重组禽流感病毒(H5+H7)二价灭活疫苗免疫效果评估

对崇左市2017年10月至2018年9月家禽实施免疫重组禽流感病毒(H5+H7)二价灭活疫苗(H5N1亚型Re-8株+H7N9 H7-Re1株)的免疫效果进行了评估,旨在为崇左市家禽禽流感防控决策提供参考。结果表明,H5亚型禽流感免疫抗体合格率为90.35%,H7亚型禽流感免疫抗体合格率为84.94%,禽流感病毒核酸均为阴性。H5+H7免疫抗体水平较高,抗体合格的血清中,H5平均效价为8.33log2,H7平均效价为7.41log2,疫苗安全稳定,可有效抵抗当前禽流感流行毒株的侵袭。     

重组禽流感病毒（H5+H7）二价灭活疫苗的鹅免疫试验

为探究重组禽流感病毒(H5+H7)二价灭活疫苗对鹅的免疫特性,将100只27日龄四季鹅,随机分成3组:一免组40只,接种剂量0.5 mL/只;二免组40只,二次接种剂量分别为0.5 mL/只、1.5 mL/只;对照组20只,不免疫。结果显示:一免后21 d H5(Re-8株)免疫抗体平均滴度为5.85 log2,抗体合格率为85%,28 d为7 log2,抗体合格率为100%,但60 d后平均滴度降为5.95 log2;二免后7 d为7.15 log2,39 d为7.95 log2,抗体合格率均保持100%。一免后21 d H7N9免疫抗体平均滴度为5.2 log2,抗体合格率为85%,28 d为6.6 log2,抗体合格率达到100%,60 d后降为3.15 log2;二免后7 d为6.8 log2,39 d为7.05 log2,抗体合格率均保持在100%。结果表明:该疫苗能够有效刺激鹅产生免疫保护抗体,适用于鹅的禽流感免疫;为增强免疫保护效果,建议进行二次免疫。     

鸡禽流感(H5+H9)二价灭活疫苗免疫程序探讨

在每年春秋两季的重大动物疫病免疫抗体监测中,我们发现,少部分蛋鸡场的商品蛋鸡一个饲养周期只注射过2次禽流感(H5+H9)二价灭活疫苗,但在商品蛋鸡淘汰时(540日龄左右)采血检测禽流感H5亚型和H9亚型病毒免疫抗体效价,抗体合格率(≥5log2)还在90％以上.目前商品蛋鸡场疫苗防疫种类繁多,如果单用禽流感H5、H9单价灭活疫苗免疫商品蛋鸡,一个饲养周期禽流感疫苗就得注射6～8针.对此,我们用禽流感(H5+H9)二价灭活疫苗分别对两组商品蛋鸡1次性免疫和2次性免疫注射后,定期采血进行HI抗体效价跟踪检测;并对只做2次禽流感(H5+H9)二价灭活疫苗的一个商品蛋鸡场的三批蛋鸡作了禽流感免疫抗体效价和禽流感病毒抗原快速检测的调查.旨在探索一种简便、安全有效的蛋鸡禽流感的预防免疫程序.     

禽流感(H5+H9)二价灭活疫苗不同接种部位免疫肉鸽的效果比较

<正>禽流感是由A型流感病毒引起的畜禽传染病,可导致养禽业的重大经济损失,还可引发动物疫情传播,甚至威胁人类健康。肉鸽养殖作为特种养禽业,接种禽流感疫苗是防控重大动物疫病的重要措施。但是在对鸽子进行疫苗注射时,具体接种在什么地方免疫效果最好,虽有鸡的相关资料[1-3],但有关鸽的文献报告不多。为了选择科学合理的免疫途径,更好地对鸽群进行有效的免疫预防,本文进行了肉鸽禽流感灭活疫苗不同     

禽流感(H5、H9亚型)二价油乳剂灭活疫苗试验研究

本品系用A型禽流感病毒A／Ostrich／Denmark／72420／96(LPAI-H5N2)株及A／Chicken／Shanghai／1／98(H9N2)株分别接种易感鸡胚、收获感染胚液、超滤浓缩后经甲醛溶液灭活，加油佐剂混合乳化制成的油乳剂灭活疫苗。疫苗用4周龄SPF鸡作安全试验，每只鸡肌肉注射2ml，结果表明试验鸡均无全身症状和局部病变，证明疫苗安全性良好。取疫苗一羽份免疫4周龄SPF鸡作效力检验，免疫鸡全部获得保护，对照鸡全部感染或死亡。经不同免疫剂量测定，证明一羽份疫苗中至少含有8个免疫剂量。免疫干扰试验证明两种抗原具有免疫协同作用。     

重组禽流感病毒二价灭活疫苗(H5N1 Re-8株和H7N9 H7-Re1株)对雉免疫效果的研究

为评估重组禽流感病毒二价灭活疫苗(H5N1 Re-8株和H7N9 H7-Re1株)对雉的免疫保护效果,选取30日龄的雉,按照免疫程序首免后21 d,加强免疫1次,分别于接种前和接种后定期采血,分离血清,检测H5、H7亚型HI抗体滴度。结果显示,免疫前,雉血清中H5、H7亚型HI抗体滴度均为0;免疫后14 d,H5和H7亚型抗体平均滴度分别达到7.0log2和7.07log2,49 d后平均滴度达到峰值,分别为8.04log2和9.20log2;H5亚型免疫有效期可达105 d以上,H7亚型可达189 d以上。结果表明,重组禽流感病毒二价灭活疫苗(H5N1 Re-8株+H7N9 H7-Re1株)对雉具有良好的免疫保护效果且安全性良好,但疫苗免疫49 d后,H5、H7抗体效价逐渐下降,133 d后明显下降,群体免疫合格率低于70%,因此生产中推荐,30日龄首免后,51日龄和5月龄各加强免疫1次。本研究为珍稀禽的禽流感免疫疫苗选择和程序制定提供了参考。     

融水香鸭重组禽流感病毒(H5+H7)二价灭活疫苗二次免疫效果评估

选取4个融水香鸭规模场开展免疫评估试验,随机抽取该疫苗在融水香鸭二次免疫后的血清进行抗体检测,以期了解新型重组禽流感H5+H7二价灭活疫苗(H5N1 Re-8株+H7N9 Re1株)对融水香鸭的二次免疫效果、免疫保护时间。试验结果表明,该新疫苗对融水香鸭的免疫副反应极小、二次免疫对融水香鸭具有良好的免疫效果,H5和H7亚型免疫抗体水平在二次免疫后间隔21 d产生较高水平的抗体(平均HI抗体在7log2以上),且抗体维持时间长,二次免疫后间隔70 d的免疫合格率均能保持90%以上,能较好地抵抗病毒的攻击。     

蛋鸡重组高致病性禽流感H5N1(Re-1+Re-4)二价灭活疫苗免疫效果的评价

参照北京市制定的蛋鸡高致病性禽流感免疫程序,对100只蛋鸡雏免疫重组高致病性禽流感H5N1(Re-1+Re-4)二价灭活疫苗,另300只蛋鸡雏分为3组,分别免疫重组高致病性禽流感H5N1(Re-1)株、(Re-4)株灭活单苗和H5N1(Re-1)和H5N1(Re-4)作为对照。免疫应激反应观察、抗体效价检测,结果表明,二价苗与单株苗产生的抗体效价无明显差别。     

重组禽流感病毒H5亚型二价灭活疫苗免疫效果试验

禽流感是由A型流感病毒引起的一种禽类急性败血性、高度接触性传染病。对家禽进行禽流感疫苗的预防接种是我国采取防制禽流感的主要措施之一,可以通过检测血清免疫抗体的血凝抑制效价来反映机体的免疫状态和抵抗力。为了了解重组禽流感病毒H5二价灭活疫苗（H5N1,Re-4株＋Re-5株）免疫抗体的消长规律,特制定本试验方案,具体如下：     

重组禽流感病毒(H5+H7)二价灭活疫苗(H5N1 Re-8株+H7N9 H7-Re1株)对商品肉鸡的免疫效力研究

为评估重组禽流感病毒(H5+H7)二价灭活疫苗(H5N1 Re-8株+H7N9 H7-Re1株)对商品肉鸡的免疫保护效果,本研究将该疫苗按照现地免疫程序分别接种10日龄白羽肉鸡和14日龄黄羽肉鸡,疫苗接种前和接种后每周采血,分离血清,检测H5亚型Re-8株和H7亚型H7-Re1株禽流感病毒(AIV)HI抗体滴度,并在初次免疫后3周和出栏时以鼻腔感染方式分别进行攻毒试验。结果显示,免疫前,所有肉鸡血清中H7亚型H7-Re1株AIV HI抗体滴度均低于1log2,H5亚型Re-8株AIV平均HI抗体滴度分别为5.3log2(白羽肉鸡)和4.1log2(黄羽肉鸡);一次免疫的白羽肉鸡在免疫后3周至出栏时,2种亚型AIV平均HI抗体滴度在6.0log2~6.7log2;2次免疫的黄羽肉鸡在初次免疫后3周至出栏时,2种亚型AIV平均HI抗体滴度均在6.0log2以上。在一次免疫后3周时和出栏时,采用高致病性H5、H7亚型AIV攻毒后,对照组白羽肉鸡和黄羽肉鸡均全部死亡,免疫组白羽肉鸡和黄羽肉鸡均不发病、不排毒、不死亡,获得100%的免疫保护。本研究结果表明,重组AIV二价灭活疫苗对商品肉鸡具有良好的免疫效果,为该疫苗的现地应用提供了参考依据。     

猪流感(H_1N_1H_3N_2亚型)二价灭活疫苗试制报告

猪流行性感冒(swine influenza,SI)是由猪流行性感冒病毒(SIV)引起的猪的一种急性、热性和高度接触性的呼吸道传染病,其临床上以突发高热、咳嗽、呼吸困难、衰竭和死亡为特征[1].     

A single dose of inactivated oil-emulsion bivalent H5N8/H5N1 vaccine protects chickens against the lethal challenge of both highly pathogenic avian influenza viruses

In this study, two highly pathogenic avian influenza (HPAI) H5N8 viruses were isolated from chicken and geese in 2018 and 2019 (Chicken/ME-2018 and Geese/Egypt/MG4/2019). The hemagglutinin and neuraminidase gene analyses revealed their close relatedness to the clade-2.3.4.4b H5N8 viruses isolated from Egypt and Eurasian countries. A monovalent inactivated oil-emulsion vaccine containing a reassortant virus with HA gene of the Chicken/ME-2018/H5N8 strain and a bivalent vaccine containing same reassortant virus plus a previously generated reassortant H5N1 strain (CK/Eg/RG-173CAL/17). The safety of both vaccines was evaluated in specific-pathogen-free (SPF) chickens. To evaluate the efficacy of the prepared vaccines, 2-week-old SPF chickens were vaccinated with 0.5 mL of a vaccine formula containing 10⁸/EID₅₀ /dose from each strain via the subcutaneous route. Vaccinated birds were challenged with either wild-type HPAI-H5N8 or H5N1 viruses separately at 3 weeks post-vaccine. Results revealed that both vaccines induced protective hemagglutination-inhibiting (HI) antibody titers as early as 2 weeks PV (≥5.0 log₂). Vaccinated birds were protected clinically against both subtypes (100 % protection). HPAI-H5N1 virus shedding was significantly reduced in birds that were vaccinated with the bivalent vaccine; meanwhile, HPAI-H5N8 virus shedding was completely neutralized in both tracheal and cloacal swabs after 3 days post-infection in birds that had been vaccinated with either vaccine. In conclusion, the developed bivalent vaccine proved to be efficient in protecting chickens clinically and reduced virus shedding via the respiratory and digestive tracts. The applicability of the multivalent avian influenza vaccines further supported their value to facilitate vaccination programs in endemic countries.     

鸡新城疫、传染性支气管炎、禽流感(H9亚型)三联灭活苗(La Sota株+M41株+Re-9株)应用效果研究

鸡新城疫、传染性支气管炎、禽流感(H9亚型)三联灭活苗(La Sota株+M41株+Re-9株)(三联苗(Re-9株))为国内首个采用基因重组H9亚型禽流感疫苗株研制的新支流三联灭活疫苗.为研究疫苗上市后的实际应用效果,使用7日龄AA肉鸡和260日龄产蛋期蛋鸡评价三联苗(Re-9株)有效性.结果显示:肉鸡免疫后14 d...     

重组禽流感病毒H5亚型二价灭活疫苗(H5N1,Re-5+Re-4)免疫鸡和鸭后抗体消长规律

禽流感(AI)是由A型流感病毒引起的一种禽类传染病.根据致病性的不同将禽流感分为高致病性禽流感(HPAI)和低致病性禽流感(IPAI),HPAI被世界动物卫生组织(OIE)列为A类传染病,我国将其列为一类动物疫病 [1].近几年来,禽流感在世界各地反复出现,2004年亚洲发生了高致病性禽流感,2006年底和2007年初东南亚又出现疫情,并发现了人感染禽流感.我国养禽业也一直受到禽流感的威胁.因此,它不仅给畜牧业造成了巨大的损失,而且给人们的公共卫生安全带来了严重的威胁.     

Needle-free delivery of an inactivated avian influenza H5N3 virus vaccine elicits potent antibody responses in chickens

A needle-free delivery system was assessed as a route for providing quick, safe, and effective vaccination against avian influenza (AI). Two groups of chickens were vaccinated with a commercially available inactivated H5N3 virus vaccine delivered either with a needle-free device or with the conventional syringe-and-needle method recommended by the vaccine manufacturer. The kinetic aspects of seroconversion, peak antibody levels, and antibody titers were measured by a combination of an indirect enzyme-linked immunosorbent assay and the hemagglutination-inhibition test and were all found to be similar in the 2 groups of chickens. We conclude that the needle-free delivery system could result in effective immunization against H5N1 AI epidemics and pandemics in chickens.     

Immunization of broiler breeder chickens against Newcastle disease with an oil-emulsion vaccine

Antibody response was rapid and high in broiler breeder chickens receiving 1 or 2 vaccinations with oil-emulsion vaccine against Newcastle disease at 23 or at 23 and 26 weeks old. The antibody titers remained high during the 41-week experimental period. At 64 weeks old, about 41 weeks after vaccination, the geometric mean hemagglutination-inhibition antibody titer was 67 from the single vaccination, and 103 from the double vaccination. The immune response to live-virus vaccine given at 2, 9, 20, 30, 42, or 54 weeks of age via the drinking water was high, but uniformity was lacking in the antibody response in the breeders and maternal antibody response in the progeny. Maternal antibody levels in one-day-old chicks were related to the titers of antibody in the dams. Maternal antibody titers of chicks originated from breeder flocks that were vaccinated with the oil-emulsion vaccine remained high for all hatches.     

鸡新城疫-禽流感(H9亚型)二联灭活疫苗(La Sota株+HP株)的灭活试验

为了研究鸡新城疫-禽流感(H9亚型)二联灭活疫苗(La Sota株+HP株)中两种病毒的最佳甲醛灭活浓度和灭活时间,试验选取四种甲醛最终浓度0.1%、0.2%、0.4%、0.8%,分别对两种抗原进行灭活,在灭活10 h、12 h、14 h、16 h、18 h、24 h、30 h、36h、42 h分别取样,对每个样品进行灭活检验和血凝价测定。从试验结果得出,新城疫病毒(La Sota株)最适合的甲醛浓度为0.1%,灭活时间为16 h;禽流感病毒(H9亚型HP株)最适合甲醛浓度为0.1%,灭活时间为18 h。