Effect of endobronchial challenge with Actinobacillus pleuropneumoniae serotype 9 of pigs vaccinated with a vaccine containing Apx toxins and transferrin-binding proteins.
The efficacy of a subunit vaccine containing the Apx toxins of Actinobacillus pleuropneumoniae and transferrin-binding proteins was determined. Ten pigs were vaccinated twice with the vaccine. Eight control animals were injected twice with a saline solution. Three weeks after the second vaccination, all pigs were endobronchially inoculated with 10(6.5) colony-forming units (CFU) of an A. pleuropneumoniae serotype 9 strain. In the vaccine group, none of the pigs died after inoculation. Only one pig of the control group survived challenge. Surviving pigs were killed at 7 days after challenge. The mean percentage of affected lung tissue was 64% in the control group and 17% in the vaccine group. Actinobacillus pleuropneumoniae was isolated from the lungs of all animals. The mean bacterial titres of the caudal lung lobes were 5.0 x 10(8) CFU/g in the control group and 3.0 x 10(6) CFU/g in the vaccine group. It was concluded that the vaccine induced partial protection against severe challenge.
Department of Pathology, Bacteriology and Poultry Diseases, Faculty of Veterinary Medicine, University of Gent, Merelbeke, Belgium. Ingrid.Vanoverbeke@rug.ac.be
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Van Overbeke
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Chiers
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Ducatelle
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Haesebrouck
D000189:Actinobacillus Infections / Q000517:prevention & control / Q000662:veterinary*; D016977:Actinobacillus pleuropneumoniae / Q000145:classification / Q000276:immunology*; D000818:Animals; D001428:Bacterial Vaccines; D002352:Carrier Proteins; D033862:Iron-Binding Proteins; D008168:Lung / Q000382:microbiology; D018410:Pneumonia, Bacterial / Q000517:prevention & control / Q000662:veterinary*; D013552:Swine; D013553:Swine Diseases / Q000517:prevention & control*; D033863:Transferrin-Binding Proteins; D022223:Vaccines, Subunit
D001428:Bacterial Vaccines; D002352:Carrier Proteins; D033862:Iron-Binding Proteins; D033863:Transferrin-Binding Proteins; D022223:Vaccines, Subunit