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禽流感疫苗抗原浓缩工艺的研究 总被引：1，自引：0，他引：1
为了提升禽流感疫苗中的抗原效价,本研究采用密理博公司的切向流超滤系统,选用不同孔径的超滤膜和浓缩倍数对禽流感病毒(H9N2亚型,HP株)进行浓缩,观察HA和EID50的变化.结果显示:膜包孔径越大,病毒透过越多,但膜包孔径过小,浓缩时间长;随着浓缩倍数增加,HA和EID50均呈正相关增长,但高浓缩倍数耗时较长.说明禽流感疫苗生产中应根据抗原相对分子质量、HA、EID50和生产效率选择合适的超滤膜孔径和浓缩倍数. 相似文献
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《国外畜牧学(猪与禽)》2015,(11)
通过试验检测鸡场常用的高端和低端两种新城疫(lasota株)活疫苗初始病毒含量(EID50/羽份),并模拟饮水免疫,将两种疫苗稀释后分别放在10℃、20℃和30℃温度中水浴中1 h、2 h和3 h,检测在不同温度、不同水浴时间下疫苗病毒含量(EID50/羽份)的变化,为生产中饮水免疫提供理论依据。结果表明:高端和低端新城疫活疫苗初始病毒含量分别为106.5 EID50/羽份和106.0 EID6.050/羽份,高端疫苗病毒含量高于国家标准(10 EID50/羽份)3.2倍,低端疫苗和国家标准一致;放置在水浴中的疫苗病毒含量随着时间增加呈下降趋势,水温越高下降越快;高端疫苗在10℃3 h、20℃2 h和30℃1 h条件下可以保证病毒含量(EID50/羽份)不低于国家标准,而低端疫苗无论溶解在哪个温度的水中后,进行免疫的病毒含量(EID50/羽份)都低于国家标准。 相似文献
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为研究由悬浮培养的MDCK细胞制备的H9亚型AIV抗原所制备的灭活疫苗的免疫剂量,在生物反应器中悬浮培养MDCK细胞,接种H9亚型禽流感病毒WD98和HN04种毒,收获抗原液,以2种抗原液分别制备2个毒株的单价油佐剂灭活疫苗。每种疫苗均按照0.3、0.2、0.1、0.05mL/只(107.5 EID50/只~105.52 EID50/只)的剂量接种21日龄SPF鸡,免疫接种后3周采血测定AIV的HI抗体,采血后分别用与制苗株同源的H9亚型AIV种毒静脉注射攻毒,测定疫苗保护率。2种疫苗不同剂量免疫接种后21d的AIV HI抗体水平达到3.8log2~5.6log2,对照组鸡AIV HI抗体均为0log2。攻毒试验证实,以105.52 EID50/只~107.5 EID50/只剂量进行免疫接种,免疫鸡只获得了80%以上的保护。按照兽药典H9亚型禽流感疫苗攻毒保护率90%为合格的标准,悬浮培养MDCK细胞制备的H9亚型禽流感疫苗的最小免疫接种剂量为106.82 EID50/只。 相似文献
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以10^3.0、10^4.0、10^5.0 EID503个不同剂量接种非免疫鸡胚,收获鸡胚液,病毒含量测定结果显示,以10^3.0-10^4.0～EID50剂量接种的鸡胚收获的抗原含量高。用该优化方法繁殖了一批新城疫抗原,采用截留分子量为100kD的浓缩滤膜对新城疫抗原进行浓缩,对不同浓缩倍数的新城疫抗原制备疫苗进行了免疫效力试验。结果表明,以新城疫3倍浓缩抗原制备疫苗,以5μL剂量（现有相关产品效力检验的1／4剂量）免疫SPF鸡,即可达到现有同类产品的效力检验质量标准,高抗体水平至少可以维持35d。本研究为进一步研制新城疫灭活浓缩疫苗用于低剂量免疫肉鸡提供了基础。 相似文献
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为了探讨悬浮培养和鸡胚尿囊液培养得到的H9亚型禽流感病毒(AIV)抗原制备的疫苗的免疫效力,试验用3株H9亚型AIV株分别接种微载体悬浮培养的MDCK细胞制备3种悬浮培养的细胞疫苗抗原,以3株H9亚型AIV株接种10日龄SPF鸡胚制备3种鸡胚尿囊液抗原,测定6种抗原液HA效价和鸡胚半数感染量(EID50);分别使用6种抗原液制备灭活疫苗,免疫21日龄SPF鸡,并在免疫后第21天采血测定HI抗体水平,采血后进行攻毒并在攻毒后第5天进行病毒分离试验。结果表明:两种方式制备的AIV抗原HA效价为7~9 lb,鸡胚半数感染量为1×106.9~7.9EID50,疫苗免疫后第21天用同源毒株作为工作抗原测定的免疫鸡HI效价差异不大,用异源毒株测定时有一定差异;两种方法得到的抗原制备的疫苗均能获得很好攻毒保护。 相似文献
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试验用SPF鸡胚和普通鸡胚分别测定鸡新城疫LaSota两种不同毒株的EID50:LaSota株Ⅰ在SPF鸡胚的EID50为10-7.75,普通鸡胚的EID50为10-7.25;LaSota株Ⅱ在SPF鸡胚的EID50为10-4.75,普通鸡胚的EID50为10-4.25。两种不同LaSota毒株在SPF鸡胚中的毒力普遍比在普通鸡胚中的毒力强,说明鸡胚母源抗体能影响鸡新城疫病毒的增殖,进而指导疫苗的生产。试验用SPF鸡胚和普通鸡胚分别测定鸡新城疫LaSota两种不同毒株的EID50:LaSota株Ⅰ在SPF鸡胚的EID50为10-7.75,普通鸡胚的EID50为10-7.25;LaSota株Ⅱ在SPF鸡胚的EID50为10-4.75,普通鸡胚的EID50为10-4.25。两种不同LaSota毒株在SPF鸡胚中的毒力普遍比在普通鸡胚中的毒力强,说明鸡胚母源抗体能影响鸡新城疫病毒的增殖,进而指导疫苗的生产。 相似文献
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Chickens varying in age from ten days to five years were vaccinated with 10(1.3), 10(2.3) and 10(3.3) EID50 per bird of a commercial infectious laryngotracheitis drinking water vaccine. The vaccine gave no adverse reaction in the dose range tested. Five weeks after administration of 10(3.3) EID50 per bird 70% were protected against the intratracheal challenge with virulent infectious laryngotracheitis virus. Doses of 10(1.3) and 10(2.3) EID50 per bird did not give protection. No serological response could be detected by the neutralization test even in the group that had received 10(3.3) EID50 per bird. No contact spread of virus was detected from 14 days post-vaccination. Carriers of vaccine virus could not be demonstrated. 相似文献
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Conventional Newcastle disease vaccines are not suitable for application to village chickens in tropical countries of Asia. Trials with food-based vaccines are being initiated and the following experiments were performed to evaluate oral vaccination with Newcastle disease virus. Experimental chickens were vaccinated orally with the avirulent V4 strain of Newcastle disease virus and haemagglutination-inhibition antibody responses were measured. V4 virus was introduced into the crop by tube and total faecal output was collected daily and assayed for Newcastle disease virus. Virus was recovered on Days 5 and 6 after vaccination from most chickens that had received 10(7.4) and 10(6.4) 50% egg-infectious doses (EID50) of virus. There was no recovery of virus from birds receiving a lower dose of vaccine. Groups of chickens kept in cages with wire floors were given various doses of vaccine into the crop. Higher antibody titres were achieved with higher doses of virus. This dose responsiveness was not observed when various doses of vaccine were presented on food pellets and the groups of chickens were kept on concrete floors. Similar antibody responses were then seen with nominal doses of 10(5.2) and 10(8.2) EID50 per bird, possibly as a result of excretion and re-ingestion of the vaccine virus. Spread of the vaccine virus was demonstrated when control chickens and chickens receiving 10(7.7) EID50 of V4 virus on food pellets were housed together on a concrete floor. Similar antibody titres were achieved in both vaccinated and in-contact chickens. 相似文献
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The virus titers of seven commercial B1 strain Newcastle disease vaccines were evaluated. A 2 log difference in virus content was found between the vaccine with the highest titer (10(8.8) EID 50/ml) and the one with the lowest titer (10(6.8) EID 50/ml). Broiler chickens were vaccinated with the high- and low-titered vaccines to compare hemagglutination-inhibition (HI) antibody and challenge responses. The effect of vaccination at different ages on the HI titers was also examined. There were no significant differences between vaccine groups in HI antibody response or resistance to challenge. However, the high-titered vaccine may provide a margin of safety with the currently used methods of mass vaccination. 相似文献
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对不同保存年代的鸡新城疫活疫苗种毒HB1株（Ⅱ系）和F株（Ⅲ系）各3批进行了病毒含量测定和免疫原性试验。3批不同保存年代的鸡新城疫病毒HB1株和F株病毒含量均≥108.4EID50/0.1 mL,最小免疫量均≤2500 EID50。结果表明,鸡新城疫病毒HB1株和F株毒种在-70℃分别保存16年和19年,病毒含量和免疫原性仍符合《中华人民共和国兽用生物制品规程》（二〇〇〇年版）规定。 相似文献
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The susceptibility, immune response, and protection to challenge after vaccination in racing pigeons (Columbia livia) was assessed with the 2002-2003 exotic Newcastle disease (END) virus responsible for the most recent major outbreak in Southern California. Immunologically na?ve pigeons appeared resistant to disease, regardless of dose, after a natural route of exposure. Twenty percent morbidity was observed in each group of birds receiving between 10(2.1) and 10(8.1) 50% embryo infectious dose (EID50) per bird, with one bird succumbing to challenge in the 10(8.1) EID50/bird group at day 12 postinoculation. Although resistant to disease, birds in all groups continued to shed virus from either oral or cloacal route at the end of the 14-day sampling period, and seroconversion was only observed in birds receiving > or =10(6.1) EID50. Single or double vaccination of juvenile and adult birds with pigeon paramyxovirus virus type 1 (PPMV-1) vaccine followed by END challenge with 10(6.1) EID50/bird decreased the duration, incidence, and viral load. A positive correlation was observed between the presence of hemagglutination-inhibiting antibody titers at challenge and decreased viral shedding. Overt clinical signs of disease were not observed in any PPMV-1-vaccinated birds after challenge. 相似文献
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鸡传染性支气管炎（嗜肾型）活疫苗（W93株）的研究 总被引：1，自引：0，他引：1
从国内发病鸡群中分离到鸡传染性支气管炎（嗜肾型）病毒（NIBV），并培育成弱毒W93株。自1994年，我们对该毒株进行了鉴定和活疫苗的研制，结果证明W93株具有特异性强，良好的安全性和免疫原性，病毒含量不低于10^8.0EID50/0.1ml.通过实验室试验和现场应用证明，具有较高的免疫保护率和安全性。 相似文献
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Cross-protective properties of infectious bursal disease viruses (IBDVs) were studied. Viruses represented different subtypes of serotype 1, including recently isolated viruses (variants), and a serotype 2 virus. Chickens were vaccinated at 3 weeks of age with inactivated vaccines containing 10(5), 10(6), 10(7), or 10(8) mean tissue-culture infectious dose of a given virus and challenged 2 weeks later using either 10(2) or 10(3.5) mean embryo infectious dose (EID50) of either a standard virus or a variant serotype 1 virus. Protection was evaluated at 5 and 10 days post-challenge, based on gross and microscopic lesions, body weight, and bursa/body-weight ratios. The serotype 2 virus did not confer protection on birds challenged with the serotype 1 viruses. Vaccines made of variant viruses at the low doses protected chickens challenged with the high or low doses of either the standard or the variant viruses. Vaccines made of the standard or variant strains at low doses protected against high or low challenge doses of the standard strain. Vaccines made of the high dose of any of the standard strains protected chickens against the variant virus when the low challenge dose (10(2) EID50) was used, but not when the high challenge dose (10(3.5) EID50) was used. The lowest dose of the standard viruses vaccines required to confer protection against the variant virus varied depending on the strain. Results indicated that protection depended on the strain and dose of both the vaccine and challenge viruses and that the variant strains and standard strains share a common protective antigen(s). 相似文献
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House flies (Musca domestica) and little house flies (Fannia canicularis) were examined for their ability to take up and harbor a velogenic strain of exotic Newcastle disease virus (ENDV) (family Paramyxoviridae, genus Avulavirus). Laboratory-reared flies were allowed to feed on evaporated milk containing ENDV at a virus concentration of 10(8.3) egg infectious dose (EID)50/0.1 ml or on poultry feces containing an ENDV titer of 10(5.8) EID50/0.1 g. Flies exposed to either infectious food source for 24 hr became transiently infected with virus. Virus persisted predominantly in the mid- and hindgut, with relatively little virus isolated from the remainder of the fly body. Virus persisted similarly in both fly species that were fed evaporated milk containing ENDV, with a maximum ENDV titer of 10(5.98) EID50/fly for the house fly and 10(4.78) EID50/fly for the little house fly at 1 day postexposure; titers decreased on subsequent days to 10(2.38) EID50/fly for house fly and > or = 1 EID50/fly for little house fly at 5 days postexposure. Both fly species acquired viral titers greater than the infective dose for a susceptible chicken (10(3.0) EID50-10(4.0) EID50). In addition, flies fed evaporated milk containing a high titer of ENDV maintained viral titers above the infective dose for up to 4 days postexposure to the infectious food source. Flies fed on infective feces retained a chicken infective dose for only one day. The decrease in viral titer over time was significantly explained by logistic regression for both fly species (P < 0.05). The slope of the regression line was not different for the two fly species (P < 0.05), indicating a similar rate of virus loss. 相似文献