Comparison of the efficacy of a subunit and a live streptomycin-dependent porcine pleuropneumonia vaccine.
OBJECTIVE
To evaluate the efficacy of two new-generation porcine pleuropneumonia vaccines when challenged with Australian isolates of Actinobacillus pleuropneumoniae of serovars 1 and 15.


METHODS
The Porcilis APP vaccine and an experimental streptomycin-dependent strain of A pleuropneumoniae were evaluated in a standardised pen trial. Each vaccine/challenge group consisted of 10 pigs.


RESULTS
With the serovar 1 challenge, the Porcilis APP vaccine and the live vaccine, compared with the control group, gave significant protection in terms of clinical signs, lung lesions, re-isolation scores and average daily gain (ADG) postchallenge. Only the Porcilis APP vaccine provided significant protection against mortality. In the serovar 15 challenged pigs, the only significant difference detected was that the Porcilis APP vaccinated pigs had a better postchallenge ADG than the controls. None of the Porcilis APP vaccinated pigs showed signs of depression postvaccination and none were euthanased after challenge with either serovar 1 or 15. The pigs vaccinated with the live vaccine showed obvious depression after each vaccination and a total of 3 pigs were euthanased after challenge (one with serovar 1 and two with serovar 15).


CONCLUSIONS
Both of the vaccines provided significant protection against a severe challenge with serovar 1 A pleuropneumoniae. Neither vaccine was effective against a serovar 15 A pleuropneumoniae challenge. There was evidence that the Porcilis APP vaccine did provide some protection against the serovar 15 challenge because the ADG, after challenge of pigs given this vaccine, was greater than the control pigs.
Tumamao
J Q
JQ
Agency for Food and Fibre Sciences, Animal Research Institute, Queensland Department of Primary Industries, Yeerongpilly, Queensland 4105. yellowcocka2@yahoo.com
Bowles
R E
RE
van den Bosch
H
H
Klaasen
H L B M
HL
Fenwick
B W
BW
Storie
G J
GJ
Blackall
P J
PJ
D000189:Actinobacillus Infections / Q000517:prevention & control / Q000662:veterinary*; D016977:Actinobacillus pleuropneumoniae / Q000187:drug effects / Q000276:immunology*; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001428:Bacterial Vaccines / Q000627:therapeutic use*; D008826:Microbial Sensitivity Tests; D011001:Pleuropneumonia / Q000517:prevention & control / Q000662:veterinary*; D013307:Streptomycin / Q000494:pharmacology; D013552:Swine; D013553:Swine Diseases / Q000517:prevention & control*; D016896:Treatment Outcome
D000900:Anti-Bacterial Agents; D001428:Bacterial Vaccines; D013307:Streptomycin