Pleuropneumonia in swine caused by Haemophilus parahaemolyticus. A study of the epidemiology of the infection
Nielsen, R.; Mandrup, M.
Nordisk Veterinaermedicin 29(11): 465-473
1977
ISSN/ISBN: 0029-1579 PMID: 593808 Document Number: 116658
None of 30 serologically negative pigs in an open herd contracted the infection when exposed to contact with two pigs that became positive after inoculation with parahaemolyticus three weeks earlier. After aerosol infection had been applied in the building an acute outbreak affecting all 16 pigs developed in less than 24 h. Following recovery, most of the pigs became serologically positive, and when 30 negative pigs were introduced 7 weeks later, antibody response occurred in three of them. Persistence of the organism in pigs that had been infected during the acute outbreak was confirmed at slaughter (isolation from the tonsils of two of these pigs). Most serum titres persisted for several months, but some animals showed just a transient antibody response.