North American Veterinary Licensing Examination (NAVLE) Practice Test

Which organism, in conjunction with Mycoplasma hyopneumoniae, commonly causes exudative bronchopneumonia in pigs?

1. Bordetella bronchiseptica

2. Fusobacterium necrophorum

3. Hemophilus parasuis

4. Pasteurella multocida

The correct answer is: Pasteurella multocida

The organism that commonly causes exudative bronchopneumonia in pigs, particularly in conjunction with Mycoplasma hyopneumoniae, is Pasteurella multocida. This bacterium is a well-known pathogen in swine and is often involved in secondary bacterial infections that can complicate the respiratory disease initiated by Mycoplasma hyopneumoniae. When pigs are infected with Mycoplasma, their respiratory defense mechanisms may be impaired, making them more susceptible to opportunistic pathogens like Pasteurella multocida. This combination leads to exacerbated respiratory symptoms and more severe disease outcomes. In practice, understanding this interaction is crucial for veterinarians in diagnosing and managing respiratory diseases in pigs. Other organisms listed may also play roles in different conditions affecting swine or have connections to respiratory diseases. However, they do not have the same established association with Mycoplasma hyopneumoniae in causing exudative bronchopneumonia as Pasteurella multocida does. This highlights the specific pathogenic synergy between these two organisms that is particularly notable in clinical cases of pneumonia in pigs.