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鸡传染性法氏囊病野毒株的分离鉴定及河北弱毒株培育的研究 总被引:4,自引:3,他引:1
从河北省6个地区鸡传染性法氏囊病(IBD)的鸡群中,分离到6株强毒,均能使易感鸡36小时发病并死亡,发病率达60~100%,死亡率10~70%。人工感染鸡能见到与野外病例相同的病变。经血清学试验、鸡胚接种、电镜观察均证明,分离物为传染性法氏囊病毒(IBDV),其中有的毒株,毒力非常强。利用其中毒力最强的1株病毒,经鸡胚多次传代培养育成1株免疫原性好,免疫期长,免疫效果容易监测的弱毒株,经野外试验证明,该毒株是防治IBD的一个很理想的毒株。 相似文献
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应用鸡胚培养、电镜观察、血清学试验及病理组织学检查,分离与鉴定了来自河南省鸡传染性法氏囊病(IBD)免疫鸡群He1、He2、和He3三株IBDV毒株。鸡胚传代试验表明,He1和He2株连续传代到第4代出现规律性死亡和IBD病变,而He3株在第1代时鸡胚即全部死亡,且出现IBD典型鸡胚病变。He1、He2和He3毒株对易感鸡致病力有一定的差异。病死率分别为20%、10%和40%,多数为弱毒株。免疫保护试验证明,用常规的IBDV血清I型病毒株B2疫苗对He1、He2和He3毒株的免疫保护试验,与对照组相比保护率分别为0%、0%和10%。未死亡扑杀的免疫试验鸡法氏囊有不同程度的病理组织学病变,表明I型毒株疫苗对IBD基本上无免疫保护作用。所分离的毒株可能是IBDV的变异株。 相似文献
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鸡传染性法氏囊病毒强毒株的分离鉴定 总被引:2,自引:0,他引:2
从广州市郊区某鸡群送检的6周龄曾经IBDV免疫的病鸡法氏囊中分离到1株IBDV强毒。该毒株能使鸡胚于接种后36~72小时内死亡,易感鸡100%发病,50%死亡。电镜观察,该病毒颗粒直径60nm左右,无囊膜。经SDS-PAGE检测,病毒核酸有二条RNA带。 相似文献
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鸡IBD多价油乳剂灭活疫苗的研制及应用 总被引:3,自引:1,他引:2
用自行分离的IBD超强毒株COB-C1株及CUIM、UNIVAX株混合研制的多价油乳剂灭活疫苗,经实验室6批次的安全试验,共接种成鸡48只,观察21~40d均未发生异常反应,采食饮水正常,效力试验结果保护率达91.6%以上。四年来在广东佛山,河北沙河等地广泛应用60万只份,结果证实该疫苗安全有效 相似文献
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鸡传染性法氏囊病系列油乳剂组织灭活疫苗的研究 总被引:1,自引:0,他引:1
从多个地区收集的10个鸡传染性法氏囊病病毒野毒株中,筛选出超强毒TA株,采用TA株对SPF公雏攻毒,收获其法氏囊、脾脏、胸腺、肝脏、肾脏等病变组织,经处理后,与新城疫Lasota毒株、传染性支气管炎多价毒株、EDS76毒株等联合,研制出了IBD(高免免疫型)、ND-IB-IBD、ND-EDS-IBD等系列油乳剂灭活疫苗,经实验室测定,并应用于蛋种鸡、肉仔鸡常规免疫以及鸡群高免等,均取得了较好的结果 相似文献
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采用IBDV-D_(78)株种毒,由细胞培养研制的IBD弱毒疫苗,经安全试验和免疫试验,证明适合本地流行毒株,试验免疫保护率100%,对照鸡均发病。 相似文献
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表达传染性法氏囊病病毒VP2基因的重组鸡痘病毒的构建及其免疫保护性研究 总被引:1,自引:0,他引:1
以脂质体转染技术构建了表达鸡传染性法氏囊病病毒(IBDV)VP2基因的重组鸡痘病毒FPV-VP2,该病毒在鸡胚成纤维细胞及鸡体内均能稳定产生子代病毒,经翅皮下5×105PFU/羽免疫1日龄SPF鸡,免疫后4周以100LD50/羽IBDV超强毒株G株攻毒,获得了5/6的保护,但不能有效预防临床发病及法氏囊受损萎缩。实验结果证明了VP2是IBDV的宿主保护性抗原,提示T细胞介导的免疫可能在IBDV的免疫中起着较为重要的作用。本研究为IBDV重组病毒疫苗研制进行了有益探索。 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