Lethal cerebrospinal elaphostrongylosis in a reindeer calf.

Lethal elaphostrongylosis in a reindeer calf is described. The calf showed signs of abnormal behaviour, mental confusion and reduced vision due to lesions in the brain parenchyma caused by migrating mature Elaphostrongylus rangiferi. Traumatically caused malacia and secondary axon degeneration were observed in all brain areas. Nematodes were found in the skeletal muscles, epidural space of the spinal cord, and in the subdural spaces and leptomeninges of the cord and brain. Developing nematode ova were sectioned along migratory tracks in the brain, in the subdural space of the cord, epidural adipose tissue, perineurium of the spinal nerve roots and in the lungs.