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1.
Epidemiological studies were conducted in the Lake Langano area in the Rift Valley of Ethiopia to determine the occurrence of schistosomiasis and assess factors involved in its transmission. Microscopic examination of faecal specimens from free ranging Papio anubis (anubis baboon) troops from Bishan Gari and Burka Dita forest reserves revealed Schistosoma mansoni eggs with a prevalence of 12.1% (11/91) and 26.2%(34/130), respectively. The eggs were viable as confirmed by miracidial hatching and infectivity tests. Out of the total 12 communities (three schools, five villages and one herdsmen community) surveyed for schistosomiasis around Lake Langano, individuals excreting S. mansoni eggs were found in nine communities with prevalence of infection ranging from 1.4 to 43%. The intensity of infection ranged from 24 EPG (eggs per gram of faeces) to 243 EPG. Excretion of viable eggs by the baboons indicate that they play a role in maintenance of S. mansoni infection in the locality. The detection of S. mansoni eggs in young children, collection of cercarial-infected Biomphalaria pfeifferi in water bodies, and establishment of S. mansoni infection in lab-bred mice have confirmed establishment of transmission foci in Kime area, south-east of Lake Langano. However, the lake itself does not seem to support transmission of schistosomiasis since no snails were found along the shore of the Lake. Further investigations are indicated to fully elucidate the role baboons play in the epidemiology of schistosomiasis in the Rift Valley of Ethiopia. The risk of introduction of water-based development projects in these new endemic foci in relation to S. mansoni infection in the baboons is discussed.  相似文献   

2.
A nonsurgical embryo recovery procedure, developed to allow the economical acquisition of cleavage stage baboon embryos, has been successfully used for 4 years. With this technique, 498 eggs have been recovered from 979 uterine flushes (50.9%) on 71 baboons. Of 467 eggs recovered from mated baboons, 290 (62.1%) were fertilized. Papio anubis females provided a higher percentage of fertilized eggs (75.3%) than did Papio hamadryas (47.8%) or Papio cynocephalus (44.3%) females following exposure to males during estrus, although sexual preference may be responsible for the reduced fertilization rate in the P. cynocephalus females. Recovery rates from individual baboons ranged from 0% (n = 11) to between 66% and 93% for ten baboons from each of which 12–33 eggs have been recovered. Fertilized eggs were at the two-cell (n = 23) to blastocyst (n = 53) stage at recovery 1–6 days postdeturgescence (PD) of the sex skin, with morulae (n = 84) being the most frequent cell stage recovered (30%). The optimum time for performing the procedure was the third day PD, when 113 (40%) embryos were recovered. The abilities of baboons to become pregnant and to provide fertilized embryos were significantly related (P < 0.005), allowing the embryo recovery technique to be used as a screening procedure for evaluating baboon fertility.  相似文献   

3.
This paper reports a study designed to test the hypothesis that a relationship exists among dominance rank, tension, and scratch behaviors in anubis baboons (Papio cynocephalus anubis). Our study was conducted on two groups of male baboons, each containing eight unrelated individuals who were approximately 6 years of age and who shared common rearing histories. Focal animal sampling was used to collect behavioral data. Hand scratching, foot scratching, avoid, tension, allogrooming, autogrooming, and manipulation were measured as acts performed per hour of sampling. Dominance matrices were constructed based on net difference of avoid behavior performed and received (adjusted for time sampled). Individual status ranks were grouped into two status classes, high and low. Analysis of variance models demonstrated significant differences in the performance rate of scratching behaviors by dominance rank class, as well as differences in scratching performance by tension class. Individuals in the high status class had significantly higher rates of total scratching, hand scratching, foot scratching, and tension behavior performance than their counterparts in the low status class. No significant difference was found between status classes or tension classes for performance rate of allogrooming, autogrooming, or manipulation behavior. The frequency of scratching and general level of activity were not significantly correlated. The results are interpreted to indicate the possibility that scratching may function as a displacement behavior, which subjectively appears to communicate heightened frustration, anxiety, or arousal.  相似文献   

4.
At least three diurnal primate taxa are still present in Eritrea, NE Africa: hamadryas baboons (Papio hamadryas hamadryas), olive baboons (Papio h. anubis) and grivet monkeys (Chlorocebus aethiops aethiops). However, information on status and distribution of primates and their habitats in Eritrea is outdated and incomplete. We conducted a primate survey, focussing on hamadryas baboons, to obtain data which will be integrated in a national wildlife management and conservation plan in Eritrea. We obtained information about the geographical distribution and abundance of baboons, their altitudinal range, habitat quality of their home-ranges, aggregation sizes at sleeping cliffs and predator presence. We described habitat quality via the Normalized Difference Vegetation Index (NDVI), a vegetation classification of Landsat MSS satellite data. Hamadryas and olive baboons are still present in Eritrea in ample numbers. Their geographical distributions in 1997 and 1998 did not deviate significantly from their historical distributions. An estimated 15,000 Papio hamadryas hamadryas lived in the 25,000-km2 area of survey (0.58 baboons/km2). Population densities of hamadryas baboons in many parts of the survey area are higher than at Kummer's (1968) study site in Ethiopia. Hamadryas baboons live at all altitudes in four of five ecogeographical zones of Eritrea. Olive baboons replaced them in the western lowlands. Both baboon taxa tend to select better quality habitats, characterized by a higher normalized difference vegetation index (NDVI) than the average for the respective ecogeographical zones. Hamadryas baboons show a greater ecological plasticity than olive baboons, which are confined to riverbeds with extended gallery forest. By the end of 1999, a hybrid zone could not be confirmed.  相似文献   

5.
The pattern of excretion of urinary steroid metabolites in the olive baboon (Papio anubis) was examined during the menstrual cycle and in conception cycles in which embryos were surgically removed at intervals between day 11 and day 21 (day 0 = day of preovulatory estrogen peak). Conjugated estrone and pregnanediol-3α-glucuronide were measured in overnight urine samples by direct, nonextraction assays, and the levels were indexed by creatinine. Results showed that measurement of urinary conjugated estrone reflected preovulatory estrogen output and that pregnanediol-3α-glucuronide was an abundant urinary metabolite of progesterone. There was a defined postovulatory increase in the excretion of conjugated estrone during conception cycles in eight of ten animals. The timing of the increase ranged between day 13 and day 19 and was related to the appearance of elevated levels of urinary gonadotrophin. In four animals, increased estrogen excretion was first detected after the day of embryo removal, but this was most likely a response to chorionic gonadotrophin secreted before surgery. The findings demonstrate that measurement of conjugated estrone offers a rapid and practical approach for monitoring ovulation and implantation in the baboon by a single assay technique.  相似文献   

6.
    
Male variation in testosterone (T) levels may, in part, reflect a differential behavioral allocation to mating and parenting effort. This research tests whether demographic indicators of pair bonding and parenting were associated with salivary T levels among Kenyan Swahili men. Men in the sample were either unmarried (N = 17), monogamously married (N = 57), or polygynously married (N = 14), and between ages 29-52. In contrast with earlier findings among North American men, monogamously married men did not have lower T levels than unmarried men. However, among all married men, men with younger genetic children tended to have marginally lower T levels. Polygynously married men, all of whom had two wives, had higher T levels than all other Swahili men. Possible explanations of higher T levels among polygynously married men are explored.  相似文献   

7.
    
We take advantage of an array of hybrid baboons (Papio anubis x Papio hamadryas) living in the same social group to explore the causes and consequences of different male mating strategies. Male hamadryas hold one-male units and exhibit a sustained, intense interest in adult females, regardless of the latter's reproductive state. Anubis baboons, by contrast, live in multi-male, multi-female groups where males compete for females only when the latter are estrous. These two taxa interbreed to form a hybrid zone in the Awash National Park, Ethiopia, where previous work has suggested that hybrid males have intermediate and ineffective behavior. Here, we first examine male mating strategies with respect to morphological and genetic measures of ancestry. We found significant relationships between behavioral measures and morphology; males with more hamadryas-like morphology had more hamadryas-like behavior. However, genetic ancestry was not related to behavior, and in both cases intermediates displayed a previously unreported level of behavioral variation. Furthermore, male behavior was unrelated to natal group. Second, we evaluated reproductive success by microsatellite-based paternity testing. The highest reproductive success was found for individuals exhibiting intermediate behaviors. Moreover, over nine years, some genetically and morphologically intermediate males had high reproductive success. We conclude that the behavior of hybrid males is therefore unlikely to be an absolute barrier to admixture in the region.  相似文献   

8.
Wild male olive baboons (Papio anubis) used females and infants as agonistic buffers. Male residency status determined whether a male used females or whether they were used against him. The success of the strategy depended on the cooperation of the female and the context of the interaction. Female cooperation correlated with preexisting social affiliation with the male user. Male choice of female or infant buffers represented a compromise between the potential effectiveness of each in different situations and the social and spatial availability of females and infants. Nonreproductive social relationships may provide long-term strategic benefits to the individuals who invest in them.  相似文献   

9.
    
We examined the pattern and possible functions of social interactions between adult males and immatures in three free-ranging, multi-male groups of mountain gorillas (Gorilla beringei beringei). Previous studies conducted during the 1970s when groups contained one to three adult males concluded that male-immature relationships were likely to be a form of low-cost paternal investment [Stewart, Mountain gorillas: three decades of research at Karisoke. Cambridge, UK: Cambridge University Press, 2001]. We evaluated whether this hypothesis still held in groups containing six to nine adult males, or if male-immature relationships might serve other functions (e.g. mating effort, kin selection, or alliance building). Overall, we found that immatures spent the most time near, and interacted most with, the alpha silverback. These behaviors peaked during the period when infants were still quite vulnerable but increasing their independence from their mothers. Such findings suggest that parenting effort remains the primary function of male-immature relationships; however, there is some evidence for the mating effort hypothesis as well.  相似文献   

10.
The bipedal behavior of a troop of olive baboons (Papio anubis) is described. Bipedalism is relatively rare but nevertheless occurs in a wide variety of situations, although bipedalism during feeding occurs much more frequently than in other situations. The incidence of bipedalism varies between different age-sex classes and between individuals within age-sex classes. This pattern of bipedalism occurred within an overall adaptive response, particularly in feeding behavior, which was similar to that of the gelada baboon (Theropithecus gelada). The data on bipedalism is used together with an existing model of early hominid differentiation based on T. gelada to indicate the types of bipedal behavior which might have occurred in early hominid small object feeders and to suggest how a bipedal pattern of this type might have served as a basis for the action of selection for a more committedly bipedal pattern at later stages of hominid evolution.  相似文献   

11.
Ken  Inoue 《Plant Species Biology》1990,5(2):197-203
Dichogamy and sex allocation in several populations of Campanula microdonta and C. punctata were investigated with regard to their mating systems. Duration of the staminate phase differed among the populations: staminate phase was longer in self-compatible (SC) and largely outcrossing populations than in self-incompatible (SI) and outcrossing populations or in SC and largely inbreeding populations. Duration of the pistillate phase among the populations was less variable than duration of the staminate phase. Male reproductive effort decreased with increase of the estimated selfing rates. Male allocation (weight ratio of androecium to gynoecium or to total flower) may be used as an indicator of the breeding system. Within each population, small flowers allocate proportionately more resources to the androecium than to the gynoecium. Among populations, SC outcrossing populations tend to produce large ovaries, and SC inbreeding populations tend to produce small ovaries.  相似文献   

12.
BACKGROUND AND METHODS: A total of 284 non-human primate sera were collected between December 2004 and September 2005 and tested by a commercially available dot immunobinding assay for the antibodies to cercopithecine herpesvirus 1, an alphaherpesvirus with high mortality for infected humans. RESULTS: Seropositive rates were 58% among non-human primates from animal shelters and 38% among those from zoos and academic institutes. Positive reactors were found in three species, the Formosan macaque (Macaca cyclopis; 57%), the cynomolgus macaque (Macaca fascicularis; 11%) and the olive baboon (Papio anubis; 68%). CONCLUSIONS: Our results showed that natural infection by cercopithecine herpesvirus 1 in Formosan macaques was highly prevalent, and to a certain extent reflected the situation of the wild populations in Taiwan. The findings raised the issues of zoonotic public health and the occupational health of primate workers. High positive rate in olive baboons was also found, although, it cannot be ruled out that the positivity was due to cross-reactivity between cercopithecine herpesvirus 1 and other herpesviruses.  相似文献   

13.
The evolution of life history traits is a topic of growing interest in primatology. Traits associated with fertility, such as age at menarche and age at first birth, have great significance for natural selection, and knowing the genetic basis of such demographic traits may improve our understanding of population dynamics. Knowledge of the heritability of reproductive traits may also have practical implications for the management of captive breeding colonies. A maximum likelihood method was used to estimate heritability of age at first birth for a sample of female olive baboons resident at the Southwest Foundation for Biomedical Research. Only animals born at the Foundation that were caged in mixed sex groups and that had previously given birth were included in the sample (n = 316). There were 117 independent individuals and 199 individuals in 35 pedigrees composed of 2 to 26 members. Age at first birth ranged from 3.85 years to 13.11 years. Age at first birth is highly heritable (h2 = 0.87) with no evidence for maternal effects or a dominance genetic component. This level of genetic variability in a fitness-related trait is contrary to evolutionary expectation and may reflect the uniform environment of a captive breeding situation. Thus, the heritability observed in this population may be taken as an upper bound for that in natural populations. © 1995 Wiley-Liss, Inc.  相似文献   

14.
  总被引:2,自引:0,他引:2  
The 'challenge hypothesis' posits that testosterone facilitates reproductive effort (investment in male-male competition and mate-seeking) at the expense of parenting effort (investment in offspring and mates). Multiple studies, primarily in North America, have shown that men in committed relationships, fathers, or both maintain lower levels of testosterone than unpaired men. Data from non-western populations, however, show inconsistent results. We hypothesized that much of this cross-cultural variation can be attributed to differential investment in mating versus parenting effort, even among married fathers. Here, we directly test this idea by comparing two neighbouring Tanzanian groups that exhibit divergent styles of paternal involvement: Hadza foragers and Datoga pastoralists. We predicted that high levels of paternal care by Hadza fathers would be associated with decreased testosterone in comparison with non-fathers, and that no such difference between fathers and non-fathers would be evident in Datoga men, who provide minimal direct paternal care. Twenty-seven Hadza men and 80 Datoga men between the ages of 17 and 60 provided morning and afternoon saliva samples from which testosterone was assayed. Measurements in both populations confirmed these predictions, adding further support to the hypothesis that paternal care is associated with decreased testosterone production in men.  相似文献   

15.
The dung beetle, Scarabaeus catenatus, shows not only the rolling but also the tunneling tactic for nest building with bisexual cooperation. Sex roles, however, differed between the tactics. In rolling, the male took the initiative like that of ball-roller species: he rolled a dung ball away and buried it. In tunneling, in contrast, the male usually had a secondary role like that of tunnelers: he was less active in burrow excavation and provisioning. Regardless of the tactics, male participation did not increase female reproductive output measured by the number or size of brood balls in the field, but seemed to function as mate guarding against conspecific males. This suggests that, in both tactics, the male S. catenatus invests primarily in mating effort compared with paternal effort. The relative importance of mating effort in male participation seems to hold true in other dung beetles, irrespective of whether they are ball-roller or tunneler species. In addition, the male mating strategy of S. catenatus is compared with that of other ball-rollers.  相似文献   

16.
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19.
This study was undertaken to assess the nature of somatomedin-C (SM-C) in baboon (Papio cynocephalus) blood and to compare various methods for estimating SM-C concentrations. Parallel dose-response curves were obtained with normal baboon serum, normal human serum, and purified SM-C. Recovery of purified SM-C added to baboon serum over a wide dosage range (n = 17) was 111 ± 12%, with slightly better recovery at higher potencies. Chromatography of normal baboon serum on Sephadex G-200 at neutral pH produced a profile similar to that observed in the human, as did samples chromatographed on Sephadex G-50 in acid. Although the SM-C content in acid chromatographed plasma was approximately 2.5 times higher than in native unprocessed plasma, there was excellent correlation between the values (r = 0.9143, p < 0.0001). The SM-C in baboon plasma which had been preincubated with glycine HCl was approximately twice that of unprocessed plasma, but the correlation between the two methods was excellent (r = 0.9593, p < 0.0001). The correlation between values obtained after simple acid-ethanol extraction and those observed in unextracted plasma were also significant (r = 0.7689, p < 0.0001). Following a series of four injections of human growth hormone (hGH) to a normal baboon, plasma SM-C rose approximately sevenfold above the initial concentration and returned to basal levels five days after the final injection. These studies show that although the radioimmunoassay (RIA) for SM-C in unprocessed baboon plasma does not measure all of the SM-C present, it provides a reliable index of the total SM-C concentration and reflects GH status in the baboon.  相似文献   

20.
Epidemiological studies were conducted in the Lake Langano area in the Rift Valley of Ethiopia to determine the occurrence of schistosomiasis and assess factors involved in its transmission. Microscopic examination of faecal specimens from free ranging Papio anubis (anubis baboon) troops from Bishan Gari and Burka Dita forest reserves revealed Schistosoma mansoni eggs with a prevalence of 12.1% (11/91) and 26.2%(34/130), respectively. The eggs were viable as confirmed by miracidial hatching and infectivity tests. Out of the total 12 communities (three schools, five villages and one herdsmen community) surveyed for schistosomiasis around Lake Langano, individuals excreting S. mansoni eggs were found in nine communities with prevalence of infection ranging from 1.4 to 43%. The intensity of infection ranged from 24 EPG (eggs per gram of faeces) to 243 EPG. Excretion of viable eggs by the baboons indicate that they play a role in maintenance of S. mansoni infection in the locality. The detection of S. mansoni eggs in young children, collection of cercarial-infected Biomphalaria pfeifferi in water bodies, and establishment of S. mansoni infection in lab-bred mice have confirmed establishment of transmission foci in Kime area, south-east of Lake Langano. However, the lake itself does not seem to support transmission of schistosomiasis since no snails were found along the shore of the Lake. Further investigations are indicated to fully elucidate the role baboons play in the epidemiology of schistosomiasis in the Rift Valley of Ethiopia. The risk of introduction of water-based development projects in these new endemic foci in relation to S. mansoni infection in the baboons is discussed.  相似文献   

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