Filobacterium rodentium ("CAR bacillus")

Test code: B0117 - Ultrasensitive qualitative detection of Filobacterium rodentium bacteria by real time PCR.

Test B0117 is included on the P0063 Rat breeding PCR panel

Cilia-Associated Respiratory Bacillus (“CAR Bacillus”) has been reclassified as Filobacterium rodentium. It is a gram-negative, motile, slightly fusiform, and non-spore-forming bacterium. Infection of rats, mice, rabbits, and some livestock species has been reported. Transmission is primarily through direct contact. There is no evidence for transmission by fomites, vectors, or aerosols. Animals can acquire the infection within one week of birth through their infected mothers. This bacterium is detected more frequently in wild rodent populations, where environmental conditions can facilitate transmission, than in domestic ones.

Good husbandry and exclusion protocols are important to prevent colonies of rodents from becoming infected. There should be no direct contact between infected and uninfected animals. Colony animals should be screened regularly for this bacterium, and all incoming animals should be quarantined and screened for this bacterium.

Animals infected with this bacterium usually develop only subclinical symptoms. However, prolonged infection may lead to respiratory disease, weight loss, ruffled fur, chattering, or snuffing. Infected rats seem to develop more severe symptoms than infected mice. Co-infection with Mycoplasma pulmonis is common.

Culture detection of this bacterium is not very useful because of its fastidious growth requirements. Collecting serum samples for serology testing is not as convenient as collecting fecal or respiratory swab samples for PCR testing. Although this bacterium is primarily present in nasal secretions of infected rodents, infected animals can swallow respiratory secretions that contain CAR bacillus, which can then pass into feces (Compton, 2020). Due to its high sensitivity and specificity, polymerase chain reaction (PCR) can be effectively used for diagnosis on fecal materials collected from rodents (Cundiff et al., 1994).

Utilities:

• Help confirm the disease causing agent
• Shorten the time required to confirm a clinical diagnosis of F. rodentium
• Help ensure that rodent colonies are free of F. rodentium
• Early prevention of spread of F. rodentium within a rodent colony and to other species
• Minimize human exposure to F. rodentium

References:

Compton, S.R. (2020) PCR and RT-PCR in the Diagnosis of Laboratory Animal Infections and in Health Monitoring. J. Am. Assoc. Lab. Anim. Sci. 59:458-468.

Specimen requirements: Fecal pellet, or oral swab, or nasal swab, or tissue.

Contact Zoologix if advice is needed to determine an appropriate specimen type for a specific diagnostic application. For specimen types not listed here, please contact Zoologix to confirm specimen acceptability and shipping instructions.

For all specimen types, if there will be a delay in shipping, or during very warm weather, refrigerate specimens until shipped and ship with a cold pack unless more stringent shipping requirements are specified. Frozen specimens should be shipped so as to remain frozen in transit. See shipping instructions for more information.

Turnaround time: 2 business days

Methodology: Qualitative real time polymerase chain reaction

Normal range: Nondetected