【作者】 李舫；

【导师】 陈溥言；

【作者基本信息】 南京农业大学 ， 兽医学， 2004， 硕士

【摘要】 采用鸡胚尿囊腔接种法从山东省的潍坊、聊城、青岛、烟台、滨州、淄博、德州、荷泽、临沂、泰安、济宁、东营等地发病严重鸡场分离到38株有血凝性的病毒，经HA、HI试验及血清中和试验，结果32株被确定为鸡新城疫病毒。参照国际上规定的新城疫病毒毒力判定的标准及其方法，测定32株鸡新城疫病毒的鸡胚最小致死量平均死亡时间(MDT)为37.7-57.9h；1日龄雏鸡脑内接种致病指数(ICPI)1.68-1.89；6周龄鸡静脉注射致病指数(IVPI)为2.31-2.70。测定结果表明：32株鸡新城疫病毒均为鸡新城疫病毒强毒。用32株分离的鸡新城疫病毒接种30日龄新城疫非免疫鸡，其发病率为100％，病死率为70％-100％。 调查统计结果表明：鸡新城疫一直是影响养禽业的最主要的疫病之一，在山东省的潍坊、聊城、青岛、烟台、滨州、淄博、德州、荷泽、临沂、泰安、济宁等地也一直存在不同程度的流行，且一年四季均有发生。其中冬天出现的频率最高(17／32)。鸡新城疫可使不同品种鸡发病，但不同品种的发病鸡群死亡率不同。不同日龄的鸡均可发生鸡新城疫，但其主要的发病日龄相对集中在20-40日龄和180-260日龄，10日龄以内的雏鸡亦可发病，其死亡率较高，而且发病鸡的发病日龄越小，死亡率越高，10日龄内的鸡的死亡率可超过70％。蛋鸡群多在180-260日龄发病，产蛋下降率多在20％-50％之间，死亡率多在0.1％-5％之间，个别产蛋鸡群的死亡率超过30％。 我们通过分析32个鸡场发生鸡新城疫的可能原因，制定了鸡新城疫综合性防制对策。在20个曾发生过鸡新城疫的鸡场推广使用。使用结果表明：试验鸡场采用综合防制对策后，发生鸡新城疫的次数显著减少，疾病发生率下降了81.8％。所以对新城疫的控制，采取综合防制措施是有效的。更多还原

【Abstract】 Thirty-eight virus strains were isolated from affected chicks in Weifang, Qingdao, Yantai, Binzhou, Zibo, Dezhou, Heze, Linyi of Shangdong province using specific pathogen free (SPF) chick embryos These isolates are able to agglutinate chick red blood cell. Thirty-two virus strains of them were characterized as Newcastle disease virus (NDV) by hemagglutination (HA) /hemagglutination-inhibition (HI) test. The biological characteristics of these viruses were determined by measuring the mean death time of chick embryos (MDT) , the intracerebral pathogenicity index in day-old chicks (ICPI) and the intravenous pathgenicity index in 6-week-old chickens (IVPI) at the virulence of NDV. The results indicated that these isolates of Newcastle disease virus were high virulent Newcastle disease virus. 30-day-old unimmunized chicks were inoculated with these isolates of Newcastle disease virus . As a result, all the tested chick showed a 100% morbidity and a 70%~ 100% mortality respectively.The epidemiological results showed that Newcastle disease outbroks in Weifang, Qingdao, Yantai, Binzhou, Zibo, Dezhou, Heze, Linyi of Shangdong province. Newcastle disease could infect different ages and species chick in all seasons, but it was most popular in winter and in 20-40 or 180-260 days old chicks, the younger the chicks were, the higher mortality rates was; the rates to produce eggs of the chicks usually redudcd as 20%~50% , the mortality rates of adult chicks was0.1%-5%.The causes of Newcastle disease outbreaking in some areas of Shangdong province were analysed and a rule of biosecurity against it were made. The rule was applied in 20 farms where Newcastle disease have been found before. The results indicated that the rule was applicable. The reduction rates was 81.8%.更多还原