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近年来,食品安全引起人们的广泛关注,禽病的有效防治切实关系到人们的餐桌安全,因此要提高对禽疫病预防控制的重视度,有针对性的做好免疫工作.中药多糖有着独特的理论体系,将其作为免疫增强剂应用于家禽养殖业已成为热点.为了提高家禽疫苗免疫效果,增强机体免疫力,笔者参阅并综合分析大量黄芪多糖(APS)用于家禽疫苗的相关文献,总结... 相似文献
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家禽免疫增强剂及其应用 总被引：4，自引：0，他引：4
家禽免疫增强剂及其应用陈峰毕英佐曹永长何洁（华南农业大学家禽研究室５１０６４２）为了提高家禽机体的免疫应答，对家禽免疫增强剂进行研制已成为一个十分活跃的领域，引起了人们的极大关注。但目前各种家禽免疫增强剂的研制大部分处于早期阶段，人们对其尚未完全认识... 相似文献
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据有关部门调查，目前我国禽病已达80余种．其中许多疾病具有免疫抑制性．鸡群一旦感染，往往造成免疫系统如胸腺、法氏囊、骨髓和脾脏的萎缩及相关功能紊乱，严重损害了机体的免疫功能．增加了细菌性疾病、霉形体、寄生虫病的易感性，造成了复杂的混合感染．大幅增加了家禽的发病率和治疗难度．因此研究和开发有效的免疫增强剂，保证和维持鸡体免疫系统的完整和正常功能．可有效防制禽类传染病的发生．提高机体对其他疫苗的免疫接种发生更为有效的反应。 相似文献
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近年来随着我国养猪业的迅速发展,集约化程度的提高,国内外畜禽贸易的Et益频繁,疾病传播机会增加,传染病频繁流行,多种类型病原混合感染,免疫抑制性疾病危害加大,造成疫苗免疫效果不佳,严重影响了养猪业的发展。免疫增强剂具有提高机体免疫系统功能,增强机体抗病力,减少疾病发生等特点,近年来对免疫增强剂的研究逐渐引起了普遍关注和重视,研制出了多种免疫增强剂应用于养猪生产,但是化学药物免疫增强剂存在毒副作用和药物残留弊端,中草药免疫增强剂对机体具有双向调节作用,无毒副作用和药物残留,因此成为近年来十分活跃的研究领域。 相似文献
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近年来,我国规模化养猪业迅速发展,疾病传播机会增加,免疫抑制性疾病危害加大,不良应激因素增多,疫苗免疫效果不佳,传染病频繁发生流行,给养猪业造成严重损失。免疫增强剂具有提高机体免疫系统功能,增强机体抗病力,减少疾病发生等特点,因此对免疫增强剂的研究和应用逐渐引起了养猪界的普遍关注和重视,各种免疫增强剂提高机体免疫水平的报道日趋增多,成为近年来十分活跃的研究领域。 相似文献
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１合理安排注射时间产蛋家禽的预防注射，一般在开产前或停产后进行最宜。这是因为家禽进入产蛋期后，机体的生理变化是有规律的，故养殖场或养殖户要合理安排家禽的饲养管理，以适应产蛋家禽的生理变化。如家禽在产蛋期防疫注射，一方面会因注射疫苗和菌苗致机体的生理规律发生紊乱，导致产蛋量减少或患呼吸道疾病，另一方面会因预防注射，使之产生应激综合症，引起产蛋量下降。２注意观察禽群健状况在注射疫苗前，要注意观察禽群的健康状况，只有健康的家禽才可以接种疫苗。明显的病弱禽不能接种。病弱残禽免疫应答差，不易产生满意的免疫… 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