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排序方式: 共有494条查询结果,搜索用时 15 毫秒
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2005 Guidelines for the diagnosis, prevention and management of heartworm (Dirofilaria immitis) infection in dogs 总被引:2,自引:0,他引:2
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Holdsworth PA Vercruysse J Rehbein S Peter RJ De Bruin C Letonja T Green P;World Association for the Advancement of Veterinary Parasitology 《Veterinary parasitology》2006,136(1):3-13
These guidelines have been prepared to assist in the planning, conduct and interpretation of studies for the assessment of the efficacy of ectoparasiticides (excluding repellents) against the biting and nuisance dipteran flies of ruminants. Information is provided on the selection of animals, dose determination and dose confirmation studies, field studies, record keeping and result interpretation. These guidelines advocate the use of pen facilities for dose determination and dose confirmation studies. These guidelines also are intended to assist investigators on how to conduct specific studies, to provide specific information for registration authorities involved in the decision-making process, to assist in the approval and registration of new ectoparasiticides, and to facilitate the worldwide adoption of standard procedures. 相似文献
75.
The breeding of wild animals for commercial purposes is becoming more frequent nowadays. This situation has led to an increase
in contact rates between wild and domestic animals, with subsequent reciprocal transmission of parasites. In this study, we
characterized the gastrointestinal and blood parasites of a group of 15 semi-captive guanacos (Lama guanicoe). We characterized gastrointestinal parasites by analyzing fecal samples through the sedimentation–flotation technique and
hemoparasites by using blood smears stained with Giemsa. We found several gastrointestinal parasites including Nematoda and
protozoans. The most frequently found parasites were Nematodirus sp. and Eimeria sp. In contrast with previous studies, neither Cestoda nor Fasciola were found. The only hemoparasite detected was Mycoplasma haemolamae, a parasite already described in llamas and alpacas. We conclude that the most frequent gastrointestinal parasites of semi-captive
guanacos were nematodes and protozoans. Also, the hemoparasite M. haemolamae seems to be prevalent among captive populations of South American camelids. Finally, captive guanacos share several parasites
with the traditional livestock. Therefore, keeping captive or semi-captive guanacos without an adequate sanitary protocol
might have adverse consequences to adjacent traditional cattle farming and/or for wild animals. 相似文献
76.
培训考察团先后访问了美国联邦国有林管理局、美国南部林区(第八区)国有林管理分局、西南林区(第五区)安吉斯林管区和乔治亚州农业厅以及私有林主。美国森林资源丰富,国有林垂直管理体制简单高效,森林经营科学规范。比较了中美两国国有林管理方面的主要差异,分析了我国重点国有林区管理体制存在的问题,以期为我国国有林管理体制改革提供借鉴。 相似文献
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J.W. Kijas M. Serrano R. McCulloch Y. Li J. Salces Ortiz J.H. Calvo M.D. Pérez‐Guzmán The International Sheep Genomics Consortium 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2013,130(6):468-475
Most published genomewide association studies (GWAS) in sheep have investigated recessively inherited monogenic traits. The objective here was to assess the feasibility of performing GWAS for a dominant trait for which the genetic basis was already known. A total of 42 Manchega and Rasa Aragonesa sheep that segregate solid black or white coat pigmentation were genotyped using the SNP50 BeadChip. Previous analysis in Manchegas demonstrated a complete association between the pigmentation trait and alleles of the MC1R gene, setting an a priori expectation for GWAS. Multiple methods were used to identify and quantify the strength of population substructure between black and white animals, before allelic association testing was performed for 49 034 SNPs. Following correction for substructure, GWAS identified the most strongly associated SNP (s26449) was also the closest to the MC1R gene. The finding was strongly supported by the permutation tree‐based random forest (RF) analysis. Importantly, GWAS identified unlinked SNP with only slightly lower p‐values than for s26449. Random forest analysis indicated these were false positives, suggesting interpretation based on both approaches was beneficial. The results indicate that a combined analytical approach can be successful in studies where a modest number of animals are available and substantial population stratification exists. 相似文献
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