Читать книгу Large Animal Neurology - Joe Mayhew - Страница 92

Penetration of the CNS by fly larvae (myiasis) and roundworms (nematodiasis) is usually accidental and random, whereas invasion by some nematodes and tapeworm cysts (coenurosis) is part of the respective life cycles. In the natural host, minimal damage may result. In unnatural hosts, however, massive tissue destruction, hemorrhage, protein exudate, and an influx of neutrophils and macrophages with variable numbers of eosinophils and giant cells occur. Such parasites can arrive in the CNS through natural foramina or via the blood supply. Subsequent meanderings can be tortuous and surprisingly may simply separate the tissues without causing much inflammation. Also, parasites can leave the CNS after creating devastation.