Clinical and pathological effects of Calotropis procera exposure in sheep and rats.

This study aimed to describe the toxic effects resulting from the administration of Calotropis procera (Aiton) W. T. Aiton latex to rats and C. procera leaves to sheep. We studied male sheep that received C. procera leaves by gavage. Twenty male rats were separated into 5 groups and were subjected to an intra-peritoneal injection of fresh C. procera latex (without carrier solvent) at 1.0, 0.6, 0.3 or 0.1 ml of latex/kg of body weight, and control animals were injected with 0.9% NaCl. All rats were treated with the highest dose, but none of the rats from the other groups, died. The histological lesions were restricted to rats dosed with 1.0 ml of latex/kg body weight and included multi-focal coagulation necrosis of cardiac fibers and vacuolized hepatocytes. Subsequently, three groups of two sheep were treated with (1) a single dose of 30 g/kg, (2) a single dose of 60 g/kg or (3) 60 g/kg per day for 10 consecutive days. Exposure to the C. procera leaves was responsible for tachycardia and transitory cardiac arrhythmias in sheep from all groups. Gross pathological analysis of sheep dosed with 60 g/kg per day for 10 days revealed mild ascites, exudates on the trachea, pulmonary edema, mild hemorrhage in the liver, hydropericardium, flaccid heart, ulcers on the abomasum and kidneys presenting pale juxtamedullary cortex. The histological findings of the rat and sheep studies were similar and included multi-focal coagulation necrosis of cardiac fibers and vacuolized hepatocytes. In conclusion, our findings indicate that C. procera is a cardiotoxic and hepatotoxic plant.

Avaliação da atividade moluscicida do látex de três espécies de Euphorbia (Euphorbiaceae) sobre Leptinaria unilamellata d'Orbigny, 1835 (Gastropoda - Subulinidae) / Assessment of moluscicidal activity of the latex of three Euphorbia (Euphorbiaceae) species on Leptinaria unilamellata d'Obigny 1835 (Gastropoda - Subulinidae)

Gastrópodes pulmonados terrestres podem atuar como hospedeiros intermediários de helmintos. Os primeiros registros do controle químico desses invertebrados datam do início do século XX e as substâncias utilizadas eram toxinas inespecíficas já empregadas no controle de outras pragas. Moluscicidas sintéticos apresentam limitações técnicas que estimularam a busca de substitutos naturais. Dentre as várias espécies vegetais com atividade moluscicida, Euphorbia cotinifolia L., Euphorbia milii des Moul. var. splendens (Bojer ex Hook) Ursch & Leandri e Euphorbia tirucalli L. despertam atenção pelos excelentes resultados obtidos sobre moluscos aquáticos. Contudo, estudos sobre a atividade de plantas moluscicidas em moluscos terrestres são pouco comuns, apesar de sua grande importância parasitológica e agrícola. As semelhanças anatomo-fisiológicas entre espécies de moluscos aquáticos e terrestres sugerem que estratégias de controle químico possam ter eficiência semelhante para os dois grupos de invertebrados. Com base nessa hipótese, o presente trabalho teve como objetivo avaliar a atividade moluscicida do látex de três espécies do gênero Euphorbia sobre Leptinaria unilamellata d'Orbigny, 1835, gastrópode terrestre descrito como hospedeiro intermediário de helmintos trematódeos digenéticos que parasitam animais domésticos. Destas E. milii var. splendens apresentou efeito moluscicida elevado sobre L. unilamellata, 100 por cento até uma diluição de 1:800, já nos primeiros minutos após a aplicação. Embora citadas na literatura como tóxicas para moluscos aquáticos, E. cotinifolia e E. tirucalli não exibiram atividade moluscicida sobre L. unilamellata. Os resultados do presente estudo indicam que o látex de E. milii var. splendens pode se constituir em uma estratégia viável de controle químico de moluscos terrestres.

Pulmonate terrestrial gastropods can be intermediate hosts for helminthes. The first records of chemically controlling these invertebrates date back to the beginning of the 20th century. The substances used were unspecific toxins which were already used for controlling other pests. Synthetic molluscicides have technical limitations that stimulated a search for natural substitutes. Among the many vegetal species that have molluscicidal activity, Euphorbia cotinifolia L., Euphorbia milii des Moul. var. splendens (Bojer ex Hook) Ursch & Leandri and Euphorbia tirucalli L. call attention because of the excellent results that have been obtained when they are used on aquatic mollusks. However, studies on the activity of molluscicidal plants on terrestrial mollusks are rare, in spite of its great importance in controlling parasites and to agriculture. Anatomical and physiological similarities among species of aquatic and terrestrial mollusks suggest that chemical control strategies can be effective on both groups of invertebrates. Based on this hypothesis, we assessed the molluscicidal activity of the latex of three species of the genus Euphorbia on the terrestrial gastropod Leptinaria unilamellata d'Orbigny, 1835, described as an intermediate host of digenetic trematode helminths that parasitize domestic animals. E. milii var. splendens had the highest molluscicidal effect on L. unilamellata, being 100 percent lethal in concentrations up to 1:1800 in the first minutes after application. Although E. cotinifolia and E. tirucalli have been cited in the literature as toxic to aquatic mollusks, they did not have molluscicidal activity on L. unilamellata. The results of our study indicate that the latex of E. milii var. splendens may be a viable strategy for the chemical control of terrestrial mollusks.