Pleuropneumonia caused by Actinobacillus pleuropneumoniae biotype 2 in growing and finishing pigs.
Actinobacillus pleuropneumoniae biotype 2 was isolated in pure culture or as the predominant isolate from the lungs of 9 growing and finishing pigs with pleuropneumonia. Gross and microscopic lesions resembled those caused by A. pleuropneumoniae biotype 1 serotypes (Nos. 1, 5, and 7) traditionally seen in the United States. The overall mortality rate for growing and finishing pigs on this 1,200-sow farrow-to-finish farm ranged from 0.37% to 0.84% per month from July 1990 to February 1991, and mortality due to respiratory disease ranged from 0.17% to 0.52% per month for the same period. This Actinobacillus species did not require V factor (no satellitism on blood agar with a Staphylococcus streak), was strongly beta-hemolytic, and demonstrated restriction fragment length polymorphisms in hybridization studies with A. suis, A. lignieresii, and A. equuli. Biochemically, the isolate most closely resembled A. pleuropneumoniae, and a DNA fragment considered specific for A. pleuropneumoniae biotypes 1 and 2 was demonstrated using polymerase chain reaction. Necrohemorrhagic pleuropneumonia similar to that caused by A. pleuropneumoniae biotype 1 was reproduced experimentally in 2 4-week-old pigs inoculated intratracheally with broth cultures of the A. pleuropneumoniae biotype 2. This study demonstrated the presence of A. pleuropneumoniae biotype 2 in the United States.
Frank
R K
RK
Department of Veterinary Diagnosis, College of Veterinary Medicine, Kansas State University, Manhattan 66502.
Chengappa
M M
MM
Oberst
R D
RD
Hennessy
K J
KJ
Henry
S C
SC
Fenwick
B
B
D000189:Actinobacillus Infections / Q000382:microbiology / Q000473:pathology / Q000662:veterinary*; D016977:Actinobacillus pleuropneumoniae / Q000235:genetics / Q000502:physiology*; D000818:Animals; D004269:DNA, Bacterial / Q000032:analysis; D008168:Lung / Q000382:microbiology / Q000473:pathology; D009693:Nucleic Acid Hybridization; D011001:Pleuropneumonia / Q000382:microbiology / Q000473:pathology / Q000662:veterinary*; D016133:Polymerase Chain Reaction; D015183:Restriction Mapping; D013552:Swine; D013553:Swine Diseases / Q000382:microbiology* / Q000473:pathology
D004269:DNA, Bacterial