comparable to intrageneric correlations based solely on wild weights reported by different literature sources. Size appears to be unrelated to differences in captive and wild weights. Species that appear to be at elevated risk of obesity are identified. This analysis finds that deviations between captive and wild weights are positively related to growth duration (measured for captive primates). This finding implies that, in long-growing species, wild weights may underestimate asymptotic size. Hypotheses explaining this phenomenon are developed. In general, extensive overlap in weight between samples of captive and wild primates is documented. © 1994 Wiley-Liss, Inc.  相似文献   

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10.
Captive breeding of rare and endangered prosimians may be enhanced by an increased understanding of all aspects of their seasonal mating behavior. In this study, the agonistic and grooming behaior of captiveL. coronatus were studied during their annual breeding season. Between October and March, selected aspects of agonistic and grooming behavior of four male-female groups were recorded. Males initiated significantly more allogrooming than females. The frequency of this behavior pattern increased significantly in the weeks of estrus. Females performed significantly more agonistic behavior patterns than males. The mean frequency of agonistic interactions decreased significantly during the breeding season. In successfully reproducing groups males showed much less agonism towards females, than they did in unsuccessful groups. Inter-specific comparisons demonstrated that the patterns of agonistic interactions during the breeding season are very different among closely related species of lemurids. The conclusions drawn from this study are that captive breeding of crowned lemurs may be enhanced by keeping permanent multi-male, multi-female groups.  相似文献   

11.
To provide information for managing the captive population of endangered Guam Micronesian kingfishers (Halcyon cinnamomina cinnamomina), four biologically relevant thermal metrics were compared among captive facilities on the United States mainland and habitats used by wild Micronesian kingfishers on the island of Pohnpei (H. c. reichenbachii), Federated States of Micronesia. Additionally, aviaries where kingfishers laid eggs were compared to those in which birds did not attempt to breed. Compared to aviaries, habitats used by wild Pohnpei kingfishers had 3.2°C higher daily maximum and minimum temperatures and the proportion of time when temperatures were in the birds' thermoneutral zone was 45% greater. No differences were found in the magnitude of temperature fluctuation in captive and wild environments. In captive environments in which birds bred, daily maximum temperatures were 2.1°C higher and temperatures were within the thermoneutral zone 25% more often than in the aviaries where the kingfishers did not breed. No differences were found in the magnitude of temperature fluctuation or the daily minimum temperature. Results suggest that the thermal environment has the potential to influence reproduction, and that consideration should be given to increasing temperatures in captive breeding facilities to improve propagation of the endangered Micronesian kingfisher. Zoo Biol 23:301–308, 2004. Published 2004 Wiley‐Liss, Inc.  相似文献   

12.
Against a background of poor breeding success and cub survival in captive cheetahs, a knowledge of the early maternal behavior in the wild may yield useful information for comparison with the captive situation. This paper documents the types of lair sites used by mothers to conceal their newborn cubs in the wild situation, and details patterns of maternal behavior observed during this period. Four kinds of lairs were used by cheetah mothers, and the amount of protection from the elements and predators was assessed for each. Lair type appeared to have little effect on cub survival. Cubs were concealed in lairs for 8.2 weeks on average, although larger litters tended to leave lairs earlier. During this period, cubs were moved to new lairs approximately every 5.6 days. Cubs were left for an average of 9.6 hours while their mothers went hunting, but mothers virtually always returned to them around nightfall, even if they failed to catch any prey. Maternal neglect and cub abandonment, which account for many cub deaths in captivity, are abnormal in the wild, except when prey is very scarce. Improved husbandry techniques, such as the provision of multiple, secluded nest boxes, and remote monitoring conditions should promote breeding success in captivity. In addition, noise and human disturbance should be minimized.  相似文献   

13.
Captive breeding is a high profile management tool used for conserving threatened species. However, the inevitable consequence of generations in captivity is broad scale and often-rapid phenotypic divergence between captive and wild individuals, through environmental differences and genetic processes. Although poorly understood, mate choice preference is one of the changes that may occur in captivity that could have important implications for the reintroduction success of captive-bred animals. We bred wild-caught house mice for three generations to examine mating patterns and reproductive outcomes when these animals were simultaneously released into multiple outdoor enclosures with wild conspecifics. At release, there were significant differences in phenotypic (e.g. body mass) and genetic measures (e.g. Gst and F) between captive-bred and wild adult mice. Furthermore, 83% of offspring produced post-release were of same source parentage, inferring pronounced assortative mating. Our findings suggest that captive breeding may affect mating preferences, with potentially adverse implications for the success of threatened species reintroduction programmes.  相似文献   

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16.
Supplementation of wild populations with captive-bred organisms is a common practice for conservation of threatened wild populations. Yet it is largely unknown whether such programmes actually help population size recovery. While a negative genetic effect of captive breeding that decreases fitness of captive-bred organisms has been detected, there is no direct evidence for a carry-over effect of captive breeding in their wild-born descendants, which would drag down the fitness of the wild population in subsequent generations. In this study, we use genetic parentage assignments to reconstruct a pedigree and estimate reproductive fitness of the wild-born descendants of captive-bred parents in a supplemented population of steelhead trout (Oncorhynchus mykiss). The estimated fitness varied among years, but overall relative reproductive fitness was only 37 per cent in wild-born fish from two captive-bred parents and 87 per cent in those from one captive-bred and one wild parent (relative to those from two wild parents). Our results suggest a significant carry-over effect of captive breeding, which has negative influence on the size of the wild population in the generation after supplementation. In this population, the population fitness could have been 8 per cent higher if there was no carry-over effect during the study period.  相似文献   

17.
Methods for the identification of the sex of bird species without external sexual dimorphism are specially important in field studies and for captive breeding of endangered taxa. We confirmed the accuracy of a polymerase chain reaction (PCR)-based method to identify the sex in three disparate avian orders that included 31 species of parrot, two species of toucan, and eight species of curassow, for which many individuals were previously sexed. In each case, two DNA fragments were amplified in females and one in males with the use of a single set of primers. This method was also tested on unsexed birds of 13 other species of parrot and five species of toucan. The same kind of polymorphism was detected in each. The PCR products of parrots and toucans could be separated in simple agarose gels, while the curassows' products could only be distinguished in acrylamide gels. An advantage of this DNA test is that samples of blood or feathers can be easily collected and stored at room temperature, which is of particular importance for studies of wild birds. Zoo Biol 17:415–423, 1998. © 1998 Wiley-Liss, Inc.  相似文献   

18.
A captive group of Japanese macaques (Macaca fuscata). consisting of one adult male and three adult females, was observed for 88 hr during the 1988 mating season. We focused on the group's sexual activities because understanding how social dynamics affect reproductive behavior may enhance our ability to establish self-sustaining captive populations. The adult male exhibited distinct preferences in copulation partners, although all females were receptive and cycled during the study period. The dominant female participated in the most copulations and successfully harassed and disrupted copulations between the male and the other females. The alpha female, therefore, actively constrained the formation of mating pairs. Further, the male did not consort with his year-round female grooming partner. This female, the least dominant member of the group, engaged in the most autosexual and homosexual behavior. Birth season data show that only the dominant female bore offspring. This study emphasizes the influence of social dynamics on a group's reproductive potential and suggests an alternative means by which females can influence consort formation.  相似文献   

19.
Ten male and nine female habituated chimpanzees (Pan troglodytes schweinfurthii) in the Kasoje area of the Mahale Mountains National Park, Tanzania, were weighed intermittently between December 1973 and March 1980 by luring them up a rope hung on a spring balance: six adult males averaged 42.0 kg and eight adult females 35.2 kg. Seasonal change in body weight was recognized at least partially; body weights tended to decrease in the later part of the wet season presumably because of food shortage in the middle of the wet season. Comparison of body weight among three populations of the same subspecies suggests that adult female chimpanzees of Mahale appear to be heavier than those of the Gombe National Park, Tanzania, and that they seem to be similar to the forest-living counterparts of eastern Zaire. On the other hand, body weights of adult male chimpanzees from the three populations do not show significant differences. Perhaps feeding competition among adult females in a small, isolated habitat is more severe than that among adult males, which may result in the body weight reduction among adult female chimpanzees at Gombe.  相似文献   

20.
Data from 25 male and 44 female free-ranging dusky leaf monkeys, Presbytis obscura,are analyzed. In a male the mean total testicular weight, 5.82 g, represents 0.078% of the mean adult body weight, 7.39 kg. The mean total ovarian weight, 0.52 g, represents 0.008% of the mean female adult body weight, 6.47 kg. A moderate degree of sexual dimorphism thus exists in this species, female body weight representing 88% that of the male. No seasonal variation in the adult body weight or total gonadal weight of either sex occurs. Only in males is there a strong positive correlation between left and right gonadal weight, and no correlation exists between the total gonadal weight and the estimated age of either male or female adults. Among adults, only females evince a significant positive correlation between total gonadal weight and body weight. No marked change in total ovarian weight occurs during the menstrual cycle, pregnancy, or lactation.  相似文献   

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