Treponema paraluiscuniculi

Also know as: Rabbit Syphilis — Venereal Spirochaetosis — Treponematosis — Vent Disease

Introduction

Treponematosis, a rabbit venereal disease, is caused by the spirochaete T. cuniculi. It occurs in both sexes and is spread by coitus and from the doe to offspring. The infection is more common in breeding colonies, and is endemic and subclinical in many rabbitries, where it can spread rapidly. It is closely related to the human syphilis organism, but T. cuniculi is not transmissible to other animals or humans.

Clinical Signs

There may be no clinical signs.

Rabbits may present with ulcerated and crusty lesions around the external genitalia, perineal area, nose, eyelids and lips. Lesions on the face are as a result of autoinfection from the rabbit grooming the infected genital area.

Transient infertility may occur in both sexes. In the female this is related to metritis or retained placenta, and in the male this is due to preputial inflammation.

There may also be abortions in the colony.

Diagnosis

Clinical signs are quite suggestive of the disease, although myxomatosis lesions are quite similar. A rapid response to treatment is also a useful sign.

The diagnosis can be made by demonstrating treponemes in dark field microscopic preparations of skin scrapings or of a urine sample. The organism is a motile corkscrew-shaped spirochaete.

Direct immunofluorescence can also be used to demonstrate the organism.

Serological tests, haemagglutination and the indirect immunofluorescent antibody test can be used to detect subclinical carriers.

Treatment

Penicillin is effective in treating this disease. Benzathine penicillin G can be given parenterally two to three times at 7-day intervals.

This should result in regression of the lesions and eliminates the infection.

Potential caecal dysbiosis should be carefully monitored for, and rabbits should be fed a high fibre diet. The antibiotic should not be given orally. Penicillins should not be given to nursing does, even by the parenteral route, for fear of toxic responses in the kits.

In a breeding colony, all rabbits should be treated even if they are not showing any signs. Only seronegative rabbits should be used for breeding to eliminate the infection from the herd.

The prognosis is good and lesions usually heal within 2 weeks. It is possible for the lesions to recede but for a carrier state to remain. Rabbits can also become reinfected if in contact with an infected rabbit.

Treponema paraluiscuniculi Learning Resources
Flashcards Test your knowledge using flashcard type questions	Rabbit Medicine and Surgery Q&A 14

References

Laber-Laird, K. (1996) Handbook of rodent and rabbit medicine Elsevier Health sciences

Harcourt Brown F (2002) Textbook of Rabbit Medicine Butterworth Heinemann Oxford ISBN 0 7506 4002

Rosenthal, K. (2008) Rapid review of exotic animal medicine and husbandry Manson Publishing

Merck and Co (2008) The Merck Veterinary Manual Merial