Illustrative guide of clinical signs of rabbits with E. cuniculi
Esther van Praag, Ph.D.
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The protozoal parasite Encephalitozoon cuniculi lives in the nervous system and major organs of rabbits. A variety of clinical signs characterize the disease, yet they vary from one rabbit to another, rendering diagnosis of the disease difficult.
Damage is observed on organs, causing liver failure and kidney failure and calcification. These changes affect the biochemical parameters and can be measured during a complete blood test.
The behavior and general appearance of a rabbit can be affected. Main signs that are characteristic for an E. cuniculi infection are illustrated here. Limb weakness and pressure on the inner ear can lead to a loss of balance and hopping in circles.
In the end phase, seizure attack become usually more frequent and stronger, and the rabbit can become comatose and die.
More or less pronounced torticollis (commonly called head tilt or wry neck)
Hind limb weakness and paralysis
Paralysis of the hindlimbs
Phacoclastic uveitis, cataracts, nystagmus
Neurological signs such as seizure with convulsions, shuddering
Thanks are due to Dr. Magdalena Stasiowska (Przychodnia Weterynaryjna – Wrocław, Poland), to Michel Gruaz, (Switzerland) and to Emma Staub (USA). Many thanks also to Renee Brennan for sharing the video of her head-tilted rabbit Rudy.
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