Abstract
A she-camel of about 6 years of age with neurological signs was admitted to the University Veterinary Teaching Hospital at Qassim, central Saudi Arabia, for diagnosis and treatment. Clinical examination showed lack of coordination of movements, Parkinson's-like tremors of the head and lower lip paralysis. No parasite was detected in the stained blood smear, and except for leukocytosis and monocytosis, the result of the complete blood count (CBC) was normal. The results of the liver and kidney function tests were normal. The animal was infused with 4 units of 5% dextrose saline and injected with vitamin Bl and selenium preparations for the nervous manifestations. However, its health deteriorated rapidly and it was on lateral recumbency by the second day of admission. It died after one more day and was necropsied to investigate the cause of death. Postmortem examination showed slight congestion of the liver and the kidneys. The heart, meninges and the brain were congested and haemorrhagic. Histopathological examination showed acute lymphocytic meningeoencephalomyelitis in the medulla oblongata and spinal cord. Micro-abscesses containing neutrophils were seen in the medulla oblongata. Colonies of Listeria monocytogenes were obtained when the brain tissue was cultured in a cold environment. Smears made from the colonies showed Gram positive cocco-bacilli. Listeria monocytogenes was confirmed by PCR on DNA extracted from brain tissue.