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鸡球虫病免疫:Ⅰ.球虫病特点和免疫原理 总被引:2,自引:0,他引:2
采用免疫方法控制球虫病已经成为一种趋势,因为它可以从根本上免除球虫抗药性和肉蛋品药残带来的一系列问题。但是随着进入市场球虫病疫苗种类的增多也带来不少问题。球虫病疫苗有毒苗和弱毒苗之分.有三价、四价、五价、七价甚至八价之分。有商品肉鸡用的,也有种鸡用的。商家宣传也各有动人之处,令人眼花缭乱.不知何以适从?如果你了解了球虫和球虫病的重要特点,了解了球虫免疫的原理就能够释疑解惑,就能够理性地选择和正确使用球虫病疫苗。本文拟就上述几个方面介绍,以飧读者。 相似文献
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鸡球虫病是一种危害严重的寄生虫病。鸡球虫病疫苗是近几年开发出的一类逐渐被用户所认识并接受的新产品。它的使用,解决了生产实际中药残高、球虫易产生耐药性等许多难题。由于球虫病疫苗既符合现代绿色食品的需要,又可解决药残高、球虫易产生耐药性等问题,因此具有广阔的应用前景。但多数用户对该类产品的特性和用法不很了解,疫苗的保存或使用因操作不当而造成免疫失败时有发生,因此,正确认识影响鸡球虫病疫苗免疫效果的因素非常重要。 相似文献
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鸡球虫病一直困扰着养殖业,是一种严重危害养鸡业发展的寄生虫病。几乎所有鸡场都存在本病。近年来,理想的球虫疫苗免疫带来了新的希望。本文就球虫病疫苗免疫的若干事宜进行探讨。 相似文献
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球虫免疫和疫苗研究的进展山于集约饲养家禽,球虫病仍然是一个全球性,对养禽业具有经济意义的重要疾病.球虫病通常是靠化学药物控制的,因而增加了发生球虫的抗药虫株,急需发展替换的战略.发展有效的球虫班苗是可能的,因为这种寄生虫的自然感染是自我控制的,并且最... 相似文献
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强效艾美耳牌鸡球虫疫苗免疫效果的研究 总被引:17,自引:3,他引:17
本实验研究了强效艾美耳牌鸡球虫疫苗免疫预防鸡球虫病的效果。实验结果表明:强效艾美耳牌鸡球虫疫苗是安全有效的,基保滴服免疫的效果优于拌料免疫,滴服免疫不仅对攻毒后鸡有100%的保护效果,而且能有效地控制球虫病的发生,对小鸡的生长也有明显的保护作用。与常用抗球虫药氯苯胍相比,强效艾美耳牌鸡球虫疫苗预防鸡球虫病的效果优于氯苯胍,其对小鸡增重率、料肉比显示的效果也优于氯苯胍。 相似文献
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鸡球虫DNA疫苗研究进展 总被引:1,自引:0,他引:1
鸡球虫病是严重危害养禽业的一种寄生虫病。一直以来,鸡球虫病主要依靠药物来进行防制。但是,随着球虫抗药性问题的日益严重、抗球虫新药开发困难及人们对食品安全的关注,药物在球虫病控制中的作用越来越受到限制,因而人们期望用更好的手段来控制鸡球虫病。DNA疫苗是近年发展起来的一种新型疫苗,因其安全、稳定、高效和易于制备而得到广泛研究。随着鸡球虫保护性抗原基因的不断发现,以及对细胞因子等免疫佐剂在抗球虫感染中的作用不断深入探索,鸡球虫DNA疫苗的研究引起人们的广泛关注和极大兴趣。本文就鸡球虫DNA疫苗作用机理、抗原基因、载体、免疫佐剂、免疫途径、免疫剂量、免疫程序及DNA疫苗研究进展方面展开一系列论述。 相似文献
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鸡球虫微囊型疫苗的研制及免疫效果 总被引:1,自引:0,他引:1
研制了微囊型鸡球虫疫苗并对其免疫效果进行探讨。结果表明,强毒微囊组获得的饲养效果最好,其相对增重率和相对饲料转换率分别为104.8%和100%;弱毒水剂组为74.1%和136%,而弱毒微囊组为49.4%和188%。强毒微囊组对球虫病的控制效果也明显好于其他组,其发病率、病变记分、血便记分分别为20%,6分和3分,而弱毒水剂组和弱毒微囊组分别为40%、10分、7分和50%、18分、8分。所研制的这种新型微囊球虫疫苗,具有使用方便,节省人力物力;疫苗大小适中,流动性好容易与小鸡饲料混合均匀等优点。由于微囊型球虫疫苗投服方便,因此能适合各种规模的鸡场使用,也适合鸡场进行多次或长期免疫使用。这种微囊剂型球虫疫苗的进一步完善和推广应用,可为我国鸡球虫病的免疫预防提供新的剂型。 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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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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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