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肉种鸡的体型、体重均大与蛋用型种鸡,它对笼具的要求条件也较高一些。有的场家使用蛋鸡笼饲养肉种鸡或由于肉种鸡笼的造价较高,为节约成本而使鸡笼的规格达不到标准,这将限制肉种鸡遗传潜力的发挥,进而影响它的健康和生产性能。 相似文献
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<正>1选用标准的鸡笼肉种鸡的体型、体重均大于蛋用型种鸡,它对笼具的要求条件也较高一些。有的禽场使用蛋鸡笼饲养肉种鸡,有的为节约成本而使用规格达不到标准的鸡笼,这将限制肉种鸡遗传潜力的发挥,进而影响其健康和生产性能。 相似文献
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分析5250只26周龄的艾维茵48父母代种鸡的产蛋情况并与标准比较,了解产蛋期肉种鸡产蛋性能的变化规律及饲养管理情况。结果表明,随鸡群周龄的增大,累积死淘率逐渐上升,且在产蛋末期明显上升;鸡群产蛋率在26-30周龄低于标准,在产蛋末期产蛋率下降幅度增加;鸡群的合格蛋率相对较高;合格蛋受精率在26-34周龄上升缓慢且低于标准受精率,此后呈波动性缓慢下降,且始终低于标准受精率。在种鸡生产中,加强饲养管理可以提高种鸡产蛋性能。 相似文献
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肉种鸡产蛋高峰后的减料李增全(山东省潍坊中粮华潍食品有限公司第三种鸡场262100)肉种鸡产蛋高峰后的减料是目前种鸡生产过程中技术含量较高的一环,是关系到种鸡一生生产水平的极重要的技术措施。生产者都清楚种鸡全程减料量为高峰科量的15%,但是如何将这1... 相似文献
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由于笼养在提高受精率、节省饲料、方便限饲和增加单位面积饲养量等方面具有明显优势,近年来,越来越多的肉种鸡场采用了笼养方式饲养种鸡。但是,由于肉种鸡体格比普通蛋鸡大,产蛋位置高,蛋下落的撞击力自然要比普通蛋鸡大。而肉种鸡的饲养笼具又大多是参照蛋鸡笼设计的,其底网构造不甚合理, 相似文献
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能量是关键白营养因素 肉种鸡的体型相对较大,因此尽管产蛋量相对较低,但能量需要量仍然比商品蛋鸡高得多。肉种鸡在高温条件下的能量需要量较高,所以在炎热气候条件下,肉种鸡产蛋高峰期间的饲喂将面临挑战。 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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以国际标准强毒R株人工感染非免疫产蛋鸡,定时扑杀,分别从鼻窦、眶下孔、气管、肺、气囊、卵巢和输卵管分离MG,并收集感染鸡所产蛋分离MG。结果表明,人工感染48小时后上、下呼吸道及肺已被全面感染,96小时气囊已被感染,120小时输卵管已能分离到MG,卵巢始终分离不到MG。人工感染鸡自144小时便能在其所产蛋中分离出MG。药物治疗能在72小时内消除感染,油乳剂苗则需24天后逐渐降低蛋内MG分离率,药物卵内注射、种蛋药浴、高温处理均能杀死卵内MG,但以研制的种蛋浸泡剂药浴效果为最好。 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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