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71.
张旭  冯琦胜  于惠  王玮  梁天刚 《草业科学》2011,28(4):648-655
甘南牧区不仅是我国重要的畜牧业生产基地,而且是黄河上游的重要水源涵养地.过牧超载导致天然草地退化,严重影响牧区的可持续发展.以甘南州玛曲县的阿孜畜牧试验场为例,分析了2008和2009年天然草地的可食牧草产量、放牧家畜承载量等方面的动态变化.研究结果表明,2009年阿孜畜牧试验场产草量有所增加,月均产草量较2008年提...  相似文献   
72.
鉴于细胞因子对乳房免疫机能独特有效的操纵和调节,在奶牛乳房炎控制中具有一定独特优势,作者就细胞因子的生物学活性、作用机制和特点进行了综述,并重点对国内外应用奶牛重组细胞因子防治奶牛乳房炎进行了总结、分析,有望为控制奶牛乳房炎提供安全、有效、实用的生物学防治途径。  相似文献   
73.
74.
研究了奶牛乳房炎发泡药剂的制备方法及其质量控制标准。该药剂是以碳酸氢钠和枸橼酸作发泡剂,研制药物的发泡量为原药液体积的8-12倍。经动物乳房给药试验证实,该药剂安全、无刺激性、在乳腺内分布效果明显优于常规剂型,室温保存有效期为2年。  相似文献   
75.
Peptide transporter 1 (PepT1) is a transporter responsible for absorbing dipeptide and tripeptide in enterocytes and is upregulated by dipeptide in mammals. It has not been certain whether intestinal PepT1 expression is responsive to dipeptides in chickens because of the lack of in vitro study using the cultured enterocytes. This study established a primary culture model of chicken intestinal epithelial cells (IECs) in two-dimensional monolayer culture using collagen gel by which the response of chicken PepT1 gene expression to dipeptide stimuli was evaluated. The cultured chicken IECs showed the epithelial-like morphology attached in a patch-manner and exhibited positive expression of cytokeratin and epithelial cadherin, specific marker proteins of epithelial cells. Moreover, the chicken IECs exhibited the gene expression of intestinal cell type-specific marker, villin1, mucin 2, and chromogranin A, suggesting that the cultured IECs were composed of enterocytes as well as goblet and enteroendocrine cells. PepT1 gene expression was significantly upregulated by synthetic dipeptide, glycyl-l-glutamine, in the cultured IECs. From the results, we herein suggested that dipeptide is a factor upregulating PepT1 gene expression in chicken IECs.  相似文献   
76.
Culling kangaroos, Australia’s most abundant marsupial, is a controversial practice in the Australian Capital Territory (ACT). The ACT government introduced a kangaroo management plan in response to the growing kangaroo population causing damage in grassland ecosystems. Although some groups (e.g., local government, some researchers) support implementation of this plan, critics claim it is inhumane and lacks concrete evidence. To examine media portrayal of this debate, this study conducted a content analysis of newspaper coverage between 2006 and 2016. Although ACT newspapers were impartial in their presentation of the debate, sources that previous studies found were typically considered trustworthy to speak on the scientific validity of the program were found to have conflicting messages and be less represented in the media. Thus, future research should explore if the messenger is more important than the message in determining influences on public perceptions about the use of lethal control.  相似文献   
77.
饲料安全隐患及对策   总被引:1,自引:0,他引:1  
饲料安全与食品安全密切相关.近年来,由饲料安全问题引发的食品安全事件屡见报道.笔者就影响饲料安全的主要问题进行了剖析,并提出改进措施.  相似文献   
78.
草地生态系统的保护及治理对策   总被引:11,自引:5,他引:11  
草地生态系统是以各种多年生草本占优势的生物群落与其环境构成的功能综合体,它是人类生存和发展的物质基础,也是人类可持续发展的重要前提.但是,由于人们不合理的利用草地,全世界的草地退化越来越严重,草地的退化不仅给生态环境造成了难以承受的压力,而且从健康、生存环境、生活质量方面给人类造成了严重的影响.笔者分析了草地生态系统的现状,并提出了草地生态系统的合理利用和保护方法及治理对策.  相似文献   
79.
In Uganda, control of vector-borne diseases is mainly in form of vector control, and chemotherapy. There have been reports that acaricides are being misused in the pastoralist systems in Uganda. This is because of the belief by scientists that intensive application of acaricide is uneconomical and unsustainable particularly in the indigenous cattle. The objective of this study was to investigate the strategies, rationale and effectiveness of vector-borne disease control by pastoralists. To systematically carry out these investigations, a combination of qualitative and quantitative research methods was used, in both the collection and the analysis of data. Cattle keepers were found to control tick-borne diseases (TBDs) mainly through spraying, in contrast with the control of trypanosomosis for which the main method of control was by chemotherapy. The majority of herders applied acaricides weekly and used an acaricide of lower strength than recommended by the manufacturers. They used very little acaricide wash, and spraying was preferred to dipping. Furthermore, pastoralists either treated sick animals themselves or did nothing at all, rather than using veterinary personnel. Oxytetracycline (OTC) was the drug commonly used in the treatment of TBDs. Nevertheless, although pastoralists may not have been following recommended practices in their control of ticks and tick-borne diseases, they were neither wasteful nor uneconomical and their methods appeared to be effective. Trypanosomosis was not a problem either in Sembabule or Mbarara district. Those who used trypanocides were found to use more drugs than were necessary.  相似文献   
80.
为探明黄芩(Scutellaria baicalensis Georgi)茎基部和根部灰霉病的病原菌,本文于2019—2021年春季对甘肃陇西县采集的黄芩病样进行病原菌的分离培养,运用形态学和内转录间隔区(Internal transcribed spacer, ITS)、甘油醛-3-磷酸脱氢酶(Glyceraldehyde-3-phosphate dehydrogenase,G3PDH)、热激蛋白60(Heat shock protein 60,HSP60)和RNA聚合酶亚基II(The second largest subunit of the nuclear RNA polymerase enzyme II,RPB2)多基因方法鉴定,采用菌丝生长抑制法进行药剂室内毒力测定和田间药剂防治试验。结果表明:引起黄芩灰霉病的病原菌为灰葡萄孢(Botrytis cinerea),春季发病时表现为地上部分枯死不发芽,靠近地表的根表面呈暗绿色水渍状,随后地下根木质部变软呈黄褐色腐烂,病健交界明显;室内毒力测定表明,97%咯菌腈对灰葡萄孢菌的抑菌作用最强,EC50为0.01...  相似文献   
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