Etiology: Bordetella bronchiseptica is a small, motile Gram-negative, urease-producing bacillus. Bordetella infects multiple species and all isolates produce virulence factors.
Incidence: Incidence of disease is uncommon in laboratory guinea pigs.
Transmission: The organism can be carried by rats, rabbits, dogs, cats, swine, and primates. “Strains” are specific for certain animal hosts. Transmission between animals occurs by direct contact or aerosol. A carrier state exists in the guinea pig. Incubation periods in new infections range from five to seven days.
Clinical Signs: Carrier or subclinically infected animals may have no signs. Acutely infected animals may exhibit sneezing, nasal discharge, anorexia, weight loss, conjunctivitis (A.), torticollis, dyspnea, and death. Stillbirths and abortions may occur in pregnant females. Young animals are more severely affected.
Pathology: Lesions include mucopurulent rhinitis, tracheitis, and pulmonary consolidation with a purulent bronchitis and bronchopneumonia (B.). Exudate can be present in the tympanic bullae.
Diagnosis: Culture of exudates and bacterial identification provides diagnostic confirmation of the disease. Gram staining impression smears during post-mortem exam can provide a tentative diagnosis, since Bordetella is the primary Gram-negative bacillus to cause respiratory disease in guinea pigs. PCR can also be used.