Intoxicação experimental em ovinos por Mascagnia rígida (A Juss) Griseb. (Malpighiaceae): estudos fitoquímico, fitoanatômico e aspectos clínicos, laboratoriais e ecocardiográficos

Abstract

The objectives of this research were to identify chemicals groups of toxicological relevance in M. rigida, to study the microscopic characteristics of its leaves and stem, to verify if sheep is susceptible to intraruminal administration of M. rigida and to assess the clinical, electrocardiographic, echocardiographic and clinicopathological effects. Fifteen male Santa Inês sheep, divided in three groups, were used: G1 treated with water; G2 treated with M. rigida (20 g/kg/day) for three days; G3 treated with M. rigida (20 g/kg/day) for seven days. All treatments were administered by an orogastric tube. Polyphenols, tannins, flavonoids, saponins and quaternary alkaloids were detected on the phytochemical analyses. The following anatomical characteristics were identified in M. rigida leaves: polygonal adaxial cells, sinuous abaxial cells, anomocitic stomata; mesophyll built as single layer of elongated adaxial cells, palisade parenchyma in single layer, lacunous stratified parenchyma; central vein containing crystals, and arch shaped vascular system. The characteristics of M. rigida stem were: small and square shaped epidermic cells; thickened collenchyme cells, and stratified parenchyma; lignified secondary phloem, radial xylem. M. rigida produced clinical signs such as depression, exercise intolerance, and pollakyuria. One sheep had sudden death during exercise. M. rigida administration produced an increase in heart rate , a decrease in fractional ejection, and fractional shortening. No electrocardiographic or clinicopathological changes were detected.