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1.
阐述了南非共和国的自然概况、环境保护、人工种草、良种繁育、饲养管理、科学研究等情况。借鉴南非共和国的经验,提出了发展云南草地畜牧业生产的建议。  相似文献   

2.
The spatial genetic structure of a species, and whether distinct genetic lineages are present, is strongly influenced by their biology and habitat requirements. Given habitat specificity and low vagility, many herpetofaunal species are reservoirs for high levels of cryptic diversity; chameleons are a case in hand. The common flap-necked chameleon Chamaeleo dilepis has a large range that spans much of sub-Saharan Africa. Within South Africa, the species is largely confined to the north-eastern and central areas of the country, and occurs from the coastal forests in southern KwaZulu-Natal westwards into Namibia. Their large range, together with anecdotal evidence that there is considerable morphological and phenotypic diversity across the range, suggests a questionable taxonomy with possible cryptic lineages. The aims of the present study were to investigate whether C. dilepis is genetically structured across parts of its South African range, and whether this species (as it currently stands) might include cryptic lineages. To this end, 72 C. dilepis individuals sampled from four localities across South Africa (Gauteng, n = 2; KwaZulu-Natal, n = 2) were sequenced for two mitochondrial markers (ND4 and 16S). The phylogenetic results suggest that C. dilepis is indeed spatially structured. In addition, the large sequence divergence values between groups strongly suggests the presence of cryptic lineages and, pending the inclusion of more data from a larger geographic range, the group may be in need of a taxonomic revision.  相似文献   

3.
《African Zoology》2013,48(2):359-366
With many species of southern African raptors becoming increasingly threatened, records from rehabilitation centres can give an indication of the threats faced by birds of prey in particular areas and to particular species. Thus, admissions records from a raptor rehabilitation centre in KwaZulu-Natal, South Africa, were analysed for trends. Over eight years (2004–2011), 547 birds from 39 raptor species were admitted to the centre. The majority of individuals were spotted eagle-owls (16.6%), western barn owls (15.2%) and yellow-billed kites (9.7%). The most frequent known causes of injury to raptors were motor vehicle accidents and injuries caused when birds flew into buildings. There was no significant difference in admissions of motor vehicle collision cases between seasons. People generally waited 3.8 days before bringing injured raptors in to the centre, and approximately half of the birds admitted were fed within that time, highlighting a need for public education regarding the general diets of raptors and the benefits of prompt medical attention.  相似文献   

4.
In the savanna rangelands of southern Africa, the debate about land reform tends to be about the redistribution of formerly freehold ranches and fencing-off the rangeland commons into ranches for better-off African farmers. The position of those who favour privatisation has been strengthened by the belief that the only environmentally sound way to manage the range is to subdivide it into private ranches because traditional open-range pastoralism is environmentally destructive. This point of view is at variance with an ever-increasing body of research. Insufficient attention has been given to the sustainable nature of communal rangeland in savanna areas and to the needs of the poor who depend upon them. Following decades of policies that further reduced and fragmented the commonage, governments have the challenging task of developing and implementing policies for those whose livelihoods depend on more secure and sustainable access to the remaining communal rangelands.  相似文献   

5.
6.
南非共和国草地畜牧业考察报告   总被引:1,自引:0,他引:1  
阐述了南非共和国的自然概况、环境保护、人工种草、良种繁育、饲养管理、科学研究等情况。根据南非共和国的经验对发展四川草地畜牧业生产提出了建议。  相似文献   

7.
《African Zoology》2013,48(1):80-90
We studied waterfowl abundance and diversity in relation to season (wet vs dry), wetland characteristics (vegetation and morphometrics) and land-use in a semi-arid agricultural region of South Africa to determine how waterfowl respond to various wetland characteristics, particularly those of permanent agricultural ponds.Wetlands were visited during the wet (n = 215) and dry (n = 178) seasons of 1997 and species' abundances, and wetland and upland characteristics were recorded. Canonical correspondence analyses and multiple regressions determined which wetland and upland characteristics were most strongly associated with waterfowl density and species richness for both the wet and dry season. Overall, diving ducks were not abundant in the wet season, and were rare to absent in the dry season. Divers only responded positively to the characteristics of natural wetlands, including greater surface area, percent coverage of emergent vegetation, and high (ungrazed) shoreline vegetation. Of six species of dabbling ducks present during the wet season, occurrence of three co-varied with wetland and upland characteristics associated with agriculture, namely permanent water, and agricultural grains in the dry season. Being largely grazers, geese responded positively to the higher proportions of bare shoreline, characteristically surrounding agricultural ponds. Because only a few species associated with artificial waterbodies, natural wetlands should be conserved to protect waterfowl diversity in semi-arid South Africa.  相似文献   

8.
《African Zoology》2013,48(4):293-297
Many highly invasive plant species produce fleshy fruit that are consumed and dispersed by frugivorous birds. However, little is known about assimilation efficiency of invasive fruit by indigenous and invasive avian species. We investigated whether indigenous Knysna (Tauraco corythaix) and Purple-crested (Gallirex porphyreolophus) Turacos and invasive alien Rose-ringed Parakeets (Psittacula krameri) met their energy demands when fed fruits of four fleshy- fruited invasive alien plant species: Solanum mauritianum, Cinnamomum camphora, Psidium guajava and Morus alba. Birds were fed single-fruit diets for two consecutive days and energetic parameters were calculated for all fruit diets. Our results showed that generally both invasive and indigenous avian species managed to gain their daily energy requirements from fruits of the four respective invasive plants, suggesting that they can meet their energetic demands by feeding on them only. The exception was P. krameri, which did not feed on S. mauritianum fruit. These findings may explain why fruits of invasive alien plants are attractive to most avian frugivores and highlight the role of avian frugivores in their dispersal.  相似文献   

9.
Relationships between longevity and linear type traits were estimated using data on 34,201 cows with lifetime information and linear type scores. The longevity trait considered was the number of lactations initiated and the linear type traits were rump height, body depth, angularity, rear udder height, fore udder attachment, udder depth, fore teat placement and fore teat length. Fixed effects included in the models were herd year, season of calving and herd-date of classification-classifier and days in milk. Age at first calving and age at classification were included as linear and quadratic covariates. Heritability estimates were low for longevity and moderate for most type traits except rump height and fore teat length. All the phenotypic correlations between longevity and the linear type traits were slightly positive (0.01 to 0.09) except the relationships with rump height and fore teat length which were -0.01 and -0.02, respectively. Genetic correlations between longevity and udder traits as well as angularity were moderate to high and positive (0.22 to 0.48). The only notable negative genetic correlations were longevity with body depth and fore teat length (-0.15 and -0.07, respectively). The genetic correlations suggest that selection for udder traits and angularity should improve longevity in the Holstein cattle population.  相似文献   

10.
《African Zoology》2013,48(1):178-181
The Pacific echiuran species Anelassorhynchus porcellus (Fisher, 1948) was collected from the intertidal rocky shores at Perriers Rock and Isipingo Beach on the KwaZulu-Natal coast. This is the first known record of this species from South African waters. Anelassorhynchus porcellus, originally described by Fisher (1948) from several specimens collected in tidal pools south of Honolulu Harbour, Hawaii was later recorded and described by Edmonds (1960) from specimens collected from Heron Island, Queensland. The discovery of this species from the east coast of southern Africa considerably extends its geographical range. After closer examination of additional specimens of Anelassorhynchus gangae Biseswar, 1984 collected from the Kwazulu-Natal coast it is proposed that this species be recognized as a junior synonym of A. porcellus. Anelassorhynchus porcellus is redescribed and some of the taxonomic characters are reviewed.  相似文献   

11.
In Europe, virological and epidemiological data collected in wild birds and horses suggest that a recurrent circulation of West Nile virus (WNV) could exist in some areas. Whether this circulation is permanent (due to overwintering mechanisms) or not remains unknown. The current conception of WNV epidemiology suggests that it is not: this conception combines an enzootic WNV circulation in tropical Africa with seasonal introductions of the virus in Europe by migratory birds. The objectives of this work were to (i) model this conception of WNV global circulation; and (ii) evaluate whether the model could reproduce data and patterns observed in Europe and Africa in vectors, horses, and birds. The model was calibrated using published seroprevalence data obtained from African (Senegal) and European (Spain) wild birds, and validated using independent, published data: seroprevalence rates in migratory and resident wild birds, minimal infection rates in vectors, as well as seroprevalence and incidence rates in horses. According to this model, overwintering mechanisms are not needed to reproduce the observed data. However, the existence of such mechanisms cannot be ruled out.  相似文献   

12.
《African Zoology》2013,48(2):290-293
Notes on the synonymy of Hexapodibius beasleyi Maucci, 1988, with Haplohexapodibius seductor Pilato & Beasley 1987, are given. Ha. seductor Pilato & Beasley, 1987, is a new record for the African tardigrade fauna.  相似文献   

13.
A total of 231 serum samples were collected from sheep (n=9), goats (n=99) and cattle (n=123) in northeastern KwaZulu-Natal, South Africa. Trypanosome infection was detected using Trypanosoma brucei brucei crude antigen (TbbCA) and T. congolense crude antigen (TcoCA) ELISA assays. Recombinant antigen (T. evansi GM6 which consisted of 4 repeat domains, TeGM6-4r) ELISA and immunochromatographic test (ICT) were also used. Crude antigen ELISA, TeGM6-4r-ELISA and ICT detected 27.3%, 29% and 19.9% of trypanosome seropositive samples, respectively. Trypanosome infection prevalence in cattle and goats was 35.8–46.3% and 0–9.1%, respectively. Out of 9 sheep serum samples, 2–4 sera (22.2–44.4%) were positive. The detection performance of crude and recombinant antigen ELISAs was relatively similar (K=0.6–0.7); both are recommended for reference diagnosis and large scale epidemiological surveys. There is potential application for ICT in on-site diagnosis, but its sensitivity should be improved.  相似文献   

14.
Two introduced beachfleas, Orchestia gammarellus and Platorchestia platensis, have been recorded from South Africa, but have been misidentified by some earlier researchers and, prior to this study, each was also known from just a few, scattered observations, such that their true distributions remained obscure. We illustrate both species to clarify the features that identify and distinguish them and determine their true distributions by re-examining historical samples and by collecting new material from estuaries and lagoons along the west and south coasts of South Africa. Adult males of O. gammarellus have slender antennae and characteristic expanded, flattened, oar-like distal segments on pereopod 7. Adult males of P. platensis have the peduncle of antenna 2 strongly swollen and have bulbous, but not flattened, distal segments on pereopod 7. Both species occur under wrack and other debris along the banks of estuaries and sheltered lagoons. Orchestia gammarellus is found only along the south-west coast, in the Berg River Estuary, Langebaan Lagoon and the Diep River Estuary. Previous records from Knysna were misidentifications of P. platensis. Platorchestia platensis is found at one west coast site, Langebaan Lagoon, but is widely distributed from Cape Point eastwards to at least Algoa Bay. Both species share the same habitats as several other native beachfleas and competitive interactions between native and introduced species merit investigation.  相似文献   

15.
BackgroundDiarrheagenic E. coli (DEC) strains are a major cause of diarrheal diseases in both developed and developing countries. Healthy asymptomatic animals may be reservoirs of zoonotic DEC, which may enter the food chain via the weak points in hygiene practices.AimWe investigated the prevalence of DEC along the pig production continuum from farm-to-fork.MethodsA total of 417 samples were collected from specific points along the pig production system, that is, farm, transport, abattoir and food. E. coli was isolated and enumerated using Colilert. Ten isolates from each Quanti-tray were selected randomly and phenotypically identified using eosin methylene blue agar selective media. Real-time polymerase chain reaction (PCR) was used to confirm the species and to classify them into the various diarrheagenic pathotypes. Antimicrobial susceptibility was determined against a panel of 20 antibiotics using the Kirby-Bauer disk diffusion method and EUCAST guideline.ResultsThe final sample size consisted of 1044 isolates, of which 45.40% (474/1044) were DEC and 73% (762/1044) were multidrug-resistant. Enteroinvasive E. coli (EIEC) was the most predominant DEC at all the sampling sites.ConclusionThe presence of DEC in food animal production environments and food of animal origin could serve as reservoirs for transmitting these bacteria to humans, especially in occupationally exposed workers and via food. Adherence to good hygienic practices along the pig production continuum is essential for mitigating the risk of transmission and infection, and ensuring food safety.  相似文献   

16.
The diversity of Cryptosporidium at species, subtype family and subtype level in diarrhoeic children was investigated in four provinces in South Africa. A total of 442 stool samples from children <5 years of age were collected under a large rotavirus surveillance programme and analysed by Ziehl–Neelsen acid‐fast staining. Fifty‐four (12.2%) were positive for Cryptosporidium, of which 25 were genotyped by polymerase chain reaction (PCR)–restriction fragment length polymorphism (RFLP) and DNA sequence analyses of the 18S rRNA gene. The majority of genotyped specimens were identified as C. hominis (76%), and a high genetic diversity was found with five different C. hominis subtype families (Ia, Ib, Id, Ie and If). Cryptosporidium parvum was found in 20% of the isolates, and three subtype families were identified (IIc, IIe and IIb), with subtype family IIc being the most common. One specimen was identified as C. meleagridis of the subtype family IIId. These results are in accordance with findings from other developing countries and report for the first time the presence in South Africa of C. meleagridis, various subtypes of C. parvum and the subtype family Ie of C. hominis. The results suggest that C. hominis and anthroponotic C. parvum subtypes are the major cause of cryptosporidiosis in South Africa. Further molecular studies are needed to better understand the epidemiology and public health importance of Cryptosporidium in humans in South Africa.  相似文献   

17.
African swine fever virus (ASFV) causes a lethal and contagious disease of domestic pigs. In South Africa, the virus historically circulated in warthogs and ornithodorid ticks that were only found in warthog burrows in the north of the country. Regulations implemented in 1935 to prevent transfer of infected animals or products to the south initially proved effective but from 2016 there have been outbreaks of disease in the south that cannot be traced to transfer of infection from the north. From 1963 there were widespread translocations of warthogs to the south, initially from a source considered to be free of ornithodorid ticks. We undertook to determine whether sylvatic circulation of ASFV occurs in the south, including identification of potential new vectors, through testing extralimital warthogs for antibody and ticks for virus. Results of testing warthogs for antibody and other species of ticks for virus will be presented separately. Here we report finding Ornithodoros (Pavlovskyella) zumpti ticks in warthog burrows for the first time. This occurred in the Eastern Cape Province (ECP) in 2019. Since African swine fever was recognised in the ECP for the first time in 2020 and outbreaks of the disease in domestic pigs continue to occur there, priority should be given to determining the distribution range and vector potential of O. (P.) zumpti for ASFV.  相似文献   

18.
The major developments in southern African herpetology during the last decade are reviewed and first consideration is given to the taxonomic work which is essential to provide a sound foundation for subsequent zoogeographical ecological and ethological research. With the passage of time there will be a gradual shift in emphasis from traditional taxonomic studies to projects based upon living animals both in the field and in the laboratory.  相似文献   

19.
Our objective was to assess the status of the large native rangeland mammals in the eastern and southern African countries focusing on conservation strategies that will benefit the animals, their rangeland habitats, and the people who live in this region. Eastern and southern African rangelands are renowned for supporting a globally unique diversity and abundance of large mammals. This wildlife legacy is threatened by changing demographics, increased poaching, habitat fragmentation, and global warming, but there are reasons for optimism. After sharp declines from 1970 to 1990 across Africa, wildlife populations in some countries have subsequently increased due to incentives involving sport hunting and ecotourism. National parks and protected areas, which have been critically important in maintaining African wildlife populations, are being increased and better protected. Over the past 50 years, the number of parks has been doubled and the areas of several parks have been expanded. The major problem is that no more than 20% of the national parks and reserves set aside for wildlife are adequately protected from poaching. The southern African countries where wildlife has recently thrived have robust hunting and ecotourism programs, which economically benefit private landowners. Considerable research shows rural communities dependent on rangelands can be incentivized to participate in large mammal conservation programs if they can economically benefit from wildlife tourism, sport hunting, and the legal sale of animal by-products. Community-based wildlife conservation programs can be economically and ecologically effective in sustaining and enhancing African wildlife biodiversity, including rhinos, elephants, and lions. Low-input ranching wild ungulates for meat and hunting may be an economically viable alternative to traditional range livestock production systems in some areas. However, in many situations, common-use grazing of livestock and wildlife will give the most efficient use of rangeland forages and landscapes while diversifying income and lowering risk.  相似文献   

20.
《African Zoology》2013,48(2):374-387
During recent decades, most endangered species have suffered serious population declines. Little has been documented on leopards inWest-Central Africa and as a result the efficiency of protection measures and wildlife managing practices can be questioned. Using 416 occurrences of leopards, we investigated the relationship between different environmental factors and leopard distribution to establish a baseline distribution of this feline. Leopards are mainly present in two large populations: one in a forest habitat, the other in a savanna habitat. Leopard populations were found to be associated with lions and hyaenas but they avoided human disturbances. Regarding potential breeding dispersal, the Gaussian representation showed a clear fragmentation among populations, suggesting that long-term survival of the species could be threatened. We found no area to be exempt from threats. The leopard has, however, declined less than other carnivore species and still shows viable populations. Furthermore, occurrences were found to be significantly more numerous than expected in protected areas, suggesting the relative efficiency of conservation.  相似文献   

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