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蛋鸡产蛋率达８０％－９０％时即进入产蛋高峰期，一般产蛋高峰期可维持４个月左右。若品种优良，饲养科学，可延长蛋鸡的产蛋高峰期，直接提高蛋鸡全年的总产蛋水平。那么，影响蛋鸡产蛋高峰期的因素有哪些呢？１蛋白质水平产蛋高峰期间蛋鸡对蛋白质需要量随产蛋率的上升而增加。可见，饲料中蛋白质的含量，对蛋鸡产蛋率的高低有着直接的影响。因此，应在蛋鸡产蛋率达９０％时，就提前喂给蛋白质含量达１９％的日粮，促使产蛋高峰迅速到来。为延长产蛋高峰期，当产蛋率下降时，日粮中蛋白质水平要推迟一周再降低，以使产蛋率下降的速度慢一… 相似文献
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《畜牧兽医科技信息》2020,(6)
通过在基础日粮中添加油脂研究其对蛋鸡产蛋性能的影响,为评估油脂在蛋鸡产蛋高峰后期对生产性能的影响提供依据。试验选用8200只520日龄京红蛋鸡,分成对照组(520～540日龄)和试验组(541～560日龄),对照组不添加油脂,试验组在日粮配比相同的情况下添加1%某品牌大豆油。结果显示:添加油脂试验组蛋鸡产蛋率与对照组产蛋性能差异不显著(P0.05),说明油脂在蛋鸡产蛋高峰后期对生产性能影响不大。 相似文献
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试验旨在研究在产蛋高峰后期蛋鸡日粮中添加酿酒葡萄皮渣(wine grape pomace,WGP)对蛋鸡生产性能、蛋品质及血液抗氧化水平的影响。选用61周龄体重、产蛋率相近的京红蛋鸡300只,随机分为5组,每组4个重复,每个重复15只。对照组饲喂基础日粮,WGP1组、WGP2组、WGP3组、WGP4组分别饲喂基础日粮+3%酿酒葡萄皮渣、基础日粮+5%酿酒葡萄皮渣、基础日粮+7%酿酒葡萄皮渣、基础日粮+9%酿酒葡萄皮渣,预试期3 d,正式期30 d。结果表明:添加WGP对产蛋高峰后期蛋鸡产蛋率、平均蛋重、蛋料比、破损率影响差异不显著(P0.05);日粮中添加WGP对产蛋高峰后期鸡蛋蛋白高度、蛋形指数影响差异不显著(P0.05);哈夫单位WGP1、WGP2、WGP4组有增加趋势,但试验第1周期均显著低于对照组(P0.05);在蛋鸡日粮中添加WGP可以减缓蛋黄颜色的降低;WGP4组在第2周期内蛋壳强度较对照组差异性显著(P0.05)。在产蛋高峰后期蛋鸡日粮中加入酿酒葡萄皮渣可以显著提高血液抗氧化能力,3%~7%的添加可降低血液胆固醇,但高水平添加会使得血液胆固醇含量增高。 相似文献
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1分阶段饲养不可忽视 把商品蛋鸡的产蛋期分为3段，各阶段喂给不同营养水平的日粮，以满足其产蛋需要。产蛋前期，即从开产到产蛋高峰，产蛋率大于80％以上，这一时期日粮中蛋白质、钙等营养含量应随鸡群产蛋率的增长而增加：产蛋中期，即产蛋高峰过后的一段时期，产蛋率在65％～80％；产蛋后期，产蛋率小于65％。后两阶段日粮中蛋白质、钙、磷等含量随鸡群产蛋率的下降而减少。 相似文献
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蛋鸡生产应注意几个问题 总被引：1，自引：0，他引：1
一 分阶段饲养不可忽视
把商品蛋鸡的产蛋期分为三段，各阶段喂给不同营养水平的日粮，以满足其产蛋需要。产蛋前期，即从开产到产蛋高峰，产蛋率大于80％以上，这一时期日粮中蛋白质、钙等营养含量应随鸡群产蛋率的增长而增加；产蛋中期，即产蛋高峰过后的一段时期，产蛋率在65％～80％产蛋后期，产蛋率小于65％。后两阶段日粮中蛋白质、钙、磷等含量随鸡群产蛋率的下降而减少。 相似文献
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为研究桑枝叶提取物对蛋鸡产蛋高峰后期生产性能和蛋品质的影响,试验选择47周龄体重相近、健康、采食正常的罗曼粉蛋鸡324只,随机分成4组,每组3个重复,每个重复27只鸡。对照组(试验Ⅰ组)饲喂基础日粮,试验组Ⅱ、Ⅲ、Ⅳ分别在基础日粮中添加0.2%、0.4%、0.8%的桑枝叶提取物,预试期7d,试验期64d。结果表明:(1)与对照组相比,日粮中添加0.2%、0.4%和0.8%的桑枝叶提取物均可显著降低蛋鸡产蛋高峰后期的次蛋率(P<0.05),降低比例分别为27.08%、54.87%和58.48%,显著提高蛋壳厚度(P<0.05);(2)与对照组相比,日粮中添加0.4%和0.8%桑枝叶提取物可显著提高蛋鸡产蛋高峰后期的产蛋率、日采食量和蛋黄颜色(P<0.05),其中蛋黄颜色指数分别增加12.95%和15.81%,同时可显著降低料蛋比(P<0.05),较对照组分别降低3.31%和4.55%;(3)随着桑枝叶提取物添加量的提高鸡蛋哈氏单位和蛋黄重均有逐渐增加的趋势,但与对照组相比差异不显著(P>0.05)。综上所述,日粮中添加0.4%和0.8%的桑枝叶提取物可提高蛋鸡产蛋高峰后期的总体生产性能,并对鸡蛋品质有一定的改善作用。 相似文献
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(一)分阶段饲养不可忽视 把商品蛋鸡的产蛋期分为三段,各阶段喂给不同营养水平的日粮,以满足其产蛋需要。产蛋前期,即从开产到产蛋高峰,产蛋率大于80％以上,这一时期日粮中蛋白质、钙等营养含量应随鸡群产蛋率的增长而增加;产蛋中期,即产蛋高峰过后的一段时期,产蛋率在65％ 相似文献
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在１４４０只星杂５７９蛋鸡日粮中添加３％、５％、８％、１ｌ％的ＧＳＤ－高效水解蛋白饲料替代进口鱼粉和豆粕，进行１０３无的饲养试验。结果表明，日粮添加５％ＧＳＤ－高效水解蛋白饲料和合成氨基酸时，产蛋性能比添加３％ＧＳＤ－高效水解蛋白饲料高，饲料成本亦最低。蛋鸡日粮中添加ＧＳＤ－高效水解蛋白饲料对产蛋高峰有影响，但５％的添加量不影响产蛋鸡的健康。 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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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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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