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61.
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63.
Resistance to early blight of tomato with respect to various parameters of disease epidemics 总被引:3,自引:1,他引:2
Koshlendra Kumar?PandeyEmail author Padma Kant?Pandey Gautam?Kalloo Malay Kumar?Banerjee 《Journal of General Plant Pathology》2003,69(6):364-371
Resistance to early blight in the tomato was assessed by examining various parameters of the progress of the disease. Artificial inoculation and the scoring technique were standardized. Test plants were inoculated with 125cfu/ml of a 12-day-old culture of a pathogenic isolate of Alternaria solani. Screening under artificial conditions was more informative than that under natural epidemic conditions. Tomato cultivars CLN-2071-C, CLN-2070-A, BSS-174, and DTH-7 with resistance expressed as slow blighting against four pathogenic isolates of A. solani, were selected for cultivation in disease-prone areas. Disease intensity increased with the age of plants under the same inoculum load. The area under the disease progress curve (AUDPC) was positively correlated with the percentage disease index and negatively with resistance. Calculation of the apparent infection rate (r) was more informative for natural epidemics than for artificial conditions. The sequential apparent infection rate between observation periods was better correlated with disease progress than was the total apparent infection rate between the first and last observations. A double sigmoidal disease progress curve during the same cropping season was characteristic of some varieties when fungal infection took place during the vegetative phase of crop growth. 相似文献
64.
The most variable region of the cytochrome oxidase I (COI) gene of Hypoderma bovis(1) and Hypoderma lineatum(2) (Diptera, Oestridae) was amplified by PCR and the amplicons were sequenced and analysed. PCR products were digested with three restriction enzymes, namely BfaI, HinfI and TaqI, providing informative profiles. H. bovis and H. lineatum sequences revealed an inter-specific variation rate of 8.5%, and an intra-specific variation rate of 0.87 and 0.29%, respectively. The results showed that the COI gene region examined was useful for the differentiation of H. bovis and H. lineatum and that a PCR-RFLP assay is a practical tool for their identification, offering additional diagnostic and epidemiological instruments for the study of cattle grub infestation. 相似文献
65.
Kumar N Sharma AK Sharma AK Kumar S 《Journal of veterinary medicine. A, Physiology, pathology, clinical medicine》2002,49(5):269-276
The efficacy of carbon fibres and plasma-preserved tendon allografts for gap repair in the superficial digital flexor tendon in the mid-metatarsal region was evaluated in 12 crossbred calves. Experimental tenectomies were performed, followed by implantation of carbon fibres in group I (12 legs) and plasma-preserved tendon allografts in group II (12 legs). Gross observations in group I showed filling of the defect with granulation tissue with more vascularity on day 7, which was less prominent at day 14. On day 30, the neotendon formed was slightly thicker and comparable to normal tendon in appearance and texture. On day 90, it exhibited all the characteristics of a fully developed tendon. Whereas, in group II increased vascularity at the site and encapsulation of the graft with connective tissue in early periods was observed. The gap between graft and host was filled with fibrous connective tissue. Peritendinous adhesions were maximum on day 7 which were gradually reduced in both groups. Microscopically, an acute inflammatory reaction in the periphery of carbon fibres was observed on day 7. Immature fibroblasts were arranged in a haphazard pattern at this stage. By day 14, numerous newly formed capillaries and comparatively more mature fibroblasts were present in between and around the carbon fibres which were aligning parallel to the longitudinal axis of the tendon. By day 30 the healing tissue exhibited longitudinal orientation of collagen fibres and was at a more advance stage of maturation. By day 90, the neotendon formed simulated the picture of normal tendon. In the grafted tendon group, there was normal healing tissue at the functional sites between host and grafted tendon. The fibroblastic activity appeared to be both extrinsic and intrinsic in origin. The connective tissue had invaded the graft to a variable distance and there was resorption of graft which was replaced by newly formed connective tissue on day 90. Scanning electron microscopic observation revealed formation of neotendon between carbon fibre strands, resulting in thickening of the implant. In later stages parallel collagen fibres resembling normal tendon were observed in both groups. 相似文献
66.
This study was carried out to identify immunoreactive polypeptides in Babesia equi merozoite antigen. Three fractions of killed B. equi merozoite antigen viz.; whole merozoite (WM), cell membrane (CM) and high speed supernatant (HSS) antigens were prepared from the parasite infected erythrocytes. These antigenic preparations along with ghost antigen from non-infected erythrocytes were fractionated on 12% sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblotted with sera showing high antibody titres. On SDS-PAGE, 16 polypeptides with molecular weight (Mr) in the range of 112-17kDa were obtained from the WM and CM antigens. But only six polypeptides were detected (96.5-28kDa) in the HSS antigen. On immunoblotting with high titred serum collected from donkeys following two immunizations with a killed B. equi merozoite immunogen, 11 polypeptides were observed in the WM and CM antigens (Mr 112-18kDa). Of these, four polypeptides (Mr 112, 45, 33 and 18kDa) were identified as most immunoreactive. Besides these, a 28kDa was observed as strong immunoreactive protein in WM and CM antigens. The HSS antigen showed only six polypeptides and one peptide (28kDa) was identified as immunoreactive. When high titred serum collected from immunized donkeys following challenge with B. equi infected blood and was used for immunoblotting, the protein profile of WM and CM antigens remained the same. However, three additional polypeptides (Mr 81, 54.5 and 39kDa) were detected in HSS antigen. 相似文献
67.
Kirker-Head CA Chandna VK Agarwal RK Morris EA Tidwell A O'Callaghan MW Rand W Kumar MS 《American journal of veterinary research》2000,61(6):714-718
OBJECTIVE: To correlate substance P content of synovial fluid with prostaglandin E2 content, radiographic evidence of joint abnormality, and anatomic location of the joint for normal and osteoarthritic joints of horses. SAMPLE POPULATION: Synovial fluid from 46 normal joints in 21 horses and 16 osteoarthritic joints in 10 horses. PROCEDURE: Normal and osteoarthritic joints were identified by clinical and radiographic examination, by response to nerve blocks, during scintigraphy or surgery, or by clinicopathologic evaluation. Substance P and prostaglandin E2 contents of synovial fluid were determined by radioimmunoassay. Radio-graphs of joints were assigned a numeric score reflecting severity of lesions. Joints were assigned a numeric score reflecting anatomic location. RESULTS: Median concentrations of substance P and prostaglandin E2 were significantly increased in osteoarthritic joints, compared with normal joints. A significant correlation was found between concentrations of substance P and prostaglandin E2 in synovial fluid, but a correlation was not detected between substance P concentration in synovial fluid and anatomic location of the joint or between radiographic scores of osteoarthritic joints and concentrations of substance P or prostaglandin E2. CONCLUSIONS AND CLINICAL RELEVANCE: A correlation existed between concentrations of substance P and prostaglandin E2 in synovial fluid obtained from normal and osteoarthritic joints. However, content of substance P in synovial fluid cannot be predicted by the radiographic appearance of the joint or its anatomic location. Substance P and prostaglandin E2 may share an important and related role in the etiopathogenesis of osteoarthritis, lending credence to the importance of neurogenic inflammation in horses. 相似文献
68.
Tropical Animal Health and Production - 相似文献
69.
Jamie M Bush Doreene R Hyatt Denise Bolte Karamjeet Pandher 《Journal of veterinary diagnostic investigation》2006,18(6):594-596
A 700-pound, 9-month-old Angus heifer from a feedlot presented with acute neurologic signs, characterized by circling, posterior weakness, and nonresponsiveness, followed by death. Histologically, the frontal lobe and the thalamus contained multiple foci of liquefaction that contained numerous degenerative neutrophils and foamy macrophages. Some of these foci were centered on blood vessels that contained fibrin thrombi and exhibited varying degrees of fibrinoid necrosis of the vessel wall. There was adjacent axonal degeneration and neuronal necrosis characterized by pronounced cytoplasmic eosinophilia, peripheralization of the nuclei, and loss of Nissl substance. Aerobic culture of the brain yielded moderate growth of Vibrio species, which was determined to be Vibrio cholerae by polymerase chain reaction analysis of a 438-base pair fragment of the 16 S ribosomal RNA gene. V. cholerae are motile, gram-negative, curved rod-shaped bacteria. Some strains of V. cholerae are important food- and water-borne bacterial pathogens that produce an often fatal diarrhea in humans. This is the first known case report of V. cholerae meningoencephalitis and cerebral abscessation in a bovine. 相似文献
70.
C.I. O''Connor-Robison MS B.D. Nielsen MS PhD R. Morris BS 《Journal of Equine Veterinary Science》2007,27(12):535-538
Six mature Arabian geldings were used in a two-period crossover study to investigate the effects of cellulase supplementation on fiber digestion. Horses were randomly assigned to either a control (CO; n = 3) or a cellulase (CE; n = 3) treatment for the first period and then treatments were switched for period 2. Each period consisted of a 10-day diet adaptation followed by a 3-day total fecal collection. The enzyme mixture contained 40,000 cellulase units/g and was fed at a rate of 3 g/day split evenly between two feedings. During the diet adaptation period, horses had ad libitum access to timothy hay and were also fed 165 g whole oats as a carrier for the supplement. When eating the CO treatment, horses consumed 16% more hay than when on the CE treatment (P = .004). Fecal output also tended to be greater when horses consumed the CO treatment as compared with CE treatment (P = .07). No differences were found between treatments for fecal percent dry matter (DM%), fecal neutral detergent fiber (NDF), fecal acid detergent fiber (ADF), fecal nitrogen (N), or fecal gross energy (GE). There was a trend for horses consuming the CO treatment to digest more NDF than when consuming the CE treatment (34.6% ± 1.5 vs 31% ± 1.5; P = .07). Horses also digested a greater %ADF, %N, and Mcal of energy when consuming the CO treatment than when consuming the CE treatment (P < .05). Cellulase addition to a hay-based horse diet decreased digestion of fiber components. 相似文献