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采用杂交、回交、成对品种系统选育等方法育成了九(921)、华(923)、春(922)、早(924)4个新品种,经配合力测定组配成四元杂交种九.华×春.早.实验室鉴定、农村试养、蚕种场繁育结果表明该品种强健好养,制种性能好,茧形大而匀整,茧丝品质良好,综合经济性状优良. 相似文献
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以胚胎移植法测定高温对胚胎发生有害作用的时间以及子宫内膜机能在造成死亡中所起的作用。试验时共用黑脸母羊100只,先在草地放牧,1958年在配种前期内将发情时间差别不超过24小时的母羊进行胚胎移植,即由供体的轨卵管中取出胚胎,移植到受体的子宫中。在发情后几天将母羊按发传时间配对,由草地移至70℉或90℉的定温室中,相对湿度皆为65％。1958年配种后期及整个1959年配种期内用激素控制卵巢活动,使母羊在移植前发 相似文献
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正据《北方园艺》2018年第8期《拉枝角度对普通型和短枝型"富士"苹果树体生长生理特性和果实品质的影响》(作者李长亮等)报道,为了探究拉枝角度对普通型和短枝型"富士"苹果树体生长生理特性和果实品质的影响,在田间条件下不同拉枝角度对普通型和短枝型富士苹果树体生长特性和果实品质的影响进行对比研究。 相似文献
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1. Uneviscerated and eviscerated chicken carcasses were processed together and stored in groups of 10 at 10°C and 4°C; a further 10 eviscerated carcasses were wrapped in “polythene” bags and stored at 4°C.
2. The bacteriological condition of the uneviscerated and eviscerated carcasses prior to storage was very similar.
3. At 10 °C the eviscerated carcasses developed a slight “off” odour in 3 to 4 d (average 3.5 d) whilst the first signs of greening in the uneviscerated carcasses occurred in 4 to 6 d (average 5 d).
4. At 4 °C wrapped eviscerated carcasses developed slight “off” odour in 5 to 6 d (average 5.6 d) whilst the unwrapped eviscerated carcasses varied considerably in their shelf‐life from 5 to 11 d (average 7.9 d). After 18 d the uneviscerated carcasses were still quite acceptable and no bacteria were found in the breast muscle (i.e. < 150/g).
5. Bacteriological examinations made of the skin of the three groups of chickens stored at 4 °C confirmed the differences obtained in shelf‐life; Pseudomonas spp. were found to be the predominant spoilage organisms in each case. 相似文献
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<正> 羊骨盆狭窄性难产在兽医临床上较多见。治疗办法历来是:1.借助器械将胎儿强行拉出;2.剖腹产;3.截胎术。但这三种方法都势必伤及胎儿或母畜。我们试用倒转胎儿180°的方法治疗28例均获成功。症状为胎水巳排出,胎儿仅露出二前肢一部分(或无任何外 相似文献
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番鸭种蛋由于其个体大，在老式孵化机中定时90°角翻蛋难以满足胚胎正常发育的要求，从而影响了孵化率。我场对孵化中的第2～21d番鸭胚蛋采用每日一次手工180°翻蛋（以下简称手工翻蛋），受精蛋平均孵化率由原来的85％提高到90％以上，效果极为显著。但由于手工翻蛋费工费时，且番鸭种蛋孵化期长，究竟在孵化期间的哪一阶段实施手工翻蛋既能缩短翻蛋时间又能获得高的孵化率，特进行本试验。1试验材料和方法1．1 种蛋来源黑白花番鸭种蛋，全部来自本场种鸭群。1．2 贮蛋架其作用是供试验组的种蛋盘经手工翻蛋后，以及对照组的种蛋盘（未经… 相似文献
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Ander Arando Juan Vicente Delgado Alejandra Bermúdez-Oria José Manuel León África Fernández-Prior Sergio Nogales Carlos C. Pérez-Marín 《Reproduction in domestic animals》2020,55(3):325-332
The aim of the present study was to evaluate the effect of the addition of two olive oil-derived antioxidants, hydroxytyrosol (3,4-dihydroxyphenylethanol, HT) and 3,4-dihydroxyphenylglycol (DHPG), on ovine semen during liquid storage at 5°C and 15°C. Semen was collected, pooled, diluted and then divided into aliquots supplemented with different concentrations (5 μg/ml, 10 μg/ml, 50 μg/ml and 100 μg/ml) of HT, DHPG and a mixture (MIX) of both antioxidants. Sperm motility characteristics were assessed in the different samples at 0, 6, 24, 48, 72 and 96 hr after cooling, and a fertility trial was also conducted. The results showed that the antioxidant addition did not significantly improve total and progressive motility in ovine cooled sperm maintained at 15° or 5°C. However, in samples stored at 5°C, LIN (48, 72, 96 hr), STR (0 hr) and WOB (0, 48, 72, 96 hr) values significantly decreased in comparison with control treatment when high antioxidant concentrations were added (MIX100 or HT100). When samples were maintained at 15°C, MIX50 showed significantly higher VCL values than the control treatment after 6 hr cooling, and MIX100 showed significantly lower VCL values at 96 hr after cooling. According to the artificial insemination trial, no significant differences were observed when antioxidants were added. In conclusion, the use of HT and DHPG showed small impact in sperm motility and fertility was not affected (nor detrimentally nor positively) when insemination was carried out using antioxidant-supplemented liquid sperm. 相似文献
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Nerys M. Griffiths 《British poultry science》1975,16(1):83-87
1. Pheasants hung at 10 °G were found to become increasingly “gamey” in flavour and more tender in texture with length of hanging.
2. After 13 d they were strongly gamey and very tender. 相似文献
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《中国畜牧杂志》2015,(Z1)
畜牧业生产中仅仅获得高生产力是不够的。现代社会对于较高的动物生产力、动物产品质量与安全、动物福利与健康、环境保护和生物多样性的要求越来越高。人们在动物福利、环境、产品安全和质量方面日益提高的意识和重视,使它们成为涉及到动物的食品生产体系中的优先考虑因素。畜牧业正在向更为可持续的路线转变,必须考虑多种复杂变化情况下(包含经济、生态和社会等各个方面)的可持续性问题,并认识到农业产业具有衔接人类与自然系统的特殊功能。局部解决方案已经不能产生预期结果。例如,任何保持现状的努力,如果忽略经济发展、食品安全和生计需要都不可能成功。相反地,如果生态系统和社会系统不具备适应短期和长期变化的能力,社会经济的发展也不会持续。这个复杂的问题需要将可持续性作为一个社会问题来考虑;需要大范围利益相关者的整体努力来利用畜牧生产体系的力量,减少动物产品需求和供给的快速发展所带来的潜在负面影响。这些努力应该是现实的、公平的,并考虑到生态、社会经济和文化层次的,这一点非常重要。本文将呈现如何以360°视角观察动物营养学及其未来研究与发展的框架。正像目前所有部门和畜牧产业服务部门一样,动物营养学也正面临一个转折点。动物营养学直接影响动物的生产力、动物产品安全与质量、动物福利和健康、环境保护和生物多样性。此外,动物营养还影响食品和能源竞争、土地利用和土地流转、全球氮循环。动物营养学家遵循可持续动物日粮原则以及利用基于360°视角的未来研究与发展的框架作为指导工具,成为使畜牧业转向可持续发展方向的领航者。为降低畜牧业可持续发展过程中的不利影响,动物营养学家需要与环境、经济、社会科学和公共健康等领域专家合作,制订出一个多方论证的方法。所提出的框架可以发掘这些专家的专业技能和专业知识,从而使得畜牧业可持续发展。合适政策和制度的支持同等重要。因此,科学家也需要与政策制订者、私营部门、民间团体和农场主合作,来帮助找到利于环境、社会和经济可持续发展的方法。同样,多角度思考动物生产最大化到最佳化的思维模式转变也非常必要。 相似文献
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1. The aim of this study was to investigate the stability of immunoglobulin-Y (IgY) in stored eggs from immunised hens. 2. Eggs from individual hens were randomised and stored for up to one month at room temperature, or for up to 6 months at +4°C. IgY was extracted from the egg yolks and the antibody activities were tested by ELISA. 3. There was no significant reduction in antibody titres with egg storage under these conditions. 4. Egg yolks of immunised chickens provide an inexpensive source of large amounts of polyclonal antibodies for use in immunotherapy and immunoassays. By collecting eggs from different immunised hens and pooling their yolks, it should be possible to reduce batch-to-batch variation. 相似文献