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The Australian ruminant livestock industries are faced with the need to control parasitic infectious diseases that can seriously impact the health of animals. However, increasing levels of resistance to insecticides, anthelmintics and acaricides are substantially reducing the ability to control some of these parasites. Here we review the current situation with regard to chemical resistances in parasites across the various sectors of the Australian ruminant livestock industries and assess the level of threat that these resistances pose to the sustainability of these sectors in the short to long terms. We also look at the extent to which testing for resistance occurs across the various industry sectors, and hence how well-informed these sectors are of the extent of chemical resistance. We examine on-farm management practices, breeding of parasite-resistant animals, and non-chemical therapeutics that may act as short to long term means to reduce the current reliance on chemicals for parasite control. Finally, we look at the balance between the prevalence and magnitude of current resistances and the availability and adoption rates of management, breeding and therapeutic alternatives in order to assess the parasite control outlook for the various industry sectors.  相似文献   
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Journal of Plant Diseases and Protection - The nutritional quality of pollen was assessed measuring biomass and body size of freshly emerged, 1, 3, and 30 day old adult Amblyseius swirskii...  相似文献   
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The hydatid Limitation Program in Tasmania began in 1965 with the annual purging of dogs to identify areas of high prevalence of Echinococcus granulosus combined with a strong educational program aimed at preventing access to offal by dogs. From 1969 to 1975 aenia spp detected in dog purges were submitted for identification and changes in annual prevalences analysed for each species. Despite a significant reduction in the prevalence of E. granulosus since the beginning of the program, the control measures involved have apparently not predisposed to any significant change in the prevalence of T. ovis and T. hydatigena during the period of this survey.  相似文献   
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Summary The relative efficacy of 6 shower dip chemicals most frequently used for the treatment of sheep lice (Bovicola ovis) in Western Australia was examined. Groups of 20 sheep infested with lice were treated with products containing either alphamethrin, cyhalothrin, diazinon or diazinon plus piperonyl butoxide and rotenone, formulated as emulsifiable concentrates, and with products containing either coumaphos or magnesium fluorosilicate, formulated as wettable powders. All treatments were applied through a shower dip (Sunbeam model SSD). Inspections for lice were conducted until 9 months after dipping. No lice were found on sheep treated with the 4 emulsifiable concentrate products. In contrast, treatment with the wettable powders, which contained either coumaphos or magnesium fluorosilicate as the active ingredient, did not eradicate the lice infestations. The degree to which the fleece was wetted was assessed 20 minutes after dipping and showed that the wettable powder dips penetrated the fleece less than the emulsifiable concentrate dips. Less fluid was retained by wool staples in an in-vitro test when dip wash was made with the wettable powders. It was concluded that the degree of wetting attained at dipping was an important factor in achieving eradication of sheep lice.  相似文献   
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The purpose of this paper is to examine how regional manufacturing responds to a decline in manufacturing activity nationwide. A trivariate VAR model of the relationships between the Federal Reserve Board's Industrial Production Index for manufacturing, and two regional manufacturing output indexes is estimated. The regions considered correspond to the Fifth and the Seventh Federal Reserve Districts. A negative shock in the national index is imposed on the system to demonstrate the following: durations and general patterns of the impulse responses; severity of the responses in the two patterns; reaction times; and interregional differences in response patterns. The findings indicate that the response patterns generally differ between the regions.  相似文献   
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SUMMARY Lice were found in samples of baled wool from 198 of 464 flocks treated to eliminate an Infestation in the period July 1988 to June 1990. In 287 flocks the Insecticide was applied as a backline treatment and in 177 flocks a shower dip was used. Of these flocks, 41.5% and 44.6%, respectively, were found to be infested at the following shearing. After adjusting for the accuracy of the test, It was estimated that infestation in 2 consecutive 12-month periods occurred in 52.6% of flocks with a real incidence rate of 27.4%. Using these estimates, it was calculated that in 34.7% of infested flocks treatment did not kill all lice. There were no differences in the proportion of consecutive infestations between flocks treated with any of the 3 chemicals applied as backline treatments. Among flocks treated In a shower dip, 68.4% using coumaphos, 37.8% using diazlnon and 41.5% using cyhalothrin had consecutive Infestations (P < 0.05). The detection of lice in 63.2% of flocks that were treated with magnesium fluosilicate was, in part, attributed to the application of this chemical by one operator.  相似文献   
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