Intoxicação experimental por Ipomoea verbascoidea em caprinos

Abstract

The number of cases of animals poisoned by plants is increasing every year and further studies are underway to assess the damage caused by them. Plants containing swainsonine toxic principle cause neurological damage. Damage caused to the reproductive and visual systems has not been described. The objective of this work is to demonstrate by experiment the changes caused by Ipomoea verbascoidea poisoning in the male reproductive system, in the retina and optic nerve in goats. To produce the experimental condition, dried leaves of I. verbascoidea containing 0.02% swainsonine were supplied at a dose of 4g/kg (swainsonine 0.8 mg / kg) in three groups of three animals. The goats in Group I received daily doses of the plant for 45 days and were euthanized on day 46 of the experiment. The goats from Group II received daily doses of the plant for 55 days and were euthanized on day 120 of the experiment. Group III was the control group. The first change, a decrease in semen parameters, was observed on the 14th day of the experiment. On the 20th day, neurological symptoms such as slowness, drowsiness, negative flehmen response and lack of libido were observed in goats 1, 3, 4 and 5. These animals presented decreased scrotal circumference after 35 days from the beginning of the experiment. Between days 35 and 37, all goats showed typical symptoms of LSD, especially motor coordination, ataxia, dysmetria, resulting in impotentia coeundi. In evaluating the serum concentrations of testosterone, there was significant difference between the control group and the groups of poisoned animals. .The main histopathological findings in the reproductive system were observed in the seminiferous epithelium. These were cytoplasmic, vacuolization in Sertoli and germinal cells, a decrease in the Leydig cells, interstitial edema and ogliospermia. There was a reduction of the germinal epithelium, accumulation of proteinacea material in the lumen of the seminiferous tubules and atrophy or absence of stereocilios of the epithelial cells of the epididymis. Alterations of the ocular globe were vacuolization of the retinal ganglion cells, a number of degenerated neurons, and others with intracytoplasmic accumulation of liquid with basophilic characteristics. There was reduced thickness of the optic nerve. The nerve fiber layer close to the optic disc presented an edema and mononuclear inflammatory cell infiltrate. It is concluded that I. verbascoidea poisoning causes testicular degeneration and optic neuritis.