Abstract: 2 pathogenic Escherichia coli strains O₈₆K₆₁ and O₄₄K₇₄ were isolated from geese colibacillosis suspect cases in Zhanjiang area, and were used to produce oil adjuvant inactivated vaccine. 20-day-old geese were inoculated with the vaccine and boosted 15 days late. The blood samples were collected and the serum agglutination antibody titers of the geese were determined to evaluate the immune efficiency, then the geese were challenged with 10¹⁰/mL pathogenic Escherichia coli to confirm the immune protection effect of the emulsion vaccine. The results showed that the vaccine above was safe and reliable, the serum antibody titers of the immunized birds came to 1∶32 and 1∶128 respectively inoculated 15 and 30 days late. Moreover, the vaccine inoculated birds were all protected against the challenge of the pathogenic bacteria, whereas the control animals exhibited visible clinical signs of colibacillosis, and the pathogenic Escherichia coli O₈₆ and O₄₄ subtypes could be isolated from the sick geese.

Key words: goose; colibacillosis; oil-adjuvant; inactivated vaccine