浅谈影响蛋壳强度的因素

在养鸡业中,由于蛋壳破损或渗漏而不能出售或降价出售的鸡蛋往往造成巨大的经济损失。蛋壳作为蛋的一种天然包装,不仅便于保存、运输、对成长中的胚胎提供钙质,帮助胚胎骨骼钙化,同时它作为一个多孔的保护壳也便于孵化。     

河西地区农户规模养蛋鸡经济效益调查

河西地区是我省商品粮基地,饲料资源相对充足,鸡产品市场潜力很大,加之交通便利,流通活跃,养鸡业实现规模化、区域化发展条件理想,组装配套适度规模养鸡生产技术及饲养模式,对引导该地区养鸡业稳步发展,增加养鸡业抵御市场风险的能力和提高养鸡业的经济效益具有重要意义.为此,我们于1999年～2001年开展了“河西地区农户规模养鸡技术试验示范”项目,项目实施期间我们对项目区部分规模养蛋鸡户经济效益进行了调查,现报告如下:     

浅谈规模化养鸡场疫病流行特点和防治策略

<正>近几年来,随着集约化养鸡业的迅速发展,特别是规模化养鸡场的大量兴起,鸡的各种传染病、寄生虫病危害日趋突出,给养鸡业造成了严重的经济损失,成为制约养鸡业发展的"瓶颈"。因     

鸡常见传染病防制

随着社会发展,鸡的饲养量不断增加,饲养规模不断扩大,然而鸡的各种疾病严重影响养鸡业的发展,特别是鸡的传染病发病率高,造成的危害大。因此,掌握鸡传染病的基本知识和防治技术,对阻止鸡传染病的发生和流行、提高产品质量、保障人民身体健康,促进养鸡业发展,都具有十分重要的意义。文章综述了鸡传染病的防制。     

伊犁地区养鸡业疫病防控存在的问题及对策

近年来,鸡蛋、鸡肉已成为人们餐桌上的常见食品,这极大刺激了养鸡业的进步和规模扩大,存在的疫病防控问题又阻碍了其发展。详细介绍了养鸡业疫病防控体系,希望对提高养鸡业疫病防控工作的质量有所帮助。     

微生态制剂在白羽肉鸡生产中应用与注意事项

白羽肉鸡腹泻病如大肠杆菌病、厌氧菌、沙门氏菌病等常见多发病,每年给养鸡业造成很大的经济损失。使用微生态制剂防治白羽肉鸡腹泻病,无污染、无药殘、无耐药性,对降低发病率、死亡率、提高饲料利用率作用明显。文章就微生态制剂在白羽肉鸡生产中的作用及注意事项作一个简要概述。     

鸡五种重大疫病的防疫措施

<正>在养鸡业中,严重危害鸡的重大疫病主要有高致病性禽流感、新城疫、传染性法氏囊病、马立克氏病、J亚群禽白血病等五种重大传染病。在发展养鸡业时,必须认真应对这五种重大传染病的危害,了解它的流行特点和传播规律,掌握这五种传染病的防疫技术,彻底消除重大疫病对养鸡业的危害,把风险系数降到最低,提高养鸡的成功率。     

中草药防治鸡球虫的最新研究进展

鸡球虫病是严重危害养鸡业的寄生虫病之一。在防治该病时,化学药物由于毒副作用大、药物残留等缺陷而越来越不被人认可,而中草药以成本低、使用安全、无毒副作用得到许多研究学者的青睐。文章主要综述了中草药在防治鸡球虫病的应用及其作用机理。     

养鸡场常见细菌性疾病防控

近年养鸡业趋向于集约化、密集型的饲养,这也是养殖业发展的必然趋势。然而鸡的各种疾病严重影响养鸡业的发展,造成的危害大。文章综述了鸡常见细菌性疾病的诊治和防控。     

鸡常见寄生虫病的诊疗与防治

在市场经济推动下，畜牧业不断壮大与发展，养鸡业已成为畜牧业中的支柱性产业，人们对优质鸡产品的需求量逐年上升。然而，鸡群疫病的发生仍是阻碍养鸡业发展的重要因素。鸡寄生虫病是养鸡业中较为常见的一种疾病，具有潜伏期长、临床症状不典型、危害严重的特性。基于此，阐述了鸡寄生虫病的危害，综合探讨了鸡寄生虫病的诊疗与防治，以期为减少鸡寄生虫病的发生提供相关理论依据。     

伊犁地区雏鸡群沙门氏菌病的分离及病菌药物敏感性的调查

选择发病雏鸡群作为调查对象,研究伊犁地区鸡群中沙门氏菌病的流行情况。实验共调查发病鸡群23个,分别分布在伊犁地区的3个县城和5个乡镇,分出沙门氏菌的鸡群为20个。对这些沙门氏菌株,选用圆纸片扩散实验法(Kirby-Baueer Disc Diffusion)作药敏实验,结果所实验的12种药物中,丁胺卡那、头孢噻肟、氧氟沙星和利福平等药表现出较好的抑菌杀菌效果,但是所有实验沙门氏菌都有耐药现象存在。     

雏鸡白痢沙门氏菌病的诊断与防控

为了更有效的防控雏鸡白痢沙门氏菌病,笔者调查了西昌市某养鸡户病鸡的临床症状和剖检病理变化,对病原菌进行了分离鉴定,并根据药敏试验结果选用病原菌高敏的药物对病鸡进行治疗。结果表明,该病为雏鸡白痢沙门氏菌病,使用病原菌敏感的药物灵先锋及拜诺欣对病鸡进行治疗效果显著。此外,笔者还提出了该病的综合防控措施,对减少该病的发生和减少经济损失均具有较大的价值。     

后危机时代中国粮食对外贸易的政策选择

中国在2007～2008年的国际粮食危机中没有受到冲击，主要原因是中国已经建立了较为健全的粮食安全系统，具有较低的粮食对外贸易依存度。但仍存在着一些制约粮食安全的因素和隐患，中国利用国际粮食市场虽然在经济上具有可行性，但是国际粮源的可供性、政治上的可靠性、国际规则的有效性都难以保障。因此坚持95％的粮食基本自给政策，实施“宽进严出”策略，完善粮食贸易管理措施，实施粮食进口贸易伙伴国的多元化，就成为中国粮食对外贸易政策的基本选择。     

中药在现代畜牧业中的应用

目的:了解中药在现代畜牧业中的应用现状。方法:参阅了大量相关文献,对近年来中药在现代畜牧业中的应用进展作一综述。结果:中药在免疫功能调节、抗病原体、抗炎作用、抗应激作用等方面研究较多,具有很好的应用前景。结论:随着人们对"绿色农业"的渴求和向往,中药在畜牧业中的应用将具有广泛的开发前景。     

Marine fisheries and future ocean conflict

Conflict over marine fishery resources is a growing security concern. Experts expect that global changes in our climate, food systems and oceans may spark or exacerbate resource conflicts. An initial scan of 803 relevant papers and subsequent intensive review of 31 fisheries conflict studies, focused on subnational and international conflicts, suggests that four substantial scientific gaps need addressing to improve our understanding of the nature and drivers of fisheries conflict. First, fisheries conflict and levels of conflict intensity are not precisely defined. Second, complex adaptive systems thinking is underutilized but has the potential to produce more realistic causal models of fishery conflict. Third, comparative large‐scale data and suitably integrative methodologies are lacking, underscoring the need for a standardized and comparable database of fisheries conflict cases to aid extrapolation beyond single case‐studies. Fourth, there is room for a more widespread application of higher order concepts and associated terminology. Importantly, the four gaps highlight the homogenized nature of current methodological and theoretical approaches to understanding fishery conflict, which potentially presents us with an oversimplified understanding of these conflicts. A more nuanced understanding of the complex and dynamic nature of fishery conflict and its causes is not only scientifically critical, but increasingly relevant for policymakers and practitioners in this turbulent world.     

Characterization of the trade in manta and devil ray gill plates in China and South‐east Asia through trader surveys

相似文献   

Collateral damage? Small‐scale fisheries in the global fight against IUU fishing

Concern over illegal, unreported and unregulated (IUU) fishing has led to a number of policy, trade and surveillance measures. While much attention has been given to the impact of IUU regulation on industrial fleets, recognition of the distinct impacts on small‐scale fisheries is conspicuously lacking from the policy and research debate. In this paper, we outline three ways in which the application of IUU discourse and regulation undermines small‐scale fisheries. First, the mainstream construction of “illegal,” “unreported” and “unregulated” fishing, and also the categorical use of “IUU” in an all‐inclusive sense, disregards the diversity, legitimacy and sustainability of small‐scale fisheries practices and their governing systems. Second, we explore how the recent trade‐related measures to counter IUU fishing mask and reinforce existing inequalities between different sectors and countries, creating an unfair burden on small‐scale fisheries and countries who depend on them. Third, as IUU fishing is increasingly approached as “organized crime,” there is a risk of inappropriately targeting small‐scale fisheries, at times violently. Reflecting on these three trends, we propose three strategies by which a more sensitive and ultimately more equitable incorporation of small‐scale fisheries can be supported in the global fight against IUU fishing.     

Catch and trade bans for seahorses can be negated by non-selective fisheries

1. All seahorse species (genus Hippocampus) are listed under Schedule I of India's Wild Life Protection Act, making all capture and trade of seahorses illegal. In the more than 15 years since the ban, little work has been done to assess its effects on seahorse conservation.
2. Between 2015 and 2017, fisheries and trade surveys were conducted along the south-east coast of India, in the state of Tamil Nadu, historically known to be a hub for seahorse catches and trade.
3. Seahorses were primarily landed as bycatch, although in greater quantities by traditional drag nets than as trawl bycatch. Total annual catches were estimated between 4.98 million and 13.64 million seahorses, 87% of which were caught by active non-selective gear.
4. Generalized additive models revealed that seahorse catch per unit effort had non-linear relations with depth and latitude, and were higher in biogenic habitats, with active, bottom-used, and non-selective gears (e.g. trawls).
5. The illegal nature of the trade in seahorses hampered an understanding of trade routes and trade volumes. Catch estimates indicated that 11.21–30.31 tonnes of seahorses probably entered trade, yet interviews with traders only documented trade of about 1.6 tonnes.
6. Fishers reported a decreasing availability of seahorses. Since most seahorses come from bycatch in persistent fisheries that are not directly affected by the ban on seahorse capture, this decline is likely to represent a population decline.
7. A fishery and trade ban for incidentally caught species, particularly in a poorly regulated fishery, appears to add little conservation value. There needs to be a shift in the management approach, moving from a ban towards spatial and temporal restrictions, and toward enforcing existing fishery regulations.

     

Fisheries,large‐scale trade,and conservation of seahorses in Malaysia and Thailand

• 1. All seahorse species (genus Hippocampus) are listed under CITES Appendix II, requiring that exports of these fishes must be regulated for sustainability. Preliminary trade surveys and anecdotal reports suggested Malaysia and Thailand represented an important source for seahorses used globally in traditional medicine, curios, and aquarium display, but few historic trade or fisheries data are available. Baseline information about pre‐CITES catch and trade is essential for managing seahorse fisheries and trade under CITES, and for understanding present‐day effects of CITES regulation on the seahorse trade.
• 2. In 1998–1999, seahorse fisheries and trade in both countries were assessed by interviewing participants at many levels of the trade and corroborating those surveys with official trade documents.
• 3. Seahorses were found to be landed primarily as trawl bycatch. Malaysia's catch of 2900 kg year^?1 was less than the estimated domestic consumption (5500–6000 kg year^?1), whereas Thailand's catch of 6600 kg year^?1 apparently far exceeded domestic consumption (～520 kg year^?1).
• 4. Both countries imported seahorses from and exported to other Asian nations. Import statistics from Hong Kong SAR and Taiwan recorded maximum annual trade from Malaysia at 1280 kg year^?1. Trade surveys indicated that Thailand exported at least 5000 kg annually (similar to the estimation of catch), but national Customs records reported 10 500 kg year^?1 in exports, supported by official import records from Hong Kong SAR and Taiwan which indicated that Thailand was the source of up to 11 400 kg year^?1.
• 5. Fishers and traders in both countries reported decreasing availability of seahorses, raising conservation concerns. These apparent declines, in combination with substantial domestic consumption, point towards the challenges that Malaysia and Thailand face in establishing sustainable levels of exports under CITES. Copyright © 2010 John Wiley & Sons, Ltd.

     

转基因动物技术的研究进展

转基因动物是现代生物技术中一个举足轻重的研究领域,目前已有转基因小鼠、猪、牛、鱼、鸡等多种转基因动物问世。文章论述了转基因动物技术的原理、技术方法,以及转基因动物应用的领域,如生产药用蛋白、抗病育种,作为器官移植供体等,同时也指出了转基因动物存在的不足,展望了其发展前景。