Status Spongiosis, Optic Neuropathy, and Retinal Degeneration in Helichrysum argyrosphaerum Poisoning in Sheep and a Goat

摘要: Lesions of natural Helichrysum argyrosphaerum poisoning were studied in eight sheep and one goat. Light microscopic examination revealed widespread, bilaterally symmetrical status spongiosis the white matter brain consistently present subependymal area adjacent to lateral ventricles, cerebellar peduncles, stem all animals. In three animals, ultrastructural finding intramyelinic vacuolation due splitting myelin lamellae at intraperiod lines indicated edema. There was also mild distension perivascular extracellular spaces severely affected areas. Significant changes absent neurons, glial cells, axons, or blood vessel walls. Myelin edema associated with degeneration loss axons astrocytic gliosis intraorbital intracranial portions optic nerves. intracanalicular nerves animals that studied, more chronic lesions consisting fibrosis atrophy nerve suggested neuropathy follows compression canal as a result The toxic principle plant caused degenerative retinopathy five essential histopathologic change photoreceptor outer segments predominantly nontapetal retina. These retinal hyperplasia hypertrophy migration pigmented epithelium, focal separation, depletion nuclear layers.