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101.
K. Marshall 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2014,131(5):329-340
Developing country livestock production systems are diverse and dynamic, and include those where existing indigenous breeds are currently optimal and likely to remain so, those where non‐indigenous breed types are already in common use, and systems that are changing, such as by intensification, where the introduction of new breed types represents significant opportunities. These include opportunities to improve the livelihood of the world's poor, increase food and nutrition security and enhance environmental sustainability. At present, very little research has focused on this issue, such that significant knowledge gaps in relation to breed‐change interventions remain. The purpose of this study is to raise awareness of this issue and suggests strategic research areas to begin filling these knowledge gaps. Such strategic research would include (i) assessing the impact of differing breed types in developing country livestock productions systems, from a range of viewpoints including intrahousehold livelihood benefit, food and nutrition security at different scales, and environmental sustainability; (ii) identification of specific livestock production systems within developing countries, and the type of livestock keepers within these system, that are most likely to benefit from new breed types; and (iii) identification of new breed types as candidates for in‐situ testing within these systems, such as through the use of spatial analysis to identify similar production environments combined with community acceptance studies. Results of these studies would primarily assist stakeholders in agriculture, including both policy makers and livestock keepers, to make informed decisions on the potential use of new breed types. 相似文献
102.
野生动物的行为是动物与环境相互作用的结果,动物园中动物的行为也反映出动物与相应的由人为提供的环境之间的关系。本文分析了现阶段在动物园圈养人工控制的环境下,动物展现出的有关动物行为如领域行为、攻击行为、交配行为、学习行为、摄食行为、警戒行为和体温调节行为等,以及由这些行为导致的安全问题,并有针对性地提出了在动物管理中相应的防范措施与解决办法。在动物园日常管理工作中,工作人员要熟知动物行为的目的与意义,观察动物行为,及时发现动物的不适与异常,充分掌握与安全有关的动物行为并及时分析,找出可能存在的对动物造成伤害的安全隐患,避免安全事故,给动物提供更舒适安全符合动物生物学特性的环境,同时也是提高动物福利的重要环节。 相似文献
103.
北美洲落基山脉纵贯加拿大西南和美国西北部,跨越北极带、寒带和温带高原气候带,是全球著名山脉之一。有奇特的高原地貌、世界最大的冰原、众多冰河、瀑布、高原湖泊、温泉及间歇喷泉等自然景观,以及多种植被、特有动物,每年吸引来自世界各地的众多游客。美国、加拿大政府和联合国教科文组织重视环保,在落基山脉建立众多国家公园,其中有7处划定为《世界遗产目录》《世界遗产公园》。国家公园重视环保,订立各种保育措施,值得借鉴。 相似文献
104.
105.
现阶段的化学药剂、抗生素、生物制剂等对动物疾病的防治容易引起药物残留和耐药性等问题,因此中草药制剂的研究日益受到人们的关注.文章就中草药防治动物疾病的作用特点、效果、应用等三方面进行了综述. 相似文献
106.
Malcolm P. Caulfield Heather Cambridge Susan F. Foster Paul D. McGreevy 《Veterinary journal (London, England : 1997)》2014,199(2):223-228
Recent investigations by the Australian Department of Agriculture, Fisheries and Forestry into high mortalities on live export voyages from Australia to the Middle East during the Northern hemisphere summer suggest that animal welfare may be compromised by heat stress. The live export industry has generated a computer model that aims to assess the risk of heat stress and to contain mortality levels on live export ships below certain arbitrary limits. Although the model must be complied with under Australian law, it is not currently available for independent scientific scrutiny, and there is concern that model and the mandated space allowances are inadequate. This review appraises the relevant literature on heat stress in sheep and cattle, including laboratory studies aimed at mimicking the ambient temperatures and humidity levels likely to be encountered on live export voyages. Animal welfare is likely to be very poor as a result of heat stress in some shipments. 相似文献
107.
为了全方面地进行课程改革,使课程改革取得更好的效果,金华职业技术学院主要从理论考核、实践考核以及结合适当的论文写作等三方面入手,针对《动物寄生虫》课程考核方式的改革进行了探讨,以期更好地服务于课程全面改革的实践。 相似文献
108.
Ole Bent Samuelsen Arne Ervik Lise Torkildsen Øivind Bergh 《Aquaculture International》2002,10(3):257-264
In this investigation, the efficacy of a single intraperitonealinjection of either flumequine or oxytetracycline hydrochloride to preventoutbreak of atypical Aeromonas salmonicida infection ingoldsinny wrasse, Ctenolabrus rupestris, following stresswas studied. Six groups of goldsinny wrasse, each of 50 individuals, weretreated with an intraperitoneal injection of either propylene glycol : saline(50 : 50), 200 mg kg–1 of oxytetracycline or 50mg kg–1 of flumequine dissolved in propyleneglycol : saline (50 : 50). Three days following medication the fish in allgroups were stressed by an intraperitoneal injection of prednisolone acetate(0.05 ml) and a rise in seawater temperature from 9 to 11°C. Mortality was observed daily for 21 days. Flumequine wasthe more effective with a mean cumulative mortality of 5% compared tooxytetracycline with 54%. The mean cumulative mortality in the unmedicatedcontrol groups was 84%. Bacterial examination of kidneys from dead fishconfirmed the presence of atypical A. salmonicida as theprobable cause of death. Minimum inhibitory concentration (MIC) values forflumequine and oxytetracycline against the isolated A.salmonicida were determined to 0.13 gml–1, and 2.0 g ml–1,respectively. 相似文献
109.
针对当前鄂州市鄂城区园林绿化的现状,调查了鄂城区150多种常见树种病虫害发生情况,如香樟、法国梧桐、广玉兰、栾树、合欢、垂柳、银杏、桂花、法国冬青、红继木、雪松、大叶黄杨、小叶女贞、梅花、碧桃、垂柳等,并提出了相应的防治措施,以供园林绿化工作者参考。 相似文献
110.