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前言 应用杂交手段以取得生物的杂交效益始终是提高养猪效益的重要方法,但是简单的杂交不一定会取得最佳的杂交效益。为了取得最佳的杂交效益,养猪工作者们在上世纪60年代开始,根据玉米杂交及鸡杂交配套系培育方法的启发下,开始了猪配套系培育的工作。由于配套系培育是既对专门化品系的系内选择,又 相似文献
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我国家兔配套系的培育和推广大致经历对引入配套系进行保种和扩繁、开展配套系育种研究和国内配套系开始走向市场3个阶段。目前存在的主要问题是育种上表现急于求成、推广中随意改变配套模式、不重视配套系的饲养管理以及对配套系宣传和推广不够等。作者在分析我国家兔配套系培育与推广现状和存在问题的基础上,提出我国家兔配套系育种中应注意的问题及发展走向。 相似文献
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猪配套系选育几个技术问题的探讨 总被引：2，自引：0，他引：2
由于配套系育种工作在我国还处在初始阶段,囚此如何培育配套系众说不一。本文根据深农猪配套系培育的经验和教训,对猪配套系培育的技术进行探讨,以抛砖引玉并作为接受批评之靶的,共同找出培育具有我国猪特色的配套系的最佳方法。 1 猪的配套系培育工作含有高的技术内涵,与作物杂交及鸡的配套系有很大的不同 相似文献
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龙宝1号猪品种(配套系)培育概述 总被引：1，自引：1，他引：0
<正>1来源龙宝1号猪配套系是广西扬翔股份有限公司与中山大学等单位经过13年时间培育完成的。通过陆川猪、隆林猪、大白、长白、杜洛克等品种间的6种不同杂交组合试验,确定大长陆三元杂交为最优配套组合。在专门化品系培育过程中,运用现代猪育种原理与方法,以广西名优地方猪种陆川猪为育种素材培育了母系母本(LB33),重点对繁殖性能、肉品质和适应性进行选育;利用公司庞大的瘦肉型猪育种体系,以长白猪 相似文献
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《畜牧兽医科技信息》2009,(9):15-15
2009年4月18日,我国成功自主培育的"京红1号""京粉1号"蛋鸡配套系在北京举行揭牌仪式.曾以育出"农大三号"蛋鸡而蜚声中外的中科院院士、中国农业大学教授吴常信评价说,"京红1号"和"京粉1号"蛋鸡配套系的成功培育,打破了长期以来祖代蛋鸡品种受制于人、完全依赖国外进口的格局. 相似文献
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猪配套系育种及 湘沙猪配套系选育工作体会 总被引：1，自引：0，他引：1
本文阐述了有关猪配套系育种的概念、 关键技术环节、 育种目标的科学制定及专门化品系选育的主要方法;介绍了湘沙猪配套系选育背景、 主要育种技术措施及选育工作进展;提出了培育含地方猪种血统的优质猪配套系,有利于建立我国地方猪种繁育利用体系、 有利于促进地方猪种市场开发、 有利于地方猪种资源的科学保护、 有利于利用国外种猪的高性能加快育种进程、 有利于提升地方猪种的种质研究水平. 相似文献
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5 猪配套系的培育 经国家畜禽品种审定委员会审定的猪配套系有8个(见表10).除上述国家审定的猪配套系外,尚有省级告禽品种审定委员会审定的猪配套系,如由甘肃农大等5单位联合培育的华特猪配套系(1999年5月通过省级审定);由湖南农大与正虹原种猪场共同培育的湘虹猪配套系以及与益阳市农科所共同培育的湘益猪配套系(2006年6月通过省级审定). 相似文献
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Meschan EM Peham C Schobesberger H Licka TF 《Veterinary journal (London, England : 1997)》2007,173(3):578-584
As there is no statistical evidence that saddle fit influences the load exerted on a horse's back, this study was performed to assess the hypothesis that the width of the tree significantly alters the pressure distribution on the back beneath the saddle. Nineteen sound horses were ridden at walk and trot on a treadmill with three saddles differing only in tree width. Kinetic data were recorded by a sensor mat. A minimum of 14 motion cycles were used in each trial. The saddles were classified into four groups depending on fit. For each horse, the saddle with the lowest overall force (LOF) was determined. Saddles were classified as "too-narrow" if they were one size (2 cm) narrower than the LOF saddle, and "too-wide" if they were one size (2 cm) wider than the LOF saddle. Saddles two sizes wider than LOF saddles were classified as "very-wide". In the group of narrow saddles, the pressure in the caudal third (walk 0.63 N/cm(2)+/-0.10; trot 1.08 N/cm(2)+/-0.26) was significantly higher compared to the LOF saddles (walk 0.50 N/cm(2)+/-0.09; trot 0.86 N/cm(2)+/-0.28). In the middle transversal third, the pressure of the wide saddles (walk 0.73 N/cm(2)+/-0.06; trot 1.52 N/cm(2)+/-0.19) and very-wide saddles (walk 0.77 N/cm(2)+/-0.06; trot 1.57 N/cm(2)+/-0.19) was significantly higher compared to LOF saddles (walk 0.65 N/cm(2)+/-0.10/ 0.63 N/cm(2)+/-0.11; trot 1.33 N/cm(2)+/-0.22/1.27 N/cm(2)+/-0.20). This study demonstrates that the load under poorly fitting saddles is distributed over a smaller area than under properly fitting saddles, leading to potentially harmful pressures peaks. 相似文献
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M. Masko M. Domino K. Skierbiszewska Ł. Zdrojkowski T. Jasinski Z. Gajewski 《Equine Veterinary Education》2020,32(12):654-663
Complications in late gestation are challenging problems for the equine clinician and are causes of considerable distress to owners. Health problems in a pregnant mare in each stage of gestation can adversely affect the pregnancy. It is important to obtain a thorough history and perform a detailed and systematic examination of the pregnant mare so that the mare may be classified as normal or high-risk. However, even after a thorough examination, practitioners may face problems with the interpretation and assessment of risk. Normal mares should foal in the stable or pasture. Mares classified as having a high-risk pregnancy need to be monitored precisely for signs of oncoming foaling with attendance of trained personnel when labour begins. A valuable method for monitoring of the high-risk mare is assessing fetoplacental well-being. Fetoplacental well-being is most accurately assessed with ultrasonography as well as several available hormone profiles. We are proposing our scoring system of the mare's health, which may be useful in the assessment of risk during pregnancy and help clinicians to decide whether sending the mare to the clinic is reasonable or unnecessary. 相似文献
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Webbon P 《Equine veterinary journal》2012,44(1):8-12
The understanding and application of genetics have grown extremely quickly since it has become possible to sequence the whole genome of an organism. The human genome sequence was completed in 2001 and that of the horse in 2007. The significance of this is that it makes it more feasible to explain how both genetically simple and complex traits are transmitted from one generation to the next and, therefore, to make informed breeding decisions, modify how horses are managed and trained to minimise the risk of disease and injury, and improve methods of prevention, diagnosis and treatment of many conditions. The science of genetics/genomics will continue to grow internationally, limited only by the funds available. The application of the science to man, horses and other species raises very complex moral and commercial issues. Thoroughbred breeders are perceived by some as resistant to change, but their apparent intransigence is often based on a genuine concern for the integrity of the breed. By taking control of the application of the advances in genetics, the Thoroughbred industry potentially has the opportunity to improve both the health and performance of Thoroughbreds. If, however, the science is applied in an uncoordinated manner, driven by commercial interests with no underlying concern for the horses themselves, there is a very real risk that breeders, the Thoroughbred breed and individual horses will all suffer as a consequence. 相似文献
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为了找出支配鸡胆囊交感节后神经元的分布规律,选用体重1.5 kg～2.5 kg的成年母鸡6只,将CT-HRP溶液注入胆囊壁,动物存活3 d～4 d后,经左心室灌流固定,取内脏神经节、肾上腺神经节以及双侧胸、腰和荐段交感干神经节,制成50 μm的连续冰冻切片,TMB法呈色反应,置明视野显微镜下观片统计.结果发现,支配鸡胆囊的交感传出神经元胞体位于内脏神经节(占41.1%)、肾上腺神经节(占40.5%)和T2～T7交感干神经节(占18.4%),在交感干神经节中标记细胞的峰值位于T5、T6交感干神经节.所有的标记细胞以位于右侧的占优势. 相似文献
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犊牛腹泻与肠道菌群的变化 总被引：1，自引：0，他引：1
本文检测腹泻犊牛的直肠内8种主要正常菌群的变化,并与健康犊牛进行对比。结果发现,犊牛腹泻时,大肠杆菌、双岐杆菌和乳杆菌变化较大,而其它菌群变化较小。腹泻或将腹泻时,大肠杆菌数增加,双岐杆菌和乳杆菌数下降。腹泻康复或即将康复时,大肠杆菌减少,双岐杆菌、乳杆菌数增加。 相似文献
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试验选择陕北白绒山羊繁育中心羊场的成年健康母羊（怀孕前期）16只,育成母羊13只,育成公羊13只,空腹称重。测定每只羊1d的采食量,计算其摄入的营养成分含量,并与原苏联绒用山羊饲养标准比较,进行饲养水平评价。结果显示,与饲养标准比较,陕北白绒山羊繁育中心羊场的育成母羊代谢能高2．68MJ,粗蛋白低59．29g,钙低3．00g,磷低1．52g;育成公羊代谢能高3．47MJ,粗蛋白低81．92g,钙低4．42g,磷低2．62g;成年母羊代谢能高2．51MJ,粗蛋白低91．33g,钙低3．09g,磷低1．93g。结合羊的体况综合评价饲养水平基本合理,但尚需要按饲养标准增加粗蛋白、钙、磷等营养物质的供给量。 相似文献