球康对兔球虫病的疗效评价

将40只30~45日龄健康日本大耳白兔随机分成4组,即不感染不给药组()、感染不给药组()、盐霉素组()和球康组(),每组10只。除组兔外,其余3组试验兔均按每100g体质量口服接种球虫卵囊5×104个。根据临床症状、病理变化、增重及OPG值等指标进行药物疗效判定,并对感染球虫前后血液学数值的动态变化进行测定。结果表明,球康能减轻家兔感染球虫后的肠道出血,调节机体非特异性免疫应答,对球虫病的治愈率达100%。     

Efficacy for a New Live Attenuated Salmonella Enteritidis Vaccine Candidate to Reduce Internal Egg Contamination

To evaluate the efficacy of a novel attenuated Salmonella Enteritidis (△lon△cpxR) vaccine candidate (JOL919), chickens were immunized through oral and intramuscular routes to reduce egg contamination against S. Enteritidis challenge. Birds were orally immunized with JOL919 on the first day of life and were subsequently boosted in the 6th and 16th weeks through oral (group B) or intramuscular (group C) route, while control birds were unimmunized (group A). The chickens of all groups were challenged intravenously with the virulent S. Enteritidis strain in the 24th week. The immunized groups B and C showed significantly higher plasma IgG and intestinal secretory IgA levels as compared to those of the control group. The lymphocyte proliferation response and CD45⁺CD3⁺ T‐cell number in the peripheral blood of the groups B and C were significantly increased. In addition, the egg contamination rates were significantly lower in the group B (0%, 10.7% and 0%) and the group C (3.6%, 14.3% and 3.6%) as compared to the group A (28.6%, 42.8% and 28.6%) in the 1st, 2nd and 3rd weeks post‐challenge. All animals in the groups B and C showed lower organ lesion scores in the liver and spleen and lower bacterial counts in the liver, spleen and ovary at the 3rd week post‐challenge. These results indicate that this vaccine candidate can be an efficient tool for prevention of Salmonella infections by inducing protective humoral and cellular immune responses. In addition, this vaccine did not prevent egg contamination, but did appear to reduce incidence. Booster immunizations, especially via oral administration route, showed an efficient protection against internal egg contamination with S. Enteritidis.     

我国猪瘟疫苗效力检验的替代方法研究与应用进展

我国兽药典中现行的猪瘟疫苗效力检验方法存在试验成本较高、周期较长、操作较繁琐、重复性较差、敏感性较低等缺点,随着分子生物学与免疫学技术的日臻发展与应用,猪瘟疫苗效力检验的新兴替代检验方法不断发展和完善。论文就我国近年来针对猪瘟疫苗毒种、半成品、成品效力检验的新兴分子生物学和免疫学检测方法的研究与应用进展做一简要综述,旨在为提升我国猪瘟疫苗效力检验水平提供合理的科学依据。     

免疫剂量和母源抗体对禽流感重组鸡痘病毒活载体疫苗免疫效力的影响

利用表达 H 5亚型禽流感病毒 (AIV)血凝素基因的重组鸡痘病毒 (r FPV- HA)以不同剂量免疫 1日龄 SPF鸡、有或无母源抗体 (FPV、AIV H5)的商品鸡 ,并于免疫后 2 1d利用同亚型 AIV通过肌肉注射进行致死性攻击 ,通过检测免疫后 HI抗体应答、比较攻毒后发病率和死亡率评价免疫剂量和母源抗体对 r FPV- HA免疫效力的影响。结果发现 ,免疫后 2 1d,15 %～ 2 0 %的 SPF鸡和无母源抗体商品鸡可检出 HI抗体 ,而含母源抗体商品鸡检测不到 HI抗体。利用H5亚型 AIV致死性攻击后 ,10 3～ 10 6 PFU的 r FPV- HA可保护 95 %～ 10 0 %的 SPF鸡和无母源抗体商品鸡抵御强毒攻击 ,使之免于发病和死亡 ;而不同剂量 r FPV- HA接种的含母源抗体商品鸡有 80 %～ 90 %发病和死亡。结果表明 ,在较宽的免疫剂量范围内 ,r FPV- HA对 SPF鸡和无母源抗体商品鸡可提供良好的保护 ,显示出一定的应用前景 ;母源抗体影响 r FPV- HA诱导的免疫应答 ,且提高免疫剂量亦不能克服其干扰作用 ,这提示在实际应用中需优化免疫程序 ,避免母源抗体干扰。     

替米考星治疗人工感染巴氏杆菌病仔猪试验

研究了国产替米考星注射用药对人工感染多杀性巴氏杆菌病猪的治疗效果,用断奶仔猪进行试验,为临床使用提供了依据.结果表明,替米考星治疗急性猪肺疫效果确实, 推荐剂量为10 mg/kg体重.     

复方蒲公英注射液对猪弓形体病的疗效观察

猪弓型虫病又称猪弓形体病、弓原虫病。是由垄地弓行虫寄生于各种动物的细胞内引起的一种人、畜共惠的原虫病,该病以患病动物的高热,呼吸及神经系统症状,动物死亡和妊娠动物的流产、死胎、胎儿畸形为特征。暴发弓形体病时,可使整个猪场发病,死亡率可高达60％以上。目前全国各地均有本病的存在,给人类健康和畜牧业发展带来了很大的危害和威胁。本试验对猪临床发病病例经过流行病学调查、临床症状及剖检变化观察、最后经过实验室检查确诊为猪弓形虫病。应用复方蒲公英注射液进行治疗,结果有效率为100％。治愈率为95％,与对照组差异显著（P〈005）,可以在临床推广使用。     

减毒鸡沙门菌疫苗株97A的免疫保护效力试验

减毒沙门菌疫苗株97A免疫鸡经鸡沙门菌强毒株Sg9攻击后,对免疫攻毒组和攻毒对照组鸡进行病理学检查和细菌分离,以进一步评价97A疫苗的免疫保护效力。结果表明,免疫攻毒组鸡肝脏、肺脏和肾脏等实质器官仅有轻到中度的炎症反应,而攻毒对照组鸡则表现出了严重的组织病理学变化,同时减毒鸡沙门菌疫苗株97A能显著地限制强毒株在鸡体内的定居和增殖,显示出了良好的免疫保护效力。     

Combination of cell culture and quantitative PCR (cc–qPCR) to assess disinfectants efficacy on Cryptosporidium oocysts under standardized conditions

Oocysts of Cryptosporidium parvum are resistant to environmental conditions and many disinfectants. A combination of cell culture and quantitative real time PCR (cc–qPCR) is established for evaluation of anticoccidial disinfectants against C. parvum. C. parvum oocysts were treated with disinfectants, washed and oocysts were incubated with HCT-8 cell monolayers in the presence of excystation medium for 3 h. Subsequently, unbound parasites were removed by washing with growing medium and the infected monolayers were further maintained in fresh growing medium for 48 h. Genomic DNA was extracted from each sample and qPCR performed targeting a specific sequence of the 70 kDa heat shock protein gene in order to quantify development. Treatment of oocysts with cresolic disinfectants demonstrated dose dependent reduction of viability of oocysts. More than 98% inactivations were recorded with at least 2% concentration of cresolic disinfectants after 2 h of treatment. Bleach (sodium hypochlorite) at 6% solution induced 92.7% inactivation of C. parvum oocysts after 2 h. Thermally treated oocysts (56 and 70 °C for 20 min) demonstrated complete inactivation, whereas at 38 °C no inactivation was observed. Application of Neopredisan^® 135-1 and Aldecoc^® TGE (4% for 2 h) as recommended according to the current guidelines stipulated by DVG (German Veterinary Society) consistently inactivated more than 99.5% of oocysts. The suggested cc–qPCR method appeared to be suited for standardized testing of inactivation measures, particularly for evaluation of chemical disinfectants and thus cc–qPCR is proposed as an alternative to the established chicken infectivity model for Eimeria tenella for testing anticoccidial disinfectants. A minimum inactivation of 99.5% in cc–qPCR model is claimed as a suitable threshold for certification of chemical products for disinfection of coccidia oocysts.     

以 Balb／c 小鼠为动物模型的 PCV-2疫苗效力检验方法的建立

为建立以Balb／c小鼠为动物模型的 PCV-2疫苗免疫效力检验方法,选取4周龄 SPF级雌性Balb／c 小鼠20只,随机分成4组（Ⅰ、Ⅱ、Ⅲ、Ⅳ组）,每组5只,Ⅰ、Ⅱ和Ⅲ组分别背部皮下1点,背部皮下2点和背部皮下、腿部肌肉2点接种 PCV-2疫苗0．1、0．2、0．2 mL／只,Ⅳ组空白对照组不接种;各免疫组分别于首免疫后7、14、21 d 加强免疫一次,免疫后7、10、14、21、28、35、42 d 采血分离血清,用 ELISA 方法测定PCV-2特异性抗体,确定最佳免疫途径和免疫剂量。另选取4周龄 SPF 级雌性 Balb／c 小鼠,随机分成免疫组、攻毒对照组和健康对照组,免疫组和攻毒对照组于二免后14 d 用 PCV-2强毒株进行攻毒,比较各试验组小鼠在临床症状、病理变化、相对日增重、PCV-2核酸载量等方面差异性,确定小鼠动物模型检测指标。抗体测定表明,一免背部皮下、腿部肌肉2点免疫0．2 mL／只,间隔21 d 加强免疫为最佳免疫程序,免疫后35 d 抗体水平达到峰值,显著高于Ⅰ和Ⅱ组。对照组小鼠免疫攻毒后出现消瘦、被毛凌乱、精神紧张等临床症状,淋巴结肿胀、出血、肺脏出血等病理变化,相对日增重显著降低,PCV-2核酸载量差异在103以上等临床变化。本研究以 Balb／c 小鼠为动物模型建立了 PCV-2疫苗免疫效力检验方法,优化了小鼠免疫途径及剂量,确定了相应的检测指标及技术参数,为 PCV-2疫苗免疫效力检验奠定了基础。