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为了查找种公牛精液品质下降的原因并探讨精液品质与微量元素的关系,试验测定了种公牛基础日粮及血液、被毛、精液中锌(Zn)、铜(Cu)、铁(Fe)、锰(Mn)、铬(Cr)5种微量元素含量。结果表明:饲料中Zn、Cu含量明显低于美国NRC推荐标准,Fe、Mn、Cr三种元素能满足种公牛的营养需要;精液品质正常牛及异常牛血液、被毛、精液中Fe、Mn、Cr差异不显著(P>0.05),被毛、血液中Zn、Cu两种元素含量差异显著(P<0.05),精液中Zn元素含量差异极显著(P<0.01)、Cu元素含量差异显著(P<0.05)。 相似文献
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精液产量与质量是衡量种公畜品质优劣最重要的指标,也是影响其遗传潜能发挥的重要因素,因此提高种公畜精液品质意义重大。研究发现,日粮中添加钙、锌、铁、硒、铜等微量元素能够影响种公畜精液品质。本文针对影响种公畜精液品质的微量元素锌、硒、铜相关研究进展作一综述,为找出微量元素与精液品质之间的关系提供理论参考依据。 相似文献
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锌对黑白花种公牛精液品质及某些生化指标的影响 总被引:8,自引:0,他引:8
锌对黑白花种公牛精液品质及某些生化指标的影响莱阳农学院动科系李文立任慧英南京农业大学陆治年锌作为种公牛营养中一种重要的必需微量元素参与机体内几乎所有的物质代谢过程,对种公牛的繁殖性能影响很大。早在1921年,人们就发现锌和雄性动物的生殖机能有关。近年... 相似文献
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种公猪精液品质与微量元素关系研究 总被引:4,自引:0,他引:4
对14头种公猪精液品质下降原因进行了7种微量元素的检测分析,结果表明,检测组精液中Zn,Se、Co三种元素含量分别比对照组少40.4%,51.2%和31.6%,两组比较差异达极显著水平和显著水平。A组鬃毛中Zn、Se、Co三种微量元素含量分别比B组少43.3%、48.6%和26%。其他4种微量元素含量差异不显著。结果还表明,种公猪精液品质下降与Zn、Se、Co三种微量元素含量偏低有直接关系。 相似文献
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试验旨在通过对新疆地区安格斯、和牛、利木赞、夏洛来和西门塔尔5个品种种公牛全年精液品质分析,探究不同季节与品种对种公牛精液品质的影响,为冻精生产提供理论依据。选择3~5岁的5个品种的种公牛106头,收集其2018—2019年采精量、原精活力和原精密度共2 211条数据,使用SAS 9.2软件进行分析。结果表明:季节及品种对种公牛精液品质均有极显著影响,其中夏洛来种公牛采精量高于和牛、利木赞及西门塔尔(P<0.01),利木赞种公牛的原精活力高于安格斯、夏洛来(P<0.01),和牛的原精密度高于安格斯和夏洛来(P<0.01);春季的采精量、原精活力及原精密度均高于其他季节(P<0.05或P<0.01)。综上,就新疆地区种公牛精液品质而言,利木赞、夏洛来和西门塔尔种公牛的精液品质相对好于其他品种;春、秋两季种公牛的精液品质较好,建议将精液采集的工作集中在春、秋两季。 相似文献
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于广忠 《养殖与饲料.饲料世界》2022,(1)
在人工授精技术发达的当今时代,种公牛精液品质的优劣可直接决定奶牛生产性能和养殖场经济效益的好坏,尤其在规模化养牛场更是如此。为此,本文从种公牛的品种、年龄、营养、季节、温度、湿度、光照、环境噪音、疾病、药物和精液采集等方面对影响种公牛精液品质的因素进行了分析和总结,以期为种公牛精液品质的管理和提升提供理论依据。 相似文献
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种公牛选种及饲养管理的要点 总被引:1,自引:0,他引:1
种公牛营养水平的高低直接影响着生产能力的发挥。营养是种公牛维持生命和提高生产力的物质基础,能量、蛋白质、矿物质、微量元素、维生素等失衡和不足都会影响精液品质与产量,冬天过冷、夏天 相似文献
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魏静 《四川畜牧兽医学院学报》2009,(4):28-32
在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。 相似文献
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本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。 相似文献
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REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air. 相似文献
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Effects of size of ingestively masticated fragments of plant tissues on kinetics of digestion of NDF
Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo. 相似文献
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乳酸杆菌作为益生菌广泛用于人和动物.本文综述了乳酸杆菌改善宿主健康的机制.乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道.文章重点讨论了乳酸杆菌表面成分(表面蛋白、脂磷壁酸和肽聚糖)与肠道受体(C型凝集素受体、Toll样受体和Nod样受体),阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制. 相似文献