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Since dwarf mongooses in captivity show an extremely stable familiar structure with no evidence of group break-up, the study was designed to place the animals under crowding stress to determine whether such tendencies would be manifested and whether compensatory mechanisms to maintain group cohesion are present. A stable family group of 12 animals was investigated and observations over 150 h under control and 120 h under crowded conditions made. The results show that social pressure is mainly exerted on subordinate adult ♂♂ and ♀♀, sometimes resulting in their death by stress-induced uraemia, through increased aggression by the a pair. The social system stabilises after 16 days but high intra-group aggression/submission remains. Synchronisation of oestrus cycles in nubile ♀♀ resulted in simultaneous littering with loss of all young. The significance of these findings for population regulation is discussed.  相似文献   

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Many mammal species adopt marking postures that elevate their scent deposits. The most extreme of these is handstand marking, in which an individual reverses against an upright object, flings its hind legs into the air above its back and balances bipedally on its fore feet. The resulting anogenital deposit is thus raised one full body length above ground level. It has been suggested that this energetically costly form of marking serves to provide conspecifics with information about the marker's body size and hence competitive ability. However, this explanation assumes that the height of an individuals’ deposit does reflect accurately its body size, an assumption that has never been tested in any hand‐standing species. This study investigated the relationship between body size and handstand mark height in a wild population of dwarf mongooses (Helogale parvula) in South Africa. We found that although body size and marking height were correlated positively for female dwarf mongooses, they were not related for males. Male dwarf mongooses (who are subject to intrasexual competition from outside their group) invested more heavily in anogenital range marking, marking at three times the female frequency and placing their deposits significantly higher than females (although they were not dimorphic). Males that were particularly vulnerable to rivals (i.e. those that were small for their age) tended to mark higher than more robust age‐mates, in keeping with the predictions of Adams & Mesterton‐Gibbons’ (1995, J. Theor. Biol.175, 405–421). model of deceptive threat communication. These findings suggest strongly that the height of anogenital scent deposits is of social significance to dwarf mongooses.  相似文献   

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This field study investigated helper behaviour in the care of the young in a small social carnivore, the dwarf mongoose (Helogale parvula). The frequency with which individually marked mongooses, living in six packs, guarded young at the den (babysitting) and brought food to the young was recorded in all-day and morning watches. The principal helpers were the subordinate adult ♀♀ and the yearlings. In a pack of known kinship relationships, an immigrant ♀ did more babysitting than any of the other pack members, all of whom were related to the young. Possible advantages of the aid-giving behaviour to the helpers are discussed.  相似文献   

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杨维康  高行宜 《动物学杂志》2002,37(6):12-12,F001
波斑鸨(Chlamydotis undulata)属鹤形目鸨科,体重1~2.5 kg.  相似文献   

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Here we present a new set of 22 microsatellite loci isolated from Chlamydotis undulata undulata, an endangered Houbara bustard found across North Africa. The number of alleles per locus ranged from one to nine, and heterozygosities ranged from 0.167 to 0.944. Total exclusionary probabilities using these loci for the first and the second parent were 0.992932 and 0.999915, respectively. Successful cross‐amplification was observed in eight other Otididae species (12–22 of the 22 loci). These microsatellite markers are powerful tools for genetic identification, paternity assignment and population genetic studies.  相似文献   

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The houbara bustard (Chlamydotis undulata undulata) is endangered in North Africa. Through a captive-breeding program established in Morocco by The Emirates Center for Wildlife Propagation, wild populations are being supplemented by the releasing of captive-reared birds. Newcastle disease, which is caused by Newcastle disease virus (NDV; Avian paramyxovirus type 1), can infect houbara bustards and is a significant threat through contact with backyard poultry and possibly wild birds. Three vaccination schedules for Newcastle disease were evaluated by serologic monitoring to assess the efficiency and safety of various types of vaccines (live vs. inactivated), vaccine strains (Hitchner B1 and Clone 30), and administration routes (intranasal vs. injection). We evaluated antibody titers in 211 adult houbara bustards for 10 mo. Antibody titers to NDV in both sera and egg yolks were monitored by hemagglutination inhibition test. The inactivated vaccine provided a high, homogeneous, and durable serologic response in breeders; titers were higher than log2 11 after 4 wk and remained higher than log2 7 after 10 mo. The response to the two live vaccines was similar, and antibody titers did not exceed log2 6 at sero-conversion. Maternally derived antibodies were efficiently transmitted in vitellus, further confirming that offspring of females hyperimmunized with the inactivated vaccine received high titers of maternal antibodies.  相似文献   

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A Moroccan Houbara Bustard pedigree was analyzed to evaluate the genetic variability in captive breeding population using genealogical approaches. The whole Houbara breeding flock (WP) for the period 1993–2004 was made up of 531 birds comprising 346 females and 185 males. The reference population (RP) comprised 198 individuals ready for reproduction from 2000 to 2004 cohorts. The corresponding percentage of known ancestors was estimated as 98.23% for the parent generation, 41.19% for the grandparent generation and 7.00% for the great grandparents generation. The average generation interval for Houbara was computed as 4.64 years. Genetic variability loss per generation was ascertained using the effective population size (), the founder genome equivalent (fge), the effective number of ancestors and founders (fa) and (fe), respectively, for the RP and across each cohort. The results showed no bottleneck events in the breed but some loss of genetic variability just after the initiation of the conservation program. However, the annual effective population size based on the realized increase in inbreeding () was estimated to be 207 for the RP and 1,000 for the WP. With regard to conservation breeding schemes, the genealogical evidence presented here is very useful as it revealed the positive effect of migration on Houbara breeding. The mating strategies will assist in the future control and management of the genetic variability of this population. Zoo Biol. 32:366‐373, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   

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The current range and relative abundance of the Egyptian Mongoose Herpestes ichneumon (L.) in Portugal were studied using data obtained through direct field observations, personal communications and answers to enquiries. The present northern limit of its distribution has extended well beyond the Tagus River in most of its Portuguese range, indicating a probable expansion in recent years. A consistent increase in abundance was detected from north to south, latitude being highly correlated with computed indices of Mongoose abundance. The best-fit model for predicting Mongoose relative abundance in the country considers latitude and human population density simultaneously. Altitude is the only environmental variable significantly correlated with the Mongoose abundance once the influence of latitude is discounted. Available information appears to indicate that the Portuguese Mongoose population is increasing, nevertheless research is needed in order to assess the impact of current predator control schemes on local populations.  相似文献   

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Four phenylpropanoids, forsythoside B 1, lysionotoside 2, verbascoside 3, betonyoside F 4, an iridoid, verminoside 5, seven flavonoids, compounds 612, and two betaine derivatives 13 and 14 were isolated from the aerial parts of Ballota undulata. The structures of the isolated compounds were established by high resolution NMR and ESI-MS. The antioxidant activity of all compounds was determined by measuring free radical scavenging activity by TEAC test.  相似文献   

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Individual specificity can be found in the vocalizations of many avian and mammalian species. However, it is often difficult to determine whether these vocal cues to identity rise from “unselected” individual differences in vocal morphology or whether they have been accentuated by selection for the purposes of advertising caller identity. By comparing the level of acoustic individuality of different vocalizations within the repertoire of a single species, it is possible to ascertain whether selection for individual recognition has modified the vocal cues to identity in particular contexts. We used discriminant function analyses to determine the level of accuracy with which calls could be classified to the correct individual caller, for three dwarf mongoose (Helogale parvula) vocalizations: contact, snake, and isolation calls. These calls were similar in acoustic structure but divergent in context and function. We found that all three call types showed individual specificity but levels varied with call type (increasing from snake to contact to isolation call). The individual distinctiveness of each call type appeared to be directly related to the degree of benefit that signalers were likely to accrue from advertising their identity within that call context. We conclude that dwarf mongoose signalers have undergone selection to facilitate vocal individual recognition, particularly in relation to the species’ isolation call.  相似文献   

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Species range-limits are influenced by a combination of several factors. In our study we aimed to unveil the drivers underlying the expansion of the Egyptian mongoose in Portugal, a carnivore that was confined to southern Portugal and largely increased its range during the last three decades. We evaluated the expansion of the species in three periods (1980-1990, 1990-2000 and 2000-2010), by projecting the presence/absence data of the species in each temporal range and proposed four hypotheses to explain this sudden expansion associated to changes in the barrier effects of human infrastructure and topographic features, and in the availability of suitable areas due to climate change or land use. An exploratory analysis was made using Spearman rank correlation, followed by a hierarchical partitioning analysis to select uncorrelated potential explanatory variables associated with the different hypotheses. We then ran Generalized Linear Models (GLM) for every period for each hypothesis and for every combination of hypotheses. Our main findings suggest that dynamic transitions of land-use coupled with temperature and rainfall variations over the decades are the main drivers promoting the mongoose expansion. The geographic barriers and the human infrastructures functioned as barriers for mongoose expansion and have shaped its distribution. The expansion of the Egyptian mongoose across the Portuguese territory was due to a variety of factors. Our results suggest a rapid shift in species range in response to land-use and climate changes, underlining the close link between species ranges and a changing environment.  相似文献   

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