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21.
Tertiary lymphoid organs (TLOs) are structures that are morphologically and functionally similar to secondary lymphoid organs. TLOs usually arise in a background of chronic inflammation. Several histological patterns of interstitial nephritis have been documented in porcine leptospirosis. Among them the lympho-follicular pattern is characterized by infiltrates of mononuclear cells organized in lymphoid follicle-like structures. Immunohistological analysis of 5 cases of porcine lympho-follicular nephritis associated with Leptospira Pomona infection demonstrated the presence of inflammatory cell populations, including B cells, T cells, macrophages and follicular dendritic cells (FDCs), which were compartmentalized as in TLOs. Immunohistochemistry for Leptospira Pomona revealed an intimate association between leptospiral antigen and FDCs. Overexpression of MHCII in different populations of both professional and non-professional antigen presenting cells was also demonstrated. FDCs play role during TLOs induction for their ability to retain non-self antigens in the form of immune complexes, thus causing persistent T cell activation, generation of a complex cytokine network and stimulation of humoral immunity. Sustained bacterial antigen presentation in the context of chronic leptospiral nephritis, may also lead to autoimmune mechanisms involved in the generation of TLOs. Whether lymphoid neogenesis and TLOs play a protective role in porcine leptospiral nephritis is still unclear.  相似文献   
22.
Thirty-one samples of pasture grass from districts surrounding Karatina, Kenya were analysed for contents of copper, molybdenum, zinc and sulphur. The following mean values and standard deviations were found: Copper: 8.2 +/- 5.0 mg/kg DM; molybdenum: 1.4 +/- 2.6 mg/kg DM; zinc: 33 +/- 10 mg/kg DM and sulphur: 0.17 +/- 0.06% DM. Mean value of the ratio between copper and molybdenum was 13 +/- 11. Samples of cattle liver (n = 96) and sheep liver (n = 93) were analysed for copper and zinc with the following results: Cattle liver: 21 +/- 16 mg Cu/kg WW and 37 +/- 11 mg Zn/kg WW. Sheep liver: 59 +/- 37 mg Cu/kg WW and 30 +/- 6.4 mg Zn/kg WW. It is concluded that subclinical copper deficiency may occur in cattle in the districts included in the investigation. The copper status of sheep seems to be adequate. The levels of zinc may indicate a marginal intake of this element in sheep.  相似文献   
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This paper reviews literatures on Web geographic information system decision support system (Web GIS DSS), its development, and applications in irrigation water management. The purpose is to summarize and synthesize the most useful approach used in developing web applications for irrigation water management. It encompassed varieties of reports and publications for wider understanding of the topic. The review provides the concept, methodologies, and various uses of the applications. Critical analysis on the choice of structural framework and Graphical User Interface has been discussed. Among problems encountered during system development were: data management, security, user needs, etc. The use of Web GIS DSS is gaining more attention from Irrigation Engineers, System Developers, and Cartographers. Web GIS and especially the real-time capability can be of importance in solving many problems regarding irrigation water management. When system is well design, it can be safe, cheap, and maximize profit of any business. The future of development and application of web GIS applications were well discussed by presenting the latest technology in the systems development. There is need for standardization of some aspect of methodologies issues concerning information security and customization to ensure flexibility and viability. The web GIS is simply the future of many spatial transactions.  相似文献   
25.
The apparent digestibility of protein, organic matter and energy of high‐fibre and fibre‐reduced sunflower cakes, Kenya's ‘omena’ fishmeal, anchovy fishmeal and wheat bran were investigated in tilapia Oreochromis niloticus (L.) fingerlings. The feeding values and protein qualities of the above ingredients were also determined at two dietary protein levels. Fourteen diets were formulated, and each was provided to three tanks containing 12 fish in Expt 1 (digestibility study) and 25 fish in Expt 2 (feeding trial). Water temperatures and dissolved oxygen concentrations were maintained above 26 °C and 5.5 mg L?1 respectively. Anchovy and ‘omena’ fishmeals each had an apparent digestibility coefficient for protein (ADC‐P) of 90%, whereas the fibre‐reduced and high‐fibre sunflower cakes had ADC‐P values of 89% and 86%. Wheat bran had an ADC‐P value of 75%, which was significantly lower than those found for the other test ingredients. Apparent digestibility coefficients for energy (ADC‐E) and digestible energy values (DE) were 86% and 78% and 4003 kcal kg?1 and 3624 kcal kg?1 for anchovy and omena fishmeals respectively. The corresponding values for the plant protein sources were 42% and 30% and 2200 kcal kg?1 and 1400 kcal kg?1 for the fibre‐reduced and high‐fibre sunflower cakes respectively. Diets based on the fibre‐reduced cake had higher levels of all amino acids than those based on the high‐fibre cake. Fish fed diets with 30% protein gained 40 g and had a feed conversion ratio (FCR) of 1.87, whereas those fed diets with 20% protein gained 35 g and had a FCR of 2.2. The source of protein had a significant effect on weight gain.  相似文献   
26.
The objective of this study was to determine the effect of replacing fishmeal with high‐fibre and low‐fibre sunflower cakes (HFSC and LFSC) on whole body fatty acid composition in tilapia Oreochromis niloticus (Linn). Sex‐reversed O. niloticus males with an initial weight of approximately 16g ± 0.95 (SD) were used. A control diet based on herring meal and soybean meal was formulated. Six test diets were formulated such that low‐fibre (LF) and high‐fibre (HF) sunflower cakes (SC) contributed 30%, 60% and 80% of the dietary protein, and the diets were designated as LFSC‐30, LFSC‐60, LFSC‐80, HFSC‐30, HFSC‐60, and HFSC‐80 respectively. All fish were held at 25–28°C. They were fed three times daily their prescribed experimental diets for 70 days. At the end of this period they were starved for 24 h and weighed. Five fish representing the average weight of each replicated group (n=3) were frozen in plastic bags at –22°C for determination of fatty acid composition. Fatty acids in the fish were significantly influenced by diet. Palmitic, oleic and linoleic acids were the most abundant fatty acids in both the diets and the fish. Linoleic acid (18:2 ω6) was the most abundant fatty acid in diets based on sunflower cake. The levels of this fatty acid were also higher in fish fed diets with high contents of the sunflower cakes (LFSC‐60, LFSC‐80 and HFSC‐80) (31.3%, 34.7% and 29.7% respectively) than fish fed the control diet (13.8%). Percentages of long chain polyunsaturated acids of the ω‐3 family viz., docosahexaenoic (22:6 ω3) and eicosapentaenoic (20:5 ω3) were low in the diets and in the fish bodies. Fish fed the control diet had a higher level of 22:6 ω3 than those fed the other diets. The possible implications of the preceding findings for human health will be discussed.  相似文献   
27.
Tropical Animal Health and Production - This paper highlights the factors likely to influence the economic efficiency of small-scale dairy farms in Mukurweini, Nyeri County, Kenya. A total of 91...  相似文献   
28.
Journal of Plant Diseases and Protection - The influence of four carrier-solvents (acetone, ethanol, petroleum ether and hexane) on the efficacy of neem (Azadirachta indica A. Juss) seed oil...  相似文献   
29.
A clinical trial was conducted to test buparvaquone (Butalex; Coopers Pitman-Moore) in the treatment of East Coast fever under field conditions in Kenya. Data from 229 cases were analysed following treatment with one (69), two (142) or three (18) doses at 2.5 mg/kg. The majority of cattle (95.2 per cent) were exotic (Bos taurus) or improved (Bos taurus cross Bos indicus) and 39.3 per cent were infected with Anaplasma marginale. There was an overall recovery rate of 85.6 per cent, with 90.1 per cent recovering following one treatment and 75.4 per cent recovering following two treatments. At a follow-up visit three to six months after completion of the trial data was obtained on 224 cases. Thirty had died, 13 of which were reported to have been from East Coast fever, nine had been sold and six slaughtered. Of the remaining 146, 86.3 per cent were in good condition, 13.7 per cent fair and 2.0 per cent in poor condition. A two dose regimen was most effective and should be recommended except in very early cases or those under direct veterinary supervision.  相似文献   
30.
The occurrence of cross-resistance among melarsoprol-resistant Trypanosoma brucei rhodesiense isolates was investigated in this study. The isolates, T. b. rhodesiense KETRI 237, 2538, 1992, 2709, 2694 and 3530, had been obtained from sleeping sickness patients in Kenya and Uganda between 1960 and 1985. Five groups consisting of six mice each were inoculated intraperitoneally with 10(5) parasites of each isolate, and 24 h later treated with either melarsoprol, homidium chloride, diminazene aceturate or isometamidium chloride. The control group comprised infected but untreated mice. The mice were monitored for cure for a period of 60 days post-treatment. The mean prepatent period in the control mice was 5 days while the mean survival period was 22 days. Five of the stabilates, KETRI 237, 2538, 2709, 2694, and 3530, were confirmed to be melarsoprol resistant. Cross-resistance was observed, with the majority of the isolates being resistant to homidium chloride (5/6) and diminazene aceturate (5/6), but all were sensitive to isometamidium chloride (6/6). However T. b. rhodesiense KETRI 1992, which was previously considered as melarsoprol resistant, was sensitive to all the drugs tested. In conclusion, our study has revealed the existence of cross-resistance among the melarsoprol resistant isolates which could only be cured by isometamidium.  相似文献   
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