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31.
Prof. Dr. D. Otto 《Journal of pest science》1997,70(2):30-33
The female sex pheromone ofL. decemlineata is an aphrodisiacum, switching on mating behaviour in contacting males. A biotest is described to estimate quantitatively the exciting power of a subject (female, isolated elytrae, glass dummy coated with extract) to males. The pheromone is present only in fertile females, also in freshly killed ones. It can be extracted by organic solvents. A dummy imitating a beetle's abdomen and contaminated with the residue of a female s wash solution is exciting to males too. Suitable solvents are ethylalcohol, acetonet, hexane. By this, the pheromone of 0,1 female is detectable. The residue can be taken up again with the same or an other solvent. The solution can be stored at ?18°C without significant losses, but at temperatures>+5°C their efficacy diminishes during 2 weeks. The exciting efficacy of the dry residue desreases to about 50% during nearly 4 weeks (at+22°C) or 9 weeks (at+5°C). The pheromone resists heating to about+160°C and is destroyed at higher temperatures. 相似文献
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Rhinoceros populations in Africa are under severe threat as a result of surging poaching rates and risk-mitigation strategies are continuously adapted in an attempt to ensure the survival of the species. This study compared faecal glucocorticoid metabolite (fGCM) levels of two age classes of limited free-ranging female white rhinos with fGCM levels of adult free-ranging female white rhinos. Subsequently, fGCM alterations in the limited free-ranging animals were monitored following routine dehorning as a measure of the animals’ short-term physiological stress response. Baseline fGCM levels differed significantly between tested groups, with both free-ranging and limited free-ranging adult animals showing significantly higher fGCM levels compared with limited free-ranging juvenile females. In contrast, baseline fGCM levels did not differ significantly between limited free-ranging and free-ranging adult individuals. Routine dehorning procedures resulted in a short-term stress response expressed by a significant increase in fGCM levels 48 h post-dehorning, with stress steroid levels returning to pre-dehorning concentrations 72 h after the procedure. 相似文献
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Cor triatrium dexter with Budd-Chiari syndrome and a review of ascites in young dogs 总被引:1,自引:0,他引:1
C. M. Otto M. Mahaffey C. Jacobs A. Binhazim 《The Journal of small animal practice》1990,31(8):385-389
Ascites with accumulation of a true or modified transudate, is relatively uncommon in young dogs. When it does occur, congenital defects of the cardiovascular, gastrointestinal, or renal systems, infectious diseases and trauma must be considered. Cor triatrium dexter, an abnormal membrane obstructing the caudal vena cava at the level of the right atrium, was diagnosed in an eight-month-old cocker spaniel presented with ascites. 相似文献
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Development and evaluation of a rapid absorbed enzyme immunoassay test for the diagnosis of Johne''s disease in cattle 总被引:8,自引:0,他引:8
An absorbed enzyme immunoassay (EIA) test for Johne's disease in cattle was developed in which absorption of cross-reacting antibodies occurred as a rapid reaction in solution rather than overnight with whole organisms and a subsequent centrifugation step. Total test time was reduced to less than 2 h with a minimum of manipulations. The test was evaluated in cattle herds from Johne's disease-endemic and Johne's disease-free regions of Australia. Specificity was 99.8%. Calculations of sensitivity were affected by the history of the herd under test. However, the EIA detected in excess of 80% of animals before onset of clinical disease and 65% of faecal shedders were EIA positive on, or before, first detection of Mycobacterium paratuberculosis in their faeces. The test should aid epidemiological studies and be a useful tool in the management and control of Johne's disease. 相似文献
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Strawberries were processed to juice, nectar, wine, and puree. For investigation of the antioxidant capacity as well as the contents of ascorbic acid, total phenolics and total anthocyanins, samples were taken after different stages of production to determine the effects of processing. The content of vitamin C was measured spectrophotometrically. The total phenolic content was analyzed by using the Folin-Ciocalteu method, and the amount of total anthocyanins was determined by using the pH-differential method. Two different methods-the trolox equivalent antioxidant capacity assay and the ferric reducing antioxidant power test-were used to determine the hydrophilic antioxidant capacity. This study showed the decrease of all investigated parameters within processing strawberries to different products. The content of ascorbic acid decreased with production time and processing steps, especially during heat treatment. The investigations on total phenolics in strawberry products proved fining to be a mild method to clarify berry juices and wines without removing high amounts of total phenolics. Fermentation did not lead to heavy losses of total phenolics, probably due to polymerization and condensation of monomer phenolics such as anthocyanins. Total anthocyanins and the hydrophilic antioxidant capacity decreased while using high temperatures. Anthocyanins also decreased considerably during the processing of wines, mainly caused by fermentation and pasteurization. 相似文献