Immunization of day-old chickens against Newcastle disease.

The avirulent Newcastle disease virus strain designated NDV-6/10, selected by B. Lomniczi at the Veterinary Medical Research Institute, Hungarian Academy of Sciences, is completely safe for day-old chickens by aerosol vaccination. Aerosol immunization using the Hungarian-made MASTERDROP generator (particle size: maximum 7 microns) caused no vaccination reactions among 206,000 chickens with different maternal antibody levels. Other vaccines given simultaneously did not significantly affect the protection elicited against Newcastle disease (ND). Almost 100% and 90% of the aerosolized chickens survived subcutaneous challenge with 10(6) LD50 NDV at 30 and 50 days old, respectively. A single immunization is sufficient for broilers; however, parent flocks should be revaccinated at 7 so 8 weeks old.     

Vaccination of cyclophosphamide-treated chickens against Newcastle disease virus infection

Newly-hatched chickens were treated with 3 mg of cyclophosphamide (CY) per day for 4 consecutive days. At 2 weeks of age, these chickens, together with a group of untreated controls, were vaccinated intranasally or subcutaneously with the La Sota strain of Newcastle disease virus (NDV). All chickens were challenged intranasally with the GB strain of NDV 2 weeks later. CY-treated, intranasally vaccinated chickens were highly resistant to NDV challenge, yet none of the chickens produced any detectable humoral antibodies to NDV; antibodies to NDV were detectable in the tracheal washings, however.     

鸡新城疫不同毒株间的交叉保护性研究

将NDV－La Sota疫苗株、NDV山东地方强毒株CY和DY以及NDV F48E8标准强毒株分别制成油乳剂灭活疫苗，免疫6周龄SPF鸡，然后分别用分离强毒株和F48E8强毒株进行攻击。结果发现，两个分离毒株之间、分离毒株与标准毒株之间、IV系疫苗株与分离毒株之间都可以得到完全交叉保护。     

The immunization of pheasants against Newcastle disease]

ND-Adsorbatvakzine "Dessau" and Lasovak are well effective and tolerated in pheasants as immuno-prophylactic methods against Newcastle disease infection. Lasovak produces higher titres of antibodies and better rates of protection. The antibodies are created quicker too and reduced more slowly. There is no correlation between the average of antibody level and rate of protection after experimental infection. Even if antibodies are not demonstrable in hemagglutination inhibition test there is still existing a satisfactory protection. After two vaccinations in the age of chickens in 3 to 4 weeks interval and repetition after always 16 weeks pheasants can be protected effectively for the rearing and breeding seasons.     

几种鸡新城疫弱毒疫苗的免疫效力试验

鸡新城疫是我国养鸡业中危害最大的疾病之一,也是影响禽产品国际贸易最 重要的禽类传染病.长期的疫病防制工作中,我们发现不管是在规模化的养殖场,还是在农 村中的个体养殖户,新城疫的防制一旦失败,鸡场所遭受的损失都是非常大的,有时则是毁 灭性的.鸡新城疫除其本身能造成鸡群严重的发病和死亡外,还常常并发或继发其他疫病的感染,此时造成的经济损失比单独发生时更加严重 [1] ,因此人们对该病的防制极其重视.     

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.     

中药口服液防治鸡新城疫临床效果试验

将筛选出具有抗病毒作用的黄芪、黄芩、板蓝根等中药制成口服液,用于鸡新城疫防治试验。结果表明,中药口服液防治鸡新城疫具有较好疗效,中药治疗组鸡死亡率极显著低于对照组,且以中药口服液疗效最佳。同时,中药治疗组可提高蛋鸡生产性能。     

Field trials of a food-based vaccine to protect village chickens against Newcastle disease

The food pellet vaccine has been shown to be effective in trials conducted under laboratory and simulated field conditions. The village chickens vaccinated with the food pellet vaccine during the field trial were protected against virulent Newcastle disease virus. The efficacy of the food pellet vaccine in the field was evaluated by challenge trial in which 60 per cent protection was obtained, or by monitoring the incidence of Newcastle disease in vaccinated and unvaccinated birds. There was no report of Newcastle disease outbreaks in the vaccinated birds during the two-year period of the field trial. The ease in administering the food pellet vaccine makes it readily accepted by the farmers.