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911.
Pseudogout, the acute form of calcium pyrophosphate deposition disease, is a common condition in elderly human beings and is characterised by the sudden onset of intense joint pain and synovitis. It is rarely identified in animals but was diagnosed in two dogs that presented with acute lameness and pyrexia. Cytology of the synovial fluid showed a mildly elevated cell count with both non-degenerate neutrophils and mononuclear cells present. Many of the mononuclear cells and occasional neutrophils contained square or rhomboid-shaped crystals that were variable in shape and size and weakly birefringent on examination under polarised light. Clinical signs resolved following treatment with prednisolone. 相似文献
912.
A 3.5-month-old papillon puppy was brought to our clinic with chief complaints of progressive quadriparesis, ataxia and head tremor. Lesions in the cerebellum, brainstem and spinal cord were suspected on the basis of a neurological examination. No abnormality was found in a clinicopathological examination or on magnetic resonance imaging. On the basis of these results differential diagnoses including an inflammatory disease, a degenerative condition or a storage disorder were considered. Subsequently, the signs progressed and glossoplegia and dysphagia developed at six months of age. At a second magnetic resonance imaging, severe atrophy of the entire brain was found. After these examinations, the puppy was euthanased and histopathologically diagnosed with neuroaxonal dystrophy. Because magnetic resonance imaging detected abnormal features that were characteristic of neuroaxonal dystrophy in this case, we speculate that magnetic resonance imaging can assist in the pre-mortem diagnosis of this disease. 相似文献
913.
Labuschagne K Gerber LJ Espie I Carpenter S 《The Onderstepoort journal of veterinary research》2007,74(4):343-347
Culicoides biting midges (Diptera: Ceratopogonidae) are responsible for the transmission of a large number of pathogens to livestock and wild animals. In this study the presence of the genus, using light traps based at four different sites within the National Zoological Gardens of South Africa, was investigated during 2002-2004. In total, 37 species were recorded, including large numbers of Culicoides imicola Kieffer, 1913, which is responsible for the transmission of economically important arboviruses in South Africa, Europe, Middle and Far East. These results are discussed with reference to the wider Culicoides fauna in the Onderstepoort area of South Africa, their vector competence as well as biosecurity at the National Zoological Gardens. 相似文献
914.
Kate L. Constantine Fernadis Makale Idah Mugambi Duncan Chacha Harrison Rware Alexander Muvea Vincent K. Kipngetich Justice Tambo Adewale Ogunmodede Djami Djeddour Corin F. Pratt Ivan Rwomushana Frances Williams 《Pest management science》2023,79(11):4343-4356
Background
In Kenya, rice (Oryza sativa L.) is mainly produced under irrigation by small-scale farmers. Mwea irrigation scheme (MIS) in Kirinyaga County accounts for 80–88% of rice production. Here, rice is the main source of livelihood and a source of revenue generation for the county. However, a recently established invasive freshwater snail, Pomacea canaliculata (Lamarck) (family: Ampullariidae), a species of apple snail, presents a serious threat to rice production.Results
Household surveys, focus group discussions and key informant interviews highlight apple snail as a serious problem in MIS. Households that observed at least a moderate level of infestation (>20% of cultivated area) experienced significant reductions in rice yield (~14%) and net rice income (~60%). Farmers reported increased use of chemical pesticides for management of apple snail. In addition, the cost of hired labor for physical removal of egg masses and snails is resulting in substantial negative effects on net income. Farmer age, area of land owned, responsibility for decision-making, receipt of extension advice, training, and membership of a farmer organization, were all statistically significant variables to explain farmers awareness of the need for area-wide apple snail management.Conclusion
Strategies to limit the spread of apple snail are urgently needed. A Multi-Institutional Technical Team (MITT) has been established to spearhead management efforts and consolidate advice to farmers on how to manage apple snail. However, without action to mitigate spread, the consequences could be disastrous for rice production and food security in Kenya, and for other rice growing regions across Africa. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. 相似文献915.
Kara A. Brown Amy L. Johnson Susan J. Bender Thomas J. Nolan Bianca Pfisterer JoAnn Slack Elinor Willis Emily K. Rule 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2023,37(2):735-739
A 5-year-old imported Zangersheide gelding was evaluated for SC swellings over both forelimbs and lameness localized to the distal metacarpus. Ultrasound examination of the SC masses was compatible with verminous granulomas. Linear hyperechoic foci were present within the suspensory ligament branches of both forelimbs, suggestive of ligamentous parasitic infiltrates. A diagnosis of onchocerciasis was confirmed on biopsy of a SC mass. The gelding was treated with ivermectin and a tapering course of PO dexamethasone but was eventually euthanized. Necropsy confirmed the presence of SC eosinophilic granulomas and degenerative suspensory ligament desmitis, both with intralesional nematodes. Given the location and appearance of the nematode, a diagnosis of Onchocerca sp., most likely O. reticulata, was made. Onchocerciasis should be included as a differential diagnosis for multifocal suspensory ligament desmitis with these sonographic characteristics when paired with SC masses in imported European Warmbloods. 相似文献
916.
G. S. Chaturvedi P. K. Aggarwal A. K. Singh M. G. Joshi S. K. Sinha 《Irrigation Science》1981,2(4):225-235
Summary The effect of irrigation on tillering and tiller mortality in varieties of wheat (Triticum aestivum and T. durum), triticale and barley was studied under field conditions. Low temperature in the early stages of growth promoted production of tillers whereas increase in temperature during extension growth phase increased tiller mortality. More than 1000 tillers m–2 were produced with five irrigations but 40% or more died. With limited water availability tiller production was reduced but so was their mortality. Grain yield in wheat and triticale was positively correlated with productive tillers and negatively correlated with the maximum number of tillers produced in wheat and barley grown under limited irrigation conditions. Varieties with a capacity to produce fewer tillers were identified. Some of them proved more stable in yield. No correlation was found between tiller number and grain yield in the frequently irrigated treatment. 相似文献
917.
R. L. McCown B. H. Wall P. S. Carberry J. N. G. Hargreaves K. L. Green P. L. Poulton 《Irrigation Science》1990,11(3):189-195
Summary This paper reports on the design and performance of an irrigation system associated with a rain shelter. The shelter is used in the closed position as a platform for multiple spray lines. This system automatically supplies, at a specified time, water of specified depth and delivery rate, either uniformly or on a specified gradient across the sheltered area. Variations in crop water deficits and yields have conformed closely to imposed water gradients. 相似文献
918.
Photosynthesis,plant growth and dry matter distribution in kiwifruit as influenced by water deficits 总被引:1,自引:0,他引:1
The effects of water deficits on photosynthesis, plant growth and dry matter accumulation and distribution in the kiwifruit, cv Hayward, grown under controlled conditions in the glasshouse were studied. Water stress was imposed by irrigating the plants with 100%, 85%, 65% and 40% of water needed to reach pot capacity in the soil. Water deficits reduced the rate of photosynthesis by up to 53–64% in relation to the control. This decline was attributed to stomatal closure, since stomatal conductance was reduced significantly, or/and to inhibition of photosynthesis at chloroplast level. Severe water stress reduced plant height by 78–84%, total dry weight by 58–66% and total leaf area by 72–77%. The root to shoot ratio was 3.5 times higher in water-stressed plants, showing that water stress in kiwifruit alters the pattern of dry matter distribution favouring the roots. The decrease in growth induced by water deficits was a consequence of a reduction in both photosynthesis and photosynthates partitioning, which adversely affects leaf area development. 相似文献
919.
920.
Arable land in western Kenya is under considerable pressure from increasing human population. Rural households depend on farming for at least part of their livelihood, and poverty rates are among the highest in Kenya. Land is often depleted of nutrients, and for most farmers, access to inputs and markets is poor. There is a need to identify options that are manageable within the context of the farmer’s resource base and the household’s objectives that could improve farm household well-being. In this study we integrated qualitative informal participatory approaches with quantitative mathematical programming and biophysical simulation modelling. Households in four sub-locations in Vihiga District were clustered and pilot cases identified. Meetings were held with farmers to elicit their perceptions of what their ideal farm would look like, and how its performance might compare with their own farm’s performance. With farmers’ help, a range of scenarios was analysed, relating to changes in current enterprise mixes, changes in current farm sizes, and changes in prices of staples foods and cash crops. A considerable mismatch was found between farmers’ estimates of their own farm’s performance, and what was actually produced. There seems to be a threshold in farm size of 0.4 ha, below which it is very difficult for households to satisfy their income and food security objectives. Even for larger farms whose households are largely dependent on agriculture, the importance of a cash crop in the system is critical. There is a crucial role for extension services in making farmers aware of the potential impacts on farm revenue of modest changes in their farm management systems. We are monitoring nine households in the district, whose farmers have made some changes to their system in an attempt to increase household income and enhance food security. 相似文献