China Animal Husbandry and Veterinary Medicine ›› 2022, Vol. 49 ›› Issue (12): 4786-4794.doi: 10.16431/j.cnki.1671-7236.2022.12.027

• Preventive Veterinary Medicine • Previous Articles     Next Articles

Isolation and Identification of Pasteurella multocida from Swine and Genetic Evolution Analysis of oppA Gene

LI Hongjie1,2, DONG Zifan1,2, CHE Yongliang2, ZHOU Lunjiang2, WANG Longbai2, BAI Dingping1   

  1. 1. College of Animal Sciences (College of Bee Science), Fujian Agriculture and Forestry University, Fuzhou 350002, China;
    2. Fujian Animal Diseases Control Technology Development Center, Institute of Animal Husbandry and Veterinary Medicine, Fujian Academy of Agricultural Sciences, Fuzhou 350013, China
  • Received:2022-06-20 Online:2022-12-05 Published:2022-12-01

Abstract: 【Objective】 The purpose of the experiment was to understand and master the epidemic situation of Pasteurella multocida (Pm) and the genetic evolution of oppA gene in pig farms in Fujian province.【Method】 In this study, bacterial isolation and culture, biochemical test, 16S rRNA PCR amplification and sequencing, PCR capsule typing, oppA gene cloning and similarity analysis, animal regression test and other methods were used to identify and analyze the isolated strains.【Result】 A total of 10 strains were isolated in this study.The isolated bacteria formed pale grayish white, moist and smooth, butter dew beads on the blood plate.The results of biochemical tests showed that the isolated strains could ferment sucrose, fructose, maltose and mannitol, and could not decompose glucose, citrate, lactose and hydrogen sulfide, which were basically consistent with the biochemical characteristics of Pasteurella multocida.The 16S rRNA sequence of the isolated strains was more than 99.9% similarity to that of Pasteurella multocida in GenBank, and 10 strains were Pasteurella multocida.PCR capsular typing showed that 6 isolates were capsular serotype A and 4 isolates were capsular serotype D.The genetic evolution tree based on oppA gene showed that all 10 isolates were located in the same branch.Animal regression test demonstrated that the mortality of infected mice was higher within 24 h (21/30), and the isolated bacteria strains had strong pathogenicity.【Conclusion】 The results indicated that the capsular serotypes of Pasteurella multocida strains in Fujian pig farms were mainly types A and D, and most of the strains were from common ancestors, which enriched the epidemiology of Pasteurella multocida and laid the foundation for the prevention and control of Pasteurella multocida infection.

Key words: swine; Pasteurella multocida; capsule typing; isolation and identification; oppA gene; genetic evolution

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