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21.
为评估罗非鱼湖病毒(tilapia lake virus,TiLV)跨境传入风险,按照OIE传入风险评估框架,从危害识别、风险评估及风险管理3个方面,开展了TiLV跨境传入风险分析,并提出了相应的风险控制措施。分析认为:活的敏感鱼类(包括亲鱼、鱼卵和鱼苗),用做鲜活饵料的鱼类(野杂鱼)及冰冻和冰鲜的敏感鱼类(包括去除内脏的鱼肉)TiLV传入风险较高,而敏感鱼加工类产品、非敏感鱼类(包括活的和其他形式的产品)及运输活鱼的水、包装、运输工具和用具等传入风险较低。建议不从疫区进口高风险产品,对于低风险产品可以自由贸易,而对运输活鱼的水、包装、运输工具和用具等要进行强制常规消毒。 相似文献
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An experiment was conducted to determine the effects of ad libitum access to feed and water and the option to mix feed and water, all in the same feeder, on the performance of multiparous lactating sows. Feed and water were made available to sows using a self-fed wet/dry (SFWD) or a hand-fed (HF) feed-water system. In the SFWD system, feed and water were dropped into a common trough area of the feeder. The sow determined when and how much of each was dropped. With feed falling onto the flat area of the bottom of the SFWD feeder trough and water falling into the shallow bowl area, and with the 2 areas seamlessly connected, the sow also determined the wetness of the feed consumed. In the HF system, sows were given dry feed twice daily in a J-shaped feeder that was independent of the sow's water source. Sows (n = 114) were assigned to treatments based on parity and genotype. Total feed disappearance per sow during lactation (20 +/- 0.2 d) was greater (P < 0.01) with the SFWD system than with the HF system (120 vs. 110 +/- 4.1 kg, respectively). The SFWD sows had greater (P < 0.01) BW gains during lactation than HF sows (6.2 vs. 0.6 +/- 1.85 kg, respectively). Backfat depth change during lactation did not differ (P = 0.37) between treatments. Likewise, percentage of sows displaying estrus by d 11 post-weaning did not differ (P = 0.51). Piglet weaning BW was greater (P < 0.01) with the SFWD system than with the HF system (6.63 vs. 6.12 +/- 0.22 kg, respectively). Sow average daily water intake and total feed wastage during lactation did not differ (P > 0.66) between treatments. However, sows with the SFWD system wasted less water (P < 0.01) than those with the HF system (15 vs. 232 +/- 12 L, respectively). From a commercial swine production perspective, the difference in waste water volume would result in a significant variation in costs associated with manure storage and distribution. In conclusion, use of a SFWD feed-water system in lactation, which provides sows choices of when to eat, how much to eat, and if dry feed should be mixed with water during consumption, enhances sow appetite, improves litter growth performance, and wastes less water than a HF feed-water system. 相似文献
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随着养鸡生产规模化、集约化的发展,养鸡企业无论在饲养数量和饲养群体上都随之增大.工厂化程度提高,科学养鸡知识的普及,对疾病防疫也有了配套可行免疫程序,大幅降低了因疫病发生死亡的情况,然而,养一只鸡从小到大,意外伤害总是伴随着脆弱的生命.经调查,一般养鸡场因非疾病引起的意外伤亡高达死亡率的50%~60%,甚至造成不可挽回的经济损失,不能不引起高度重视,严加防范. 相似文献
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生物纤维饲料在蛋鸡生产中的应用研究 总被引:1,自引:0,他引:1
生物纤维饲料是对玉米淀粉湿磨国工过程中的浸泡液,黄浆和玉米皮渣等副产品经生物发酵方法而形成的一种新型饲料。本文研究了生物纤维饲料在蛋鸡饲养中的饲喂效果。试验表明,半风干生物纤维饲料(含水分26.68%)以5%比例添加蛋鸡日粮中的饲喂效果与对照组相比,日均产蛋量提高6.4%,平均产蛋率提高6.05%,料蛋比下降13.01%,毛利润提高90.70%,而风干生物纤维饲料(含水分15.44%),则以10%比添加于蛋鸡日粮时,表现出较明显的增产效果,其与对照组相比,日均产蛋量提高4.04%,平均产蛋率提高4.18%,料蛋比下降4.09%,毛利润提高25.74%。 相似文献
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In this present study, the mitochondrial DNA gene cytochrome coxidase subunit I (COI) and the small subunit ribosomal RNA (18S rDNA) gene were used to determine the taxonomic relationships of Psoroptes and Chorioptes mites from China. The neighbor-joining and maximum-parasimony approach were used to evaluate the evolutionary relatedness among different hosts in the genera Psoroptes and Chorioptes. Phylogenetic analysis showed that Psoroptes cuniculi and Psoroptes natalensis may be two different species within the genus Psoroptes, and Chorioptes texanus and Chorioptes panda are different species within the genus Chorioptes. 相似文献