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201.
The pink bollworm (PBW), Pectinophora gossypiella (Saunders) (Lepidoptera: Gelechiidae), is the key pest in cotton (Gossypium spp.) production areas in the southwestern United States and in many other cotton-producing areas of the world. The high costs of chemical control, continuing economic losses, secondary pest problems and environmental considerations suggest the need for ecologically oriented PBW management strategies. Extensive research has resulted in a broad array of monitoring, biological control, cultural, behavioural, genetic and host plant resistance methods that can serve as a base for the formulation of integrated PBW management systems. The life history characteristics of the PBW, in particular the high mobility of adults, indicate the need for combinations of selected integrated pest management (IPM) components implemented over large geographical areas. The areas involved present a wide range of PBW population densities, differences in cotton production methods and social and environmental considerations. The best option is tailor-made systems for targeted management areas with the selection of IPM components based on the PBW population density, crop production methods and economic feasibility. The unlikelihood of eradication indicates the need for long-term monitoring and programme maintenance following successful area-wide management. The success of area-wide PBW management is highly dependent on participation in the planning, site selection, implementation and assessment phases of the programme by all segments of the agricultural community. A highly effective extension--education communication programme is an essential component. Local uncoordinated efforts have not reduced the economic status of this pest in any area where it is an established pest. The potential long-term benefits of PBW population suppression on an area-wide basis appear to justify area-wide efforts in terms of reduced costs, more effective control, less environmental contamination and other peripheral problems associated with conventional control approaches. 相似文献
202.
Objective To determine the extent of the snake bite problem in domestic animals, its regional significance and the effects of antivenom treatment.
Design A questionnaire was designed seeking information on the number and type of domestic animals referred, whether treated or untreated, type of snakes and management of the bite.
Procedure The survey form was sent to 10% of veterinary surgeons, selected at random throughout Australia.
Results The response of 106 veterinary surgeons revealed that snake bite in domestic animals is frequent, with an estimated 6200 cases reported annually. Bites were more prominent in rural (78%) than urban areas (22%) with brown, tiger and black snakes accounting for 76%, 13% and 6% of cases, respectively. Cats and dogs were the most frequently reported victims. Ninety-one percent of cats and 75% of dogs survived following the administration of antivenom whereas 66% of cats and 31% of dogs survived without antivenom. Overall, in 33% of cases antivenom was not used, and venom detection kits were used in only 1% of cases. A number of drugs were used in various combinations with or without antivenom and intravenous fluids in the treatment of animals with snake bite, but their role in reducing the severity of envenomations was not assessed.
Clinical implications Antivenom significantly improves the chances of survival of domestic animals bitten by snakes. 相似文献
Design A questionnaire was designed seeking information on the number and type of domestic animals referred, whether treated or untreated, type of snakes and management of the bite.
Procedure The survey form was sent to 10% of veterinary surgeons, selected at random throughout Australia.
Results The response of 106 veterinary surgeons revealed that snake bite in domestic animals is frequent, with an estimated 6200 cases reported annually. Bites were more prominent in rural (78%) than urban areas (22%) with brown, tiger and black snakes accounting for 76%, 13% and 6% of cases, respectively. Cats and dogs were the most frequently reported victims. Ninety-one percent of cats and 75% of dogs survived following the administration of antivenom whereas 66% of cats and 31% of dogs survived without antivenom. Overall, in 33% of cases antivenom was not used, and venom detection kits were used in only 1% of cases. A number of drugs were used in various combinations with or without antivenom and intravenous fluids in the treatment of animals with snake bite, but their role in reducing the severity of envenomations was not assessed.
Clinical implications Antivenom significantly improves the chances of survival of domestic animals bitten by snakes. 相似文献
203.
Lyctia Zepeda Kenneth L. Buelow Kenneth V. Nordlund chester B. Thomas Michael T. Collins William J. Goodger 《Preventive veterinary medicine》1998,33(1-4):183-193
We used a linear programming model to estimate the financial returns to a Staphylococcus aureus testing and control program over a 1-year period for a 100-cow herd, with a 8636-kg rolling-herd average. Six tests, which vary in sensitivity from 0.80 to 0.98 and specificity of 0.99, were examined in simulated herds with 10, 20 and 30% prevalence of S. aureus infection. Sensitivity of these results to a range of assumptions regarding rolling-herd average, milk price, somatic cell-count premium, and cost and cure rate of dry treatment were examined to determine the profits from the program. The profits of a control program are most dependent upon prevalence, cell-count premium, and cost of dry treatment. In our simulation for a 100-cow herd, a testing and control program appears to cost less than US$10 per cow per year, and pays for itself within 1 yr, except under the lowest prevalence and most-adverse conditions (low yield, high cost of dry treatment, or low SCC premium). 相似文献
204.
Hereditary nephritis in the bull terrier: evidence for inheritance by an autosomal dominant gene 总被引:2,自引:0,他引:2
J C Hood W F Robinson C R Huxtable J S Bradley R J Sutherland M A Thomas 《The Veterinary record》1990,126(18):456-459
A high prevalence of renal failure has been reported in bull terriers in Australia. The pattern of inheritance was analysed in a family of 33 bull terriers in which 10 dogs had renal disease manifested by proteinuria, ultrastructural abnormalities in the glomerular basement membrane, renal failure, or 'end stage' kidneys. The presence of at least one affected parent for each affected offspring, the approximately equal male/female ratio and the apparent absence of 'generation-skipping', strongly supported an autosomal dominant mode of inheritance, assuming a fully penetrant single major gene locus. Further evidence was not compatible with either an autosomal recessive or X-linked inheritance pattern. This contrasts with the X-linked inheritance shown in Alport's-type human hereditary nephritis and hereditary glomerulopathy in the samoyeds. Hereditary nephritis in the bull terrier should be a useful model for non-Alport's-type human hereditary nephritis, which is also reported to have an autosomal dominant inheritance pattern. 相似文献
205.
Phase II Clinical Trial of Carboplatin in Canine Transitional Cell Carcinoma of the Urinary Bladder 总被引:4,自引:3,他引:1
Ruthanne Chun Deborah W. Knapp William R. Widmer Dennis B. DelNicola Nita W. Glickman Thomas Kuczek Amalia Degortari Connie M. Han 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1997,11(5):279-283
Fourteen dogs with histologically-confirmed transitional cell carcinoma (TCC) of the urinary bladder were treated with 300 mg/m2 carboplatin every 3 weeks. Response to therapy was assessed with abdominal radiography, double contrast cystography, urinary bladder ultrasonography and thoracic radiography before therapy and at 6–week intervals during therapy. Dogs were monitored for hematologic toxicity with a CBC and platelet count performed immediately before and 10 to 14 days after carboplatin treatment. Tumor responses included progressive disease in 11 dogs and stable disease in 1 dog. Two dogs were euthanized due to carboplatin toxicity before assessment of tumor response. Toxicity included thrombocytopenia with or without neutropenia in 7 dogs and gastrointestinal toxicity in 6 dogs. Carboplatin therapy was not beneficial in the treatment of TCC in the 14 dogs in this study. 相似文献
206.
Five strains of Mycoplasma gallisepticum (MG) were examined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and Western blot analysis for the presence of carbohydrate-containing components. Staining with periodic acid-Schiff (PAS) demonstrated carbohydrate components in three of the five strains studied. The PAS-reactive bands counterstained for protein, indicating a possible glycoprotein nature. Western blot analysis using three biotinylated lectin probes demonstrated the presence of additional glycoconjugates in the blot profiles of each MG strain. The carbohydrate specificity of lectin binding was demonstrated by competition experiments using specific sugars. Differences in the number, electrophoretic mobility and the morphology of PAS and lectin reactive bands were reproducible among separate preparations of each MG strain. These findings indicate substantial phenotypic diversity among the five MG strains in their ability to produce or acquire glycoconjugates. 相似文献
207.
D Sisson G Dilling M M Wong W P Thomas 《American journal of veterinary research》1985,46(7):1529-1533
Ninety dogs naturally infected with Dirofilaria immitis and 103 noninfected dogs, as determined by necropsy, were used to compare the sensitivity and specificity of the cuticular and somatic reactions of the indirect fluorescent antibody test (IFA-C and IFA-S, respectively) and 2 enzyme-linked immunosorbent assays (ELISA). In microfilaremic and amicrofilaremic heartworm-infected dogs, negative results were common for all serotests. In dogs without adult heartworms at necropsy, 32% to 49% were positive, using 1 ELISA, 27% to 29% were positive with the other ELISA, 15% to 36% were positive with the IFA-S, and 0% to 1% were positive using the IFA-C, depending on the classification of borderline reactions. The prevalence of false positive serotests was probably not due to the detection of precardial stages of D immitis in dogs obtained from areas of low endemicity. Until the causes of the false-positive tests are resolved, the use of currently available serotests for routine diagnostic screening or as criteria for instituting treatment is not recommended. 相似文献
208.
The effect of foliar application of cytokinin (benzyl-adenine, 150 mg L−1) and gibberellin (GA4 + GA7, 150 mg L−1) on growth and flower development of 5-year-old plants of two jojoba clones was studied. The plant growth regulators were applied on October 5, 1999 (spring) and the plants were evaluated 120, 240 and 360 days after application. Shoot length, total number of nodes and number of nodes with branching were statistically different between clones but not between the growth regulator treatments.The total number of flowers on both clones was significantly increased by treatment with benzyl-adenine (BA) and significantly reduced by treatment with gibberellin. The seed yields, evaluated 180 days after application, were not statistically different from the control due to an increase in flower abortion. One clone treated with gibberellin showed a significant decrease in number and weight of seeds, the other did not.Histology of axillary buds revealed that BA application on one clone (4.11.32) enlarged the flower meristem, differentiating multiple flower production. 相似文献
209.
210.