Evaluation of available diagnostic methods for Clostridium piliforme in laboratory rabbits (Oryctolagus cuniculus)

Abstract

Recent literature has indicated that animals seropositive for Clostridium piliforme may have negative findings on polymerase chain reaction (PCR) testing. This study examines and reports on the results of serology, PCR and histopathology tests performed on a group of 20 laboratory rabbits seropositive for C. piliforme using the latest available diagnostic methodologies. The presence of the organism was not confirmed by either PCR or histopathology in this group of 20 for C. piliforme seropositive rabbits. This presents challenges for laboratory animal veterinarians and scientists wishing to establish the presence of the organism with commonly available diagnostic methods and means that clinical signs of disease in addition to diagnostic results must be interpreted together.

Biology and Diseases of Rabbits

“…Etiology C. piliforme is a pleomorphic, Gramnegative, spore-forming, motile, obligate intracellular rod-shaped bacterium that causes Tyzzer's disease and infects various animals including mice, nonhuman primates, gerbils, rats, rabbits, and others (Allen et al, 1965;Ganaway et al, 1971;Pritt et al, 2010). Infection has also been reported in a human patient with human immunodeficiency virus-1 (Smith et al, 1996).…”

“…The dams of affected litters occasionally died after a diarrheal disease that was more protracted than that of the offspring (Allen et al, 1965). C. piliforme infection may also be subclinical and transient as immunocompetent hosts may clear the infection (Ganaway et al, 1971;Pritt et al, 2010). C. piliforme infection may also be subclinical and transient as immunocompetent hosts may clear the infection (Ganaway et al, 1971;Pritt et al, 2010).…”

“…Contact with soiled bedding or diseased rabbits have been used experimentally to transmit the disease to other rabbits (Allen et al, 1965). It is possible that subclinically infected rabbits (carriers) may introduce the organism into a colony (Allen et al, 1965;Pritt et al, 2010). In mice, increased susceptibility to infection has been associated with stress (Allen et al, 1965).…”

“…In mice, increased susceptibility to infection has been associated with stress (Allen et al, 1965). Furthermore, treatment with cyclophosphamide, cortisone, and prednisolone has been used experimentally to reproduce the disease in animals, suggesting that immunosuppression plays a role in pathogenesis (Allen et al, 1965;Cutlip et al, 1971;Pritt et al, 2010). Animals stressed by poor environmental conditions including overcrowding and extreme temperatures can develop the disease (Cutlip et al, 1971;Wobeser et al, 2009).…”

Biology and Diseases of Rats

“…Histopathologic evaluation is diagnostic if the characteristic bacilli are observed (Tyzzer, 1917;Duncan et al, 1993). Serologic screening is rapid and technically simple (Motzel and Riley, 1992) but is subject to false positives, yielding results that can be difficult to put into context, as has been recently reported in rabbits (Pritt et al, 2010). Bacilli are intracellular, are often numerous, and may appear as either a jumbled array (pickup stick) or parallel arrangement, as dictated by the shape of the cell.…”