摘要： 鸡霍乱严重威胁着养鸡业的发展，但是迄今尚未有有效菌苗用于生产。我们从本省病死鸡心血中分离出了28株多杀性巴氏杆菌，经毒力及免疫原性测定从中筛选出毒力强、免疫原性好的Sy-8421作为制苗菌株。该菌株具有典型的多杀性巴氏杆菌的菌体形态，培养特性及生化特性。2个菌可致死2公斤左右的健康家兔；3-5个菌可致死6个月龄的健康敏感鸡。该菌株在改良马丁肉汤培养后，用0.3%的甲醛灭能，以7号白油为佐剂，油、水相按一定比例制成油包水乳剂苗。该菌苗安全性好，以2倍免疫剂量接种2月龄健康鸡观察一周无任何不良反应。在实验室内用256只鸡分9批次作效力实验，其保护率为82.4%，免疫期达6个月以上。免疫后14天即可产生坚强的免疫力。该苗在0-4℃保存3.5个月仍不丧失其免疫效力，保存5个月仍保持其良好的物理性状。对3万余只鸡作中间试验获得了良好的免疫效果。

关键词: 鸡霍乱, 灭能苗, 免疫原性, 免疫效果, 免疫期

Abstract: Chichen Cholera has been threatenning the development of chicken farming seriously.But up to now there are no perfect vaccine to be applied to practice.We have saparated 28 strainsof Pasteurella multocide from the hart blood of chicken died of cholera in our province.Through determining of virulence and immunogenicity we sifted out Sy-8421 as a strain for making vaccine.The strain Sy-8421 possesses the typical character of Pasteurella multocide in organism shape and in culture and biochemical test,and has a good nature of antigen and strong virulence.Two of the strain could cause death of healthful rabbets with two kilogram weight,three to five of this strain could cause death of healthful chicken being six months old.After being cultured in improved Martin’s Bouillo,it was deactivated by 0.3% formaldehyde.Using the white oil No7 as a adjuvant,the Oil-Emulsion Vaccine was produced by emulsifying the culture and adjuvant which were mixed according to certain proportion.The Vaccine was safe,when it was inoculated to healthful chicken being two months old with diploid Imd.and no untoward effect appeared in one week.In la boratory the potency test was made for nine times using 256 chickens.The results were chat the protection rate was 82.4% and the protection time lasted more than six months.The chicken would produce strong immunity after fourteen days of inoculation.Kept in 0-4℃,after 3.5 months,the vaccine would not lose its efficacy and after five months it still maintained its good physical properties.In me-dium examination using thirty thousands chickens,the ideal result was obtained.

Key words: Chicken cholera, Deactivated vaccine, Immunogenicity, potency, Protection time