Associations between pathogens in healthy pigs and pigs with pneumonia
1Clinic for Swine, Infectious and Epidemic Diseases, Ludwig-Maximilians University, Sonnenstrasse 16, 85764 Oberschleissheim, Germany.
The Veterinary Record
|March 4, 2008
Summary
Porcine respiratory disease is often caused by multiple pathogens. This study found frequent co-infections, particularly involving porcine circovirus type 2 (PCV-2) and alpha-hemolytic streptococci, in pigs with respiratory illness.
Area of Science:
- Veterinary Medicine
- Animal Pathology
- Microbiology
Background:
- Pneumonia and bronchopneumonia are significant causes of morbidity and mortality in swine.
- Understanding the etiological agents and their interactions is crucial for effective disease management.
Purpose of the Study:
- To investigate the associations between various bacterial and viral pathogens in the development of pneumonia and bronchopneumonia in pigs.
- To determine the prevalence of specific pathogens in pigs with and without clinical signs of respiratory disease.
Main Methods:
- Bronchoalveolar lavage fluid samples were collected from 100 healthy pigs and 239 pigs with respiratory signs.
- Samples were analyzed for the presence of Mycoplasma hyopneumoniae, Mycoplasma hyorhinis, PRRSV (US and EU types), PCV-2, Influenza A, Streptococcus species (alpha- and beta-hemolytic), Pasteurella multocida, Bordetella bronchiseptica, Haemophilus parasuis, and Actinobacillus pleuropneumoniae.
Main Results:
- Pathogens were detected more frequently in pigs with clinical signs compared to healthy controls.
- Porcine circovirus type 2 (PCV-2) and alpha-hemolytic streptococci were the most frequently detected pathogens.
- Significant associations were observed between multiple pathogens in pigs with clinical signs, indicating frequent co-infections.
Conclusions:
- Co-infections with multiple pathogens are common in pigs with respiratory disease.
- Specific pathogens like alpha-hemolytic streptococci, Mycoplasma hyopneumoniae, Pasteurella multocida, Bordetella bronchiseptica, and PRRSV frequently occur together.
- PCV-2 and alpha-hemolytic streptococci are key pathogens in porcine respiratory disease complexes.
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