Controle da intoxicação por Ipomoea carnea subsp. fistulosa em caprinos.

Abstract

In Brazil, plants containing swainsonine constitute a very important group of toxic plants, including Ipomoea carnea subsp. fistulosa, Ipomoea riedelii, Ipomoea sericophyla, Ipomoea verbascoidea, Turbina cordata and Sida carpinifolia, which cause nervous signs, especially in goats, but also in cattle, horses and sheep. The control of these poisonings involves the withdrawn of the animal from where the plant occurs or the elimination of the plant from the areas invaded. This thesis describes the use of the technique of conditioned food aversion to control the poisoning by /. carnea. To test this technique as a method of control, three experiments were carried out by administering lithium chloride (LiCl) at a dose of 175-200 mg / kg after ingestion of the plant to goats. In the first experiment 10 goats that had the habit to ingest the plant and showed clinical signs of intoxication were averted. Despite various aversive treatments the animals returned to ingest I. carnea, demonstrating that the technique is not efficient in goats that are already accustomed to consume the plant. In the second experiment, 14 naive goats were adapted to ingest the plant in the pasture and then averted. In this group the aversion persisted until the end of the experiment, two years and eight months after aversion. In another experiment, 20 goats were adapted to consume I. carnea, and then averted with LiCl. The averted goats were transferred to Marajo Island and visits were performed to the island over a two year period at 2-3 month intervals to determine if the goats still averted. Additionally, a survey was made to see the occurrence of the poisoning in neighboring farms that raised goats. After two years of observation the goats averted did not ingest the plant in the pasture, while in six neighboring farms the disease was observed with a prevalence of up to 60%. These results demonstrated the efficacy of conditioned food aversion to avoid ingestion of /. carnea in goats recently adapted to ingest the plant. They also demonstrated that the technique can be used with success in the conditions of the Maraj6 Island to avoid this plant poisoning.