INTOXICAÇÃO POR MALACHRA FASCIATA JACQ. N.V. EM OVINOS

Abstract

Farmers of the city of Alagoa Grande, Paraíba, Northeastern Brazil claim that a plant known as “quiabo-bravo” cause cutaneous lesions in sheeps. The dermatitis affects mainly the skin slightly pigmented. To prove the toxicity of this plant, the clinical and pathological features of poisoning were studied in 3 sheeps (I, II, III) experientially. Another control sheep (IV) was maintained in a pasture without “quiabo-bravo”. The plant was collected on a farm of city of Alagoa Grande and identified with of the genus Malachra Jacq. N.V. (Malvaceae), specie Malachra fasciata. The plant collected daily, was administered for 21 days as the only food ad libitum.However, the amount ingested was calculated for each of the sheep. Skin lesions of photosensitization appeared on the seventh day of the experiment and became severe until day 21. The mean dose ingested ranged from 129 g/kg to 175 g/kg. The lesions were characterized by alopecia, redness and crusting. In the day 22, the sheepIII was euthanized, and necropsied. Biopsies were performed in the other.No gross or histologic liver lesions were observed in the sheep euthanized. The histopathologic included acantosis, orthokeratosis, and linfoplasmocitic and eosinophilic multifocal infiltrate surroundig blood vessels in the dermis. The Splendore-Hoeppli phenomenon were observed in the dermis of Sheep II, indicating allergic reaction. These experiments indicate that M. fasciata causes primary photosensitization in sheeps.