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11.
Cochliomyia hominivorax (Calliphoridae) is one of the most important myiasis-causing flies and is responsible for severe economic losses to the livestock industry throughout the Neotropical region. In Brazil, C. hominivorax has been controlled mainly with organophosphate (OP) insecticides, although the inappropriate use of these chemicals can result in the selection of resistant flies. Changes in carboxylesterase activity have been associated with OP insecticides in some arthopodan species. In this work, we isolated and characterized part of the E3 gene in C. hominivorax (ChE7), which contained the same substitutions responsible for the acquisition of OP hydrolase activity in Lucilia cuprina (Calliphoridae). Digestion of the polymerase chain reaction products with a restriction enzyme that specifically recognized the mutation site unambiguously differentiated wild and mutated esterase alleles. The PCR-RFLP assay therefore provided a fast, reliable DNA-based method for identifying C. hominivorax individuals with a mutation in the esterase gene. Further bioassays to determine the association of this mutation with OP resistance in C. hominivorax should allow the development of more effective strategies for managing this species.  相似文献   
12.
对咸阳地区的畜禽养殖状况,畜禽粪便的污染程度,畜禽粪便治理的现状与存在的问题,提出了治理的措施及治理后的前景,以期为政府部门在研究制定咸阳市规范时提供考虑。  相似文献   
13.
Previous research has generally not found a strong relationship between participation in outdoor recreation and environmental concern. Research has suggested, however, that the motivation underlying recreation can mediate this relationship for some nature-based recreation groups. We hypothesized that the motivation underlying participation in birding mediates the participation–environmental concern relationship. We collected data via mail-back surveys from 529 American Birding Association members. Using structural modeling, we compared a direct effects model with partial and full mediation models with motivation variables as the mediators. The partial mediation model was weakly supported for two out of three motivation variables. Fit indices showed all models to have less than adequate fit. The results suggested that participation may not lead to environmental concern and that other variables, including motivation, may be more influential.  相似文献   
14.
青海肉羊业生产现状及发展对策   总被引:3,自引:0,他引:3  
杨葆春 《青海草业》2008,17(1):19-23
针对国内外及青海省肉羊业生产现状和发展趋势,分析了青海省发展肉羊业的有利条件和存在的问题,并从加强对发展肉羊业的组织领导、建立肉羊良种繁育体系、大力开展经济杂交,实现商品肉羊杂交化、组织肥羔生产、加快畜群周转、加大草原建设和饲草料基地建设、培育“龙头企业”、注重肉羊生产加工环节的无公害化、落实疫病虫防治检疫制度等方面,对发展青海肉羊业生产提出了对策。  相似文献   
15.
抗旱耐热白三叶新品种选育初报   总被引:5,自引:0,他引:5  
鄂牧一号白三叶是以美国瑞加和路易斯安那两个白三叶品种为原始材料,经单株抗性造反份系比较鉴定,多系混合杂交,品种比较和区域试验选育而成,历时10年。该品种具有高产,抗旱,耐热和粗蛋白含量高等特性,是南方低山丘陵地区有推广应用前景的优良牧草和草坪植物。  相似文献   
16.
为了探讨不同饲料添加剂水平的饲粮对新西兰白兔生产性能的影响,试验采用加日龄健康新西兰白兔,按性别对等原则分成4组,试验期为12周.对照组只饲喂基础饲粮,试验Ⅰ组饲粮中加入适量营养型物质.试验Ⅱ组为中草药添加剂组,试验Ⅲ组为酶制剂、营养型物质和中药添加剂组.测定第3、5、8周各组新西兰白兔的体重、体长和胸围.12周后屠宰,测定其相关生产性能指标,并统计饲料报酬和成活率.结果表明,试验Ⅲ组各项生产性能指标明显高于对照组,且差异显著(P<0.05);与试验Ⅰ组、试验Ⅱ组相比各项指标略高,但差异不显著(P>0.05).表明营养型物质、中草药添加剂以及酶制剂在基础饲粮中的适量添加对新西兰白兔的生产性能有明显的促进作用.  相似文献   
17.
AIMS: To determine current practices and attitudes towards vaccination of dogs and cats of veterinarians in New Zealand; the methods used for informing clients on which vaccines to use, and the preferred site for vaccination of cats.

METHODS: A postal questionnaire was sent to all 483 listed veterinary practices in New Zealand during February 2012. Some questions were specific to pet dogs, cats, or working farm dogs. Responses were categorised according to practice type and geographical region of the respondent. Factors associated with respondent recommendation of annual vaccination with modified live viral (MLV) vaccines were examined using logistic regression analysis. Vaccines that were considered to be essential for every animal were defined as core; those that may be recommended for animals whose location or lifestyle placed them at risk, were defined as non-core.

RESULTS: There were 204 useable returns, equivalent to a response rate of 42.2%, distributed across the country. Annual vaccination with MLV vaccines of dogs was recommended by 54/198 (27.3%) respondents, and of cats by 107/181 (59.1%) respondents. Factors associated with the recommendation of annual administration of MLV vaccines to dogs included being a companion animal practice, a desire for policies on vaccination to be left to individual clinics, and having one veterinarian in the practice. Administration of the final vaccination for puppies was recommended at ≥14 weeks old by 55/185 (29.7%) respondents, and for kittens at ≥13 weeks old by 42/183 (23%) respondents. Of respondents that administered MLV vaccines annually, 62/103 (60.2%) believed reducing the frequency of vaccination would reduce income, and 52/103 (50.5%) considered it would have a negative effect on animal health. Advice to enable clients to decide which non-core vaccines were administered was given by 181/199 (91%) respondents. Factors considered when recommending a vaccine included consideration of risk to individual patients (190/203; 93.6%), requirements of boarding kennels/catteries (165/203; 81.3%) and clinic vaccination policy (142/203; 70%). The preferred site for administering MLV vaccines to cats was the dorsal neck or inter-scapular region (137/198; 69.2%). Amongst respondents, 18 wanted disease surveillance information to allow for truly informed decisions to be made about vaccination.

CONCLUSIONS AND CLINICAL RELEVANCE: Veterinarians can now compare their own vaccination practices and attitudes with those of veterinarians nationally, and internationally. There is a need for national surveillance information and for continued education of the public and commercial kennel and cattery owners for optimal vaccination strategies to be developed.  相似文献   

18.
兽药行业的现状与发展展望   总被引:2,自引:3,他引:2  
从生产能力、企业数量、新药研发评审等总结了国内外兽药行业的现状,并对国内兽药生产企业的研发工作提出了展望。  相似文献   
19.
王宁娟 《中国饲料》2021,1(6):131-134
随着关键词结构性改革政策的不断推进,以及我国环保压力的不断增强,饲料行业面临着前所未有的挑战.本文以我国饲料行业为研究对象,进一步分析当前我国饲料行业的经济现状,深度挖掘目前行业的发展情况、市场宏观环境和政策背景等,并对比我国饲料行业与其他国家饲料行业的发展情况,得出目前我国饲料行业的发展困境.营销模式是企业经营发展的...  相似文献   
20.
调查以商丘地区的养殖企业为主,旨在了解近年来商丘地区畜牧业发展状况及存在的问题.结果显示:河南省商丘地区的畜牧业因其独到的地理位置,依托资源优势,主要以猪、牛、羊等动物的养殖为主,且有规模不同的饲养方式,养殖数量呈逐年递增趋势(2006,2007,2008年);养殖业存在发展资金不足、品种良种化程度低、饲料资源和种类单一、生态健康养殖理念缺乏等问题,并提出相应的解决方案和措施.  相似文献   
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