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During 1971-72 contents from the rumens of twenty-two Chanler's mountain reedbuck (Redunca fulvorufula chanleri Rothschild) collected in the Arthur Cole Ranch near Gilgil, Kenya were examined. Frequency of occurrence of monocots averaged 99.5% of identifiable fragments. Frequency of occurrence of monocots in the ground stratum of the vegetation averaged 94% in the areas where mountain reedbuck were collected. Of the 11 grass classifications (seven to species and four to genus) considered reliably identifiable in rumens, three (Themeda triandra, Hyparrhenia spp., and Cymbopogon pospischilii) were taken more frequently than was expected from their occurrence in the vegetation, six (Aristida spp., Cynodon spp., Eragrostis spp., Harpachne schimperi, Microchlva kunthii, and Tragus berteronianus) were taken less frequently, and two (Bothriochloa insculpta and Enneapogon schimperanus) were taken in approximately the same ratio as they occurred in the ground stratum of the vegetation.  相似文献   

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Helminths of mountain reedbuck (Redunca fulvorufula fulvorufula) and gray rhebok (Pelea capreolus) were investigated in South Africa between June 1999 and February 2002. Forty-one mountain reedbuck were culled at Sterkfontein Dam Nature Reserve over 8 different periods, and 25 mountain reedbuck were culled at Tussen die Riviere Nature Reserve over 3 different periods. A total of 17 kinds of helminths were found at the 2 sites, including 15 nematodes, 1 trematode, and 1 cestode. At Sterkfontein, the most prevalent and abundant species were Cooperia yoshidai, Longistrongylus schrenki, and Haemonchus contortus, with the latter 2 being more abundant during November/December than at other times of the year, probably because infective larvae increased on pasture at that time. No statistical differences were found in parasite loads between male and female mountain reedbuck. No correlation was found between fecal egg counts and adult worm counts or between parasite counts and body condition. At Tussen die Riviere, helminths in mountain reedbuck were less prevalent and abundant than at Sterkfontein. The most important species were Nematodirus spathiger, Trichostrongylus falculatus, and Cooperia rotundispiculum. Four gray rhebok died of natural causes at Sterkfontein, from which 5 kinds of helminths were recovered, including C. yoshidai and Paracooperioides peleae.  相似文献   

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The effects of rainfall and temperature on the behavioural ecology of Chanler's mountain reedbuck (Redunca fulvorufula fulvorufula Rothschild) were examined on ranchland near Gilgil, Kenya. Ambient temperature was shown to be the proximate determinant of diurnal activity and rumination patterns. Mountain reedbuck were active during early morning and late afternoon, but rested and abandoned rumination when temperatures peaked at midday. There was close synchrony in levels of activity, rumination and use of cover and shade between males and females. Seasonal variations in time budgets were strongly influenced by rainfall patterns. Analyses revealed a one-month lag between rainfall and both peak grass growth and a decrease in rumination frequency. The proportion of time allocated to feeding decreased one month later, and was coincident with an increase in the proportion of grass in the diet. Reedbuck may therefore be prevented from exploiting high-quality new grass, possibly by gut-fill or induced imbalances in rumen pH. It is suggested that the unexpectedly high levels of browse in the diet is an adaptive response to low rainfall during the preceding two months.  相似文献   

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Reedbuck are heavily dependent on cover as a means of evading predators, and Howard (1986a) suggested that males defend cover-abundant habitat in order to maximize access to receptive females which congregate in these areas. We use a measure of female preference for individual territories, and variations in territory size and quality to test this hypothesis in Chanler's mountain reedbuck (Redunca fulvorufula chanleri). Although the amount of cover within each territory did appear to be important, the height of available slope predicted female preference most precisely. It is concluded that, under certain conditions, the extent of available slopes for predator evasion may be a more appropriate indicator of territory quality.  相似文献   

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Population dynamics of grey rhebok Pelea capreolus and mountain reedbuck Redunca fulvorufula were monitored at Sterkfontein Dam Nature Reserve in South Africa over three breeding seasons. Birth and death rates were recorded in both species, and causes of death were investigated. Immigration and emigration were monitored in grey rhebok. Grey rhebok bred seasonally, with 91% of lambs being born between November and February. The average fecundity rate was 74% and lamb sex ratios were 22M:19F. Mountain reedbuck also bred seasonally, with a birth peak between October and December. The average fecundity rate was 92%, and lamb sex ratios were 12M:8F. Most deaths in both species occurred between June and November each year. Sixteen grey rhebok deaths occurred during the study, of which 10 resulted from hypothermia during one spring snowfall event. This represented 27% of the population at the time. Males and females were affected to the same degree by the snow, but juveniles suffered more than adults. There was no evidence of infectious disease or predation. Forty-three mountain reedbuck deaths occurred during the study, of which 32 resulted from hypothermia following the snowfall. This represented 51% of the population at the time. Females were affected by hypothermia more than males. There was no evidence of disease in the population from the examination of 41 culled animals, and no evidence of predation. Immigration and emigration within the grey rhebok population were uncommon, but dispersal of yearling males occurred every year between October and December when they were evicted from their natal herds. Herd structure of adult animals was very stable. In mountain reedbuck, emigration was very hard to detect.  相似文献   

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Behavioural observations were carried out on grey rhebok and mountain reedbuck at Sterkfontein Dam Nature Reserve, South Africa, for a period of 1 year between May 2001 and April 2002. Four harem herds of grey rhebok, five territorial male mountain reedbuck and female mountain reedbuck (herds grouped as one individual) were monitored to determine activity budgets and activity patterns. Both species spent more time feeding in the late afternoon during relatively cool temperatures, and more time resting in the middle of the day during relatively high temperatures. Statistical comparisons between the two species of the percentage time feeding and resting found no differences between them, although mountain reedbuck spent more time resting overall than grey rhebok. Both species were active at night.  相似文献   

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A total of 3,470 sera, collected between 1963 and 1980 from 45 different species of wildlife in nine African countries, was examined for virus neutralizing (VN) antibodies to bovid herpesvirus 2. Antibodies were demonstrated in 20 species including 15 Bovidae, two Suidae, hippopotamus (Hippopotamus amphibius), giraffe (Giraffa camelopardalis) and a green monkey (Cercopithecus aethiops); 11 of these species had not been previously recorded as sero-positive. Although the significance of neutralizing antibodies in the absence of virus isolation remains in doubt, results suggest that infection is widespread in wildlife. The highest VN titres were recorded in waterbuck (Kobus ellipsiprymnus and K. defassa), reedbuck (Redunca arundinum) and buffalo (Syncerus caffer). Infection appears to be continuous in free-living populations of buffalo and antibodies are present in the majority of animals by the age of 2 yr.  相似文献   

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Pfab  M.F.  Witkowski  E.T.F. 《Plant Ecology》1999,145(2):317-325
Euphorbia clivicola R.A. Dyer is a Critically Endangered Northern Province endemic confined to two populations that have declined drastically over the last decade. One population is protected within a Nature Reserve, while the other occurs in a peri-urban area. In order to determine the causes of the population declines, herbivory damage to plants in both the protected and urban populations was quantified and the effects of herbivory on various aspects of the population biology were assessed. Mountain reedbuck are believed to have been responsible for the herbivory in the protected population. Herbivory on the above-ground branches probably caused the small sizes of protected plants. These were on average less than half the size of urban plants. Herbivory caused a reduction in the number of flowers and fruit produced per protected plant and may have prevented the maturation of flowers into fruit, thereby reducing the total regenerative output of the population. An eight-year absence of fire had resulted in the build-up of a dense moribund grass layer. The selection of E. clivicola plants by mountain reedbuck may therefore have been due to their relatively high nutritional value and accessibility in the thick moribund grass layer. Fencing off the population to prevent entry of herbivores, and implementing a more suitable fire management programme is recommended, as is the adoption of a new IUCN status for the species of Critically Endangered (CR A1).  相似文献   

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Chromosomes of fourteen captive-born mountain reedbucks (Redunca fulvorufula) have been investigated. The diploid chromosome number was 2n = 56 (FN = 60). The mountain reedbuck karyotype consists of 26 acrocentric and two biarmed chromosome pairs resulting from two centric fusions involving chromosomes 2 and 25, and 6 and 10, respectively. In some animals, 57 chromosomes were detected. Variation in the diploid number was found to be due to polymorphism for the centric fusion 6;10. Both X and Y chromosomes are large and acrocentric. The entire Y chromosome and the proximal part of the X chromosome consist of heterochromatin. The chromosomes X, 9 and 14 appeared to be of caprine type. Chromosome aberrations have been detected in two of the 14 animals investigated. A de novo formed Robertsonian translocation rob(6;13) was found in one female heterozygous for the fusion 6;10. CBG-banding revealed one block of centromeric heterochromatin in the de novo formed translocation rob(6;13) and also in the evolutionarily fixed centric fusions 6;10 and 2;25. One examined male homozygous for fusion 6;10, had a mosaic 56,XY/57,XYY karyotype, with 11% of analyzed cells containing two Y chromosomes. The findings were confirmed by cross-species fluorescence in situ hybridization (FISH) with bovine (Bos taurus L.) chromosome painting probes. The study demonstrates the relevance of cytogenetic screening in captive animals from zoological gardens.  相似文献   

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贡嘎山是横断山脉海拔最高的一座大山,是研究山地植物多样性和海拔分布的理想地区。为了探讨贡嘎山地区石松类和蕨类植物多样性组成及海拔分布特点,该研究基于野外考察、标本采集鉴定及文献考证,对贡嘎山地区石松类和蕨类植物进行统计和分析。结果表明:(1)贡嘎山地区有石松类植物3科4属25种,蕨类植物有23科56属291种。(2)主要的珍稀濒危植物有6种,分别是高寒水韭(Iso tes hypsophila)、松叶蕨(Psilotum nudum)、桫椤(Alsophila spinulosa)、小叶中国蕨(Aleuritopteris albofusca)、玉龙蕨(Polystichum glaciale)和扇蕨(Lepisorus palmatopedatus)。(3)优势科为鳞毛蕨科(Dryopteridaceae)75种、水龙骨科(Polypodiaceae)56种、凤尾蕨科(Pteridaceae)54种和蹄盖蕨科(Athyriaceae)37种;优势属为耳蕨属(Polystichum)45种、鳞毛蕨属(Dryopteris)24种、蹄盖蕨属(Athyrium)24种和瓦韦属(Lepisorus)19种。(4)区系以温带成分为主,有286种(93.77%)。随着海拔的上升,石松类和蕨类的物种多样性逐渐增加,2000~3000 m海拔段的物种多样性最高,为20科46属192种,3000 m以上物种多样性逐渐下降,4500 m以上仅分布有4种蕨类植物。此外,该研究还发现,随着海拔的升高,中国-喜马拉雅成分逐渐增加。  相似文献   

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An analysis was carried out on the rumen ciliate population of giraffe. Eight giraffe shot on the Timbavati and adjoining private nature reserves in the north eastern Transvaal, South Africa, were sampled during 1973. Twenty-six species of ciliates were found in the giraffe rumen. Two new species were found and they are described viz. Entodinium longicorpum sp.n. and Eodinium bispinosum sp.n. The genus Ento-dinium with eleven species formed 41% of the total protozoa population. The holotrichs formed 19%, the genus Enoploplastron 16% and Eodinium 11% of the population.  相似文献   

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A new species of Antarctoecia Ulmer, 1907 (Trichoptera: Limnephilidae) from south-eastern Brazil, Antarctoecia brasiliensis sp. nov., is described and figured based on adult male and female specimens from Mantiqueira mountain range, Minas Gerais State. This is the first record of the family Limnephilidae from Brazil.  相似文献   

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Guanshan National Nature Reserve (GNNR) is located in the middle reach of the Jiuling Mountain Range in the southern China and the first national nature reserve within Jiangxi Province. The fish fauna of mountain streams in the GNNR was investigated from September 2006 to August 2007. A total of 379 fish were collected and classified into two families and seven species. Acrossocheilus parallens [relative abundance (RA) 44.3%] was the most abundant fish species. Subdominant species were Onychostoma barbata (RA, 20.3%), Zacco platypus (RA, 14.2%) and Opsariichthys bidens (RA, 12.4%).A greater number of species (7 vs. 2) and individuals (295 vs. 84) were collected from the West Stream compared to the East Stream. Among the seven fish species collected in the GNNR, Acrossocheilus parallens, Onychostoma barbata and Vanmanenia stenosoma are endemic to the Chinese mountain streams. This study suggests that mountain streams in the nation reserves including GNNR are very important for freshwater fish diversity and conservation in Jiangxi Province.  相似文献   

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Abstract: In the southern Rocky Mountains, USA, snowshoe hares (Lepus americanus) and mountain cottontails (Sylvilagus nuttallii) are syntopic. Previous researchers used size of fecal pellets to identify leporid species in the Southern Rockies, a common criterion for identifying species of cervids. We measured 655 fecal pellets from 10 mountain cottontails and 2,374 fecal pellets from 23 snowshoe hares. We found no relationship between the body weight of mountain cottontails and the size of their fecal pellets (r = 0.04, F = 0.01, P = 0.91) but found one for snowshoe hares (r = 0.48, F = 9.3, P = 0.005). Although the 2 species differed in the size of their fecal pellets, the difference between means (1.2 mm) was sufficiently small to require measuring individual pellets and is only applicable to individuals of adult size. Although fecal pellet counts may be used to estimate presence and relative abundance of snowshoe hares in the absence of syntopic leporids, where multiple species of leporids are syntopic this method may yield misleading results.  相似文献   

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Prior to this study, the genus Heraeus Stål, 1862 included 14 species, all of which are restricted to the Western Hemisphere. Three species are known from the Nearctic Region, nine from the Neotropical Region, and two mainly tropical elements are distributed in both regions. In this contribution, we consider Heraeus cincticornis Stål, 1874 a junior synonym of Heraeus elegans (Walker, 1873), select a lectotype for Heraeus coquilletti Barber, 1914, and neotype for Lygaeus triguttatus Guérin‐Méneville, 1857, and describe 28 new species. In addition, the two new genera, Baranowskiobius gen. nov., to include H. elegans (Baranowskiobius elegans comb. nov.) and two new species, and Paraheraeus gen. nov., to include Heraeus eximius Distant, 1882 (Paraheraeus eximius comb. nov.), are described. Previously described species and new taxa are (re)described and illustrated, including male genitalia. Scanning electron micrographs, general habitus photographs, and distribution maps are included for all species studied. A phylogenetic analysis comprising 46 terminal taxa and 50 morphological characters was performed, and five species groups were hypothesized, including the coquilletti, caliginosus, guttatus, illitus, and plebejus groups. All known species of Heraeus and the new genera are included in the phylogenetic analysis. The type species of the genera Myodocha Latreille, 1807, Orthaea Dallas, 1852, and Paisana Dellapé, 2008 are used as out‐groups.  相似文献   

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