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There are few reports of coagulation times in marsupial species. Blood samples collected from 14 Bennett's wallabies (Macropus rufogriseus) under anaesthesia during routine health assessments were analysed for prothrombin time (PT) and activated partial thromboplastin time (aPTT) using a point‐of‐care analyser (POC) (Abaxis VSPro®). The wallabies had an aPTT mean of 78.09 s and median of 78.1 s. The PT for all wallabies was greater than 35 s, exceeding the longest time measured on the POC. Although PT was significantly longer, aPTT was similar to the manufacturer's domestic canine reference range.  相似文献   
2.
By 2050, Africa's population is projected to exceed 2 billion. Africa will have to increase food production more than 50% in the coming 50 years to meet the nutritional requirements of its growing population. Nowhere is the need to increase agricultural productivity more pertinent than in much of Sub‐Saharan Africa, where it is currently static or declining. Optimal pest management will be essential, because intensification of any system creates heightened selection pressures for pests. Plant‐parasitic nematodes and their damage potential are intertwined with intensified systems and can be an indicator of unsustainable practices. As soil pests, nematodes are commonly overlooked or misdiagnosed, particularly where appropriate expertise and knowledge transfer systems are meager or inadequately funded. Nematode damage to roots results in less efficient root systems that are less able to access nutrients and water, which can produce symptoms typical of water or nutrient deficiency, leading to misdiagnosis of the underlying cause. Damage in subsistence agriculture is exacerbated by growing crops on degraded soils and in areas of low water retention where strong root growth is vital. This review focuses on the current knowledge of economically important nematode pests affecting key crops, nematode control methods and the research and development needs for sustainable management, stakeholder involvement and capacity building in the context of crop security in East and Southern Africa, especially Kenya, Tanzania, Uganda and Zimbabwe. © 2015 Society of Chemical Industry  相似文献   
3.
大杜鹃(Cuculus canorus)通常寄生小型雀形目鸟类。由于杜鹃雏鸟的排他性拱卵或拱雏,导致宿主繁殖失败,因此宿主进化出如卵识别能力的反寄生策略。反过来,杜鹃也同时进化出如模拟宿主卵的寄生策略。于是两者之间的相互作用可形成类似军备竞赛的协同进化关系。在匈牙利,大苇莺(Acrocephalus arundinaceus)是大杜鹃的主要宿主,寄生率可高达约 40-65%。以往被认为是大苇莺一个亚种的东方大苇莺(A. orientalis)在日本的种群也被大杜鹃寄生(25-40%)。通过采用光纤光谱仪量化大杜鹃及其宿主的卵色特征,我们比较了东、西半球大杜鹃对两种苇莺的寄生模拟程度。鸟类视觉模型显示,对于可见光颜色,杜鹃与宿主之间卵色的模拟程度在匈牙利高于日本,但匈牙利杜鹃和宿主均较大的卵色变异程度可导致卵色模拟困难。杜鹃与苇莺卵色的量度差异在日本较低,这被证明是宿主拒卵行为的一个重要影响因素。苇莺对大杜鹃卵的拒绝率在日本(35%)和匈牙利(37%)相似。与匈牙利不同,在日本,宿主对杜鹃寄生的应对策略如拒卵行为,先于杜鹃的反适应对策。我们认为,两种近缘物种大苇莺对杜鹃寄生的不同反寄生行为,代表了协同进化军备竞赛的不同演化阶段。  相似文献   
4.
始建于16世纪初的拙政园是中国园林的杰出代表,建园之初,文徵明曾多次作有拙政园图。从文氏《王氏拙政园记》和《拙政园卅一图》探析明代拙政园的原貌,可以了解到明代江南文人园林设计的理想品质和"虽由人作,宛如天开"的深邃意境。对当代园林景观建设也有一定的借鉴意义。  相似文献   
5.
BACKGROUND: The tomato red spider mite, Tetranychus evansi (Baker and Pritchard), is a serious pest of solanaceous crops in many African countries. In this study an investigation has been conducted to establish whether mutation of the para‐type sodium channel underlies pyrethroid resistance in T. evansi strains collected in Southern Malawi. RESULTS: Two T. evansi strains from Malawi showed tolerance to the organophosphate chlorpyrifos and resistance (20–40‐fold) to the pyrethroid bifenthrin, but were susceptible to two contemporary acaricides (abamectin and fenpyroximate) in insecticide bioassays. Cloning of a 3.1 kb fragment (domains IIS5 to IVS5) of the T. evansi para gene from pyrethroid‐resistant and pyrethroid‐susceptible strains revealed a single non‐synonymous mutation in the resistant strains that results in an amino acid substitution (M918T) within the domain II region of the channel. Although novel to mites, this mutation confers high levels of resistance to pyrethroids in several insect species where it has always been associated with another mutation (L1014F). This is the first report of the M918T mutation in the absence of L1014F in any arthropod species. Diagnostic tools were developed that allow sensitive detection of this mutation in individual mites. CONCLUSION: This is the first study of pyrethroid resistance in T. evansi and provides contemporary information for resistance management of this pest in Southern Malawi. Copyright © 2011 Society of Chemical Industry  相似文献   
6.
  1. This study aimed to develop an integrated analytical framework to identify candidate sites for surface water protection that is applicable at broad scales and in data scarce regions, using Zambia as a case study.
  2. In the Zambian Water Resources Management Act of 2011, Water Resource Protection Areas are defined as areas where special measures are necessary for the protection of a catchment, sub-catchment, aquifer, or geographical area. Three specific selection criteria are listed for the definition of Water Resource Protection Areas: (i) areas of high importance in providing water to users in a catchment; (ii) aquatic areas of high ecological importance; and (iii) areas that are particularly sensitive to human impact.
  3. In this project, each sub-catchment and river reach of Zambia was characterized for their importance regarding these three criteria. ‘Water provisioning’ was assessed by analysing patterns of runoff generation and human water use; ‘aquatic ecological importance’ was determined by conducting a freshwater biodiversity and ecosystem assessment using a systematic conservation planning approach; and ‘sensitive areas’ were identified by quantifying erosion potential and sediment transport. The work was supported by an assessment of free-flowing rivers in Zambia, i.e., those rivers where aquatic ecosystem functions and services are largely unaffected by changes to fluvial connectivity through dams and other infrastructure.
  4. Highly ranked sub-catchments were found in the Liuwa, Barotse, and Bangweulu floodplains and wetlands, and in the headwater regions of the upper Zambezi, Kafue, Chambeshi/Luapula, and Tanganyika catchments. The Luangwa was identified as the highest ranked candidate river for protection within Zambia.
  5. The resulting maps, data, and methods are intended to support national-scale efforts to prioritize areas for surface water protection, identify catchments and rivers with high conservation value, optimize decision making for infrastructure development, and inform concerted strategies to maintain and restore freshwater ecosystem services in Zambia.
  相似文献   
7.
The reproductive performance of 46 cows in a semi-arid, smallholder farming area of Zimbabwe was monitored for a year. Half the cows were used throughout the monitoring period for various draught purposes, including ploughing and procurement of farm produce for marketing using carts. All the cows lost body weight between July and October, after which the cows that were not worked gained weight until June of the following year. In contrast, the cows that were worked continued to lose body weight until January, throughout the time during which they were used to provide draught power, after which they gained weight. Body weights were significantly higher (p<0.05) in non-working than in working cows in January and February. Ovarian activity was higher (p<0.001) in non-working compared to working cows, particularly between November and February, while calving rates were also higher (p<0.05) in non-working cows. It is concluded that using cows for draught purposes caused loss of body weight and reduced ovarian activity and conception rates.  相似文献   
8.
Veterinary Research Communications - Livestock plays a significant role in the socio-economic development of developing countries by providing livelihood and nutritional security, transport,...  相似文献   
9.
The prevalences of dermatophilosis and parafilariosis were monitored for one year in cattle in Sanyati, a semi-arid smallholder farming area in Zimbabwe. The prevalence of dermatophilosis differed (p < 0.05) with season and among calves, cows, oxen and bulls. In bulls and cows, dermatophilosis lesions were localized mainly to the inguinal regions and between the front limbs. The prevalence and morbidity of dermatophilosis infection were significantly higher (p < 0.05) during the wet season than in the dry season. No mortalities were recorded. The prevalence of parafilariosis was similar to that of dermatophilosis. Infection of cattle by these skin diseases was preceded by high infestation with the tick Amblyomma variegatum. The results suggest that dermatophilosis and parafilariosis have become major diseases that could compromise reproductive performance, draught power availability and overall cattle productivity, particularly during the rainy season in Sanyati smallholder farming area of Zimbabwe.  相似文献   
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