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It is well known that several of the swainsonine-containing plant species found widespread around the world have a negative economic impact in each country. In Argentina, most of the information on the poisonous plant species that produce α-mannosidosis is published in Spanish and thus not available to most English speaking researchers interested in toxic plants. Therefore, the aim of this review is to summarize the information about swainsonine-containing plants in Argentina, which are extensively distributed throughout different ecoregions of the country. To date, five species from three genera have been shown to induce α-mannosidosis in livestock in Argentina: Ipomoea carnea subsp. fi stulosa, Ipomoea hieronymi subsp. calchaquina (Convolvulaceae), Astragalus garbancillo, Astragalus pehuenches (Fabaceae), and Sida rodrigoi (Malvaceae). These species contain the indolizidine alkaloid swainsonine, which inhibits the lysosomal enzyme α-mannosidase and consequently affects glycoprotein metabolism, resulting in partially metabolized sugars. The prolonged consumption of these poisonous plants produces progressive weight loss and clinical signs related to a nervous disorder, characterized by tremors of head and neck, abnormalities of gait, difficulty in standing, ataxia and wide-based stance. Histological lesions are mainly characterized by vacuolation of different cells, especially neurons of the central nervous system. The main animal model used to study α-mannosidosis is the guinea pig because, when experimentally poisoned, it exhibits many of the characteristics of naturally intoxicated livestock. Estación Experimental Agropecuaria Bariloche Fil: Cholich, Luciana Andrea. Universidad Nacional del Nordeste. Facultad de Ciencias Veterinarias; Argentina Fil: Cholich, Luciana Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Martinez, Agustin. Instituto Nacional de Tecnologia Agropecuaria (INTA). Estacion Experimental Agropecuaria Bariloche. Grupo de Sanidad Animal; Argentina Fil: Micheloud, Juan Francisco. Universidad Católica de Salta. Facultad de Ciencias Veterinarias y Agronomía; Argentina Fil: Micheloud, Juan Francisco. Instituto Nacional de Tecnologia Agropecuaria (INTA). Instituto de Investigación Animal del Chaco Semiárido. Área de Sanidad Animal; Argentina Fil: Pistán, Maria Elena. Universidad Nacional del Nordeste. Facultad de Ciencias Veterinarias; Argentina Fil: Garcia, Enrique Nicolas. Universidad Nacional del Nordeste. Facultad de Ciencias Veterinarias; Argentina Fil: Robles, Carlos Alejandro. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bariloche. Grupo de Sanidad Animal; Argentina Fil: Ortega, Hugo Hector. Universidad Nacional del Litoral. Instituto de Ciencias Veterinarias del Litoral; Argentina Fil: Ortega, Hugo Hector. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Gimeno, Eduardo Juan. Universidad Nacional de la Plata. Facultad de Ciencias Veterinarias; Argentina Fil: Gimeno, Eduardo Juan. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

The aim of this paper was to present the first report of Prosopis nigra poisoning of cattle in Argentina. Outbreaks occurred in five farms located in Salta and Santiago del Estero provinces. All animals were examined, euthanized and necropsied. Clinical signs included tongue protrusion, twitches and tremors of muscles of mastication, weight loss and lethargy. Severe atrophy of the masseter, buccinator and lingual muscles was observed, along with neuronal vacuolation in the nuclei of the trigeminal, facial, and hypoglossus nerves. These findings and the clinical signs are consistent with results obtained in animals, spontaneously and experimentally intoxicated with Prosopis juliflora in previous studies. Several species of this genus are native to Argentina. Farmers should be warned about the suspected toxicity by Prosopis nigra, since this species has wide geographical distribution in the country.

Introduction: Prosopis spp. pods have shown to be a potential source of protein and energy in livestock. However, prolonged ingestion of some of these species produces neurological symptoms in ruminants. Objective: In the present study, the alkaloid content and the in vitro neurotoxic activity of alkaloid enriched-extracts from P. flexuosa and P. nigra pods were determined in order to elucidate the mechanism of animal poisoning caused by these species. Methods: The main alkaloids present in both extracts were analysed by high performance liquid chromatography-high resolution mass spectrometry (HPLC-HRMS). The cytotoxic activity of Prosopis alkaloid enriched-extracts in primary mixed glial cell culture was assessed by phase contrast microscopy and using neutral red, and lactate dehydrogenase (LDH) activity assays. Results: Juliprosine and juliprosopine were identified in P. flexuosa pods, while the absence of these alkaloids in P. nigra was confirmed. Both extracts (5-30 μg/mL) induced in a dose dependent manner, morphological alterations, such as swelling, enlargement and detachment from the culture surface. Consistent with this, decrease in cell viability and release of LDH 48 hours after exposure, revealed that P. flexuosa pods was significantly more cytotoxic than P. nigra. Conclusions: In P. flexuosa pods, juliprosine and juliprosopine alkaloids were identified for the first time. Moreover, the present study suggests that the cytotoxic effect displayed by both extracts is due to its alkaloid content. However, the presence of piperidine alkaloids in P. flexuosa could explain the greater cytotoxicity on glial cells with respect to P. nigra that was not shown to contain these alkaloids. Resumen Introducción: Las vainas de diversas especies de Prosopis muestran ser una potencial fuente de proteínas y energía para el ganado. Sin embargo, la ingestión prolongada de algunas de estas especies produce síntomas neurológicos en los rumiantes. Objetivo: En el presente estudio se determinó el contenido de alcaloides y la actividad neurotóxica in vitro de los extractos enriquecidos con alcaloides obtenidos en las vainas de P. flexuosa y P. nigra, con el fin de dilucidar el mecanismo de la intoxicación animal causada por estas especies. Métodos: Los principales alcaloides presentes en ambos extractos se analizaron mediante cromatografía líquida de alto rendimiento-espectrometría de masas de alta resolución (HPLC-HRMS). La actividad citotóxica de los extractos enriquecidos con alcaloides de Prosopis se determinó en cultivos primarios de células gliales mixtas y se evaluó mediante microscopía de contraste de fase y utilizando ensayos de actividad de rojo neutro y de deshidrogenasa láctica (LDH). Resultados: Se identificaron la juliprosina y la juliprosopina en las vainas de P. flexuosa, mientras que se confirmó la ausencia de estos alcaloides piperidínicos en P. nigra. Ambos extractos (5-30 μg/mL) indujeron, de manera dependiente a la dosis, alteraciones morfológicas, como hinchazón, agrandamiento y desprendimiento de la superficie de cultivo. En consecuencia, la disminución de la viabilidad celular y la liberación de la LDH después de 48 horas de exposición, reveló que las vainas de P. flexuosa eran significativamente más citotóxicas que las de P. nigra. Conclusiones: El presente estudio muestra la presencia de los alcaloides juliprosina y juliprosopina en vainas de P. flexuosa y sugiere que el efecto citotóxico mostrado por ambos extractos se debe al contenido de alcaloides. Sin embargo, la presencia de estos alcaloides piperidínicos en P. flexuosa podría explicar la mayor citotoxicidad en las células gliales con respecto a P. nigra que no mostró que tuviera estos alcaloides.

Senna occidentalis may be accidently ingested by humans and animals. In this study, the percentages of S. occidentalis seeds necessary for experimental reproduction of hepatic encephalopathy were determined in a pig model and the biochemical and microscopic pathology is described in detail, with emphasis on the astrocytes. The experimental groups (G1, G2 and G3) were fed rations containing 5%, 7.5% and 10% of S. occidentalis seeds for 7–11 days. Pigs from the three experimental groups showed incoordination, ataxia, disorientation, head pressing, anorexia, recumbency and depression. In addition, the enzymes aspartate aminotransferase, alkaline phosphatase and creatine phosphokinase increased in all treated animals, which also showed higher serum total bilirubin and ammonia levels than in the control group (C). Microscopically, all experimental animals revealed acute hepatocellular swelling, multifocal coagulative necrosis in the pancreas, necrosis in the cardiac muscle, severe spongiosis in brain white and grey matter, and Alzheimer type II astrocytes in grey matter of the cerebral cortex. These cells were glial fibrillary acidic protein (GFAP) negative in G3. In white matter, a decrease in the positive area occupied by GFAP-immunolabelling and in the number of astrocytes per immunoreactive area was observed in G3 animals (5.35 ± 1.14% and 410 ± 45 cells/mm2, respectively) compared to the C animals (13.93 ± 1.59% and 581 ± 36 cells/mm2, respectively). This loss of GFAP was accompanied by alterations in astrocyte morphology, such as shrinkage of the cell body and retraction of the extending processes. This pig model of ammonia-mediated astrocyte damage could be used to study not only poisoning by S. occidentalis, but also other medical conditions resulting in hepatoencephalopathy.

The prolonged consumption of Ipomoea carnea produces neurologic symptoms in animals and a typical histological lesion, cytoplasmic vacuolization, especially in neurons. The toxic principles of I. carnea are the alkaloids swainsonine and calystegines B1, B2, B3 and C1. In this study, primary brain cultures from newborn mouse containing mixed glial cells were utilized. These cells were exposed to Ipomoea extracts containing between 0 and 250 μM swainsonine for 48 h. Morphological changes were investigated through Phase Contrast microscopy and Rosenfeld's staining. The extract induced cytoplasmic vacuolization in astrocytes and microglia in a dose dependent manner, being more evident when cultures were exposed to 250 μM of swainsonine. In addition, acridine orange staining evidenced an increase in the number of lysosomes in both microglia and astrocytes cells. Consistent with this, scanning electron microscopy also showed that both types of cells presented morphological characteristics of cell activation. Ultrastructurally, cells showed vacuoles filled with amorphous material and surrounded by a single membrane and also multilayer membranes. Taken together, these findings suggest that swainsonine along with calystegines, are probably responsible for the activation of glial cells due to a possible lysosomal dysfunction and therefore intracellular storage. Our results demonstrate that this in vitro glial cell model is a very good alternative to in vivo studies that require several weeks of animal intoxication to observe similar neurotoxic effects.

Se describen los hallazgos clínicos y patológicos del envenenamiento experimental por Senna occidentalis en cerdos. Seis cerdos se distribuyeron en dos grupos, uno de los cuales se alimentó con una ración que contenía 10% de vainas y semillas de S. occidentalis por 30 días y el otro grupo permaneció como grupo control. Los animales intoxicados mostraron letargia, ataxia, temblores musculares, emaciación y recumbencia. La enzima creatina fosfoquinasa aumentó significativamente en los cerdos intoxicados con S. occidentalis (p, The clinical and pathological findings of the experimental poisoning by Senna occidentalis in pigs are described. Six pigs were distributed into two groups, one of which was fed a ration containing 10% pods and seeds of S. occidentalis for 30 days and the other group remained as a control group. The intoxicated animals showed lethargy, ataxia, muscular tremors, emaciation and recumbency. The enzyme creatine phosphokinase increased significantly in pigs intoxicated with S. occidentalis (p

This study describes an occurrence of pink morning glory (Ipomoea carnea) intoxication in goats in northern Argentina. The clinical signs displayed by the affected animals were ataxia, lethargy, emaciation, hypertonia of the neck muscles, spastic paresis in the hind legs, abnormal postural reactions and death. The clinico-pathologic examination revealed that the affected animals were anemic and their serum level of aspartate aminotransferase was significantly increased. Cytoplasmic vacuolation in the Purkinje cells and pancreatic acinar cells was observed by histological examination. The neuronal lectin binding pattern showed a strong positive reaction to WGA (Triticum vulgaris), sWGA (succinylated T. vulgaris) and LCA (Lens culinaris). Although I. carnea is common in tropical regions, this is the first report of spontaneous poisoning in goats in Argentina.

Ipomoea carnea subsp. fistulosa, aguapei or mandiyura, is responsible for lysosomal storage in goats. The shrub contains several alkaloids, mainly swansonine which inhibits lysosomal α-mannosidase and Golgi mannosidase II. Poisoning occurs by inhibition of these hydrolases. There is neuronal vacuolation, endocrine dysfunction, cardiovascular and gastrointestinal injury, and immune disorders. Clinical signs and pathology of the experimental poisoning of goats by Ipomoea carnea in Argentina are here described. Five goats received fresh leaves and stems of Ipomoea. At the beginning, the goats did not consume the plant, but later, it was preferred over any other forage. High dose induced rapid intoxication, whereas with low doses, the course of the toxicosis was more protracted. The goats were euthanized when they were recumbent. Cerebrum, cerebellum, medulla oblongata, pons and colliculi, were routinely processed for histology. In nine days, the following clinical signs developed: abnormal fascies, dilated nostrils and abnormal postures of the head, cephalic tremors and nystagmus, difficulty in standing. Subsequently, the goats had a tendency to fall, always to the left, with spastic convulsions. There was lack in coordination of voluntary movements due to Purkinje and deep nuclei neurons damage. The cochlear reflex originated hyperreflexia, abnormal posture, head movements and tremors. The withdrawal reflex produced flexor muscles hypersensitivity at the four legs, later depression and stupor. Abnormal responses to sounds were related to collicular lesions. Thalamic damage altered the withdrawal reflex, showing incomplete reaction. The observed cervical hair bristling was attributed to a thalamic regulated nociceptive response. Depression may be associated with agonists of lysergic acid contained in Ipomoea. These clinical signs were correlated with lesions in different parts of the CNS., Facultad de Ciencias Veterinarias

Ipomoea carnea subsp. fistulosa (Convolvulaceae) causes poisoning of goats, sheep and cattle in many tropical and subtropical countries. The pathophysiology of this poisoning mainly involves an abnormal glycoprotein metabolism. The aim of this study was to describe the potential toxicity of I. carnea in a guinea pig model through its effect on hematopoiesis in a time course study of 40 days. Experimental poisoning was achieved by feeding animals with "small balls" prepared with milled leaves of I. carnea mixed with commercial crushed pellets for rodents. Hematologic and biochemical parameters, bone marrow and spleencellularities, histopathologic evaluations and lectin-histochemistrywere performed during the scheduled time of the study. The treatment with "small balls" caused significant changes in the weight of spleen, a notable decrease in peripheral red blood cells, and concomitantwith morphological and histopathologicalalterationsin hematopoietic tissues. Overall, the present study suggested that 20 days ofthis treatmentcouldbe enough to develop bone marrow hypoplasia and vacuolation of white cells of spleen, blood and lymph nodes with a transient erythropoietic contribution of the splenic niche. Moreover, this work provides a cheap and simple method for detecting preclinical cases of intoxication by I. carnea in livestock. Fil: García, Enrique N.. Universidad Nacional del Nordeste. Facultad de Ciencias Veterinarias; Argentina Fil: Aguirre, María V.. Universidad Nacional del Nordeste. Facultad de Medicina; Argentina Fil: Gimeno, Eduardo Juan. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Rios, Elvio E.. Universidad Nacional del Nordeste. Facultad de Ciencias Veterinarias; Argentina Fil: Acosta, Ofelia Cristina. Universidad Nacional del Nordeste. Facultad de Ciencias Veterinarias; Argentina Fil: Cholich, Luciana Andrea. Universidad Nacional del Nordeste. Facultad de Ciencias Veterinarias; Argentina

Ipomoea carnea is a toxic plant that affects goats, with symptoms being characterised by nervous disorders and death. Swainsonine and calystegines are the principal toxic components isolated from I. carnea, which also yields lysergic acid derivatives. The aim of this study was to improve the clinical characterisation of experimental intoxication by I. carnea in guinea pigs through the evaluation of behavioural changes and to perform a thorough histopathological analysis of the affected CNS. Leaves of I. carnea were administered to guinea pigs. Open-field gait analysis and monoamine levels were measured. The poisoned animals exhibited increased vocalisation, lethargy, and a reduction in the locomotion frequency after the fourth week of intoxication, as demonstrated in the open-field test. Significant differences were observed in hind-limb gait width by the last week of intoxication. After 65 days, the guinea pigs were euthanised, necropsied, and examined using light and electron microscopy. At the end of the experiment, plasma serotonin decreased. In contrast, dopamine decreased, and noradrenaline increased in urine. Brain sections were evaluated with conventional histological methods and immunohistochemistry (IHC), as well as by transmission electron microscopy (TEM). Vacuoles were observed throughout the brain, but they were particularly prominent in the brainstem. In addition, there were PAS-negative regions, and the Nissl substance was dispersed or absent, which was confirmed with the Kluver-Barreda stain. Moderate microgliosis was observed by immunohistochemistry. In the medulla oblongata, numerous ubiquitin-positive spheroids together with neuronal degeneration were observed in the nucleus gracilis/cuneatus. Furthermore, vacuoles were observed in astrocytes, oligodendrocytes, and endothelial cells by TEM. Our results showed that the behavioural effects may have been caused by alterations in the brain in conjunction with changes in monoamine levels. This research confirms the utility of this model for studying the pathogenesis of plant-induced lysosomal storage diseases. Fil: Cholich, Luciana Andrea. Universidad Nacional del Nordeste. Facultad de Cs.veterinarias. Departamento de Clinica. Cátedra de Farmacología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Marquez, Mercedes. Universidad Autonoma de Barcelona. Facultad de Veterinaria; España Fil: Pumarola i Batlle, Martí. Universidad Autonoma de Barcelona. Facultad de Veterinaria; España Fil: Gimeno, Eduardo Juan. Universidad Nacional de La Plata; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Teibler, Gladys Pamela. Universidad Nacional del Nordeste. Facultad de Cs.veterinarias. Departamento de Clinica. Cátedra de Farmacología; Argentina Fil: Rios, Elvio E.. Universidad Nacional del Nordeste. Facultad de Ciencias Veterinarias; Argentina Fil: Acosta, Ofelia Cristina. Universidad Nacional del Nordeste. Facultad de Cs.veterinarias. Departamento de Clinica. Cátedra de Farmacología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Ipomoea carneaes una planta tóxica debido a los alcaloides swainsonina y calisteginas, que provoca pérdidaseconómicas en la producción animal del nordeste argentino. El propósito de este estudio fuedescribir las lesiones microscópicas verificadas en páncreas y riñón, así como los cambios delperfil bioquímico renal causados por la intoxicación experimental con I. carnea en caprinos.Se emplearon 9 cabras alimentadas con alfalfa; 4 de ellas obraron como testigos y las 5 restantesfueron sometidas a la ingestión de hojas de I. carnea a razón de 50 g/kg/día durante 53 días,fecha en que fueron sacrificadas debido al grave deterioro de su salud. Semanalmente se realizaronexámenes clínicos y extracciones de sangre y orina. Urea y creatinina incrementaronprogresivamente su concentración sérica en los animales intoxicados, quienes también revelaronanormalidades en el urianálisis. Los órganos más afectados fueron páncreas y riñón. Ademásde la vacuolización citoplasmática descripta por otros autores, en el presente estudio seconstató la presencia de contenido eosinofilico intratubular y ensanchamiento del espacio deBowman en los riñones, daños que explicarían las anormalidades detectadas en orina y sangre.Tales cambios asumen utilidad al momento de realizar el diagnóstico de esta intoxicación. Ipomoea carnea is a toxic plant due to the alkaloids swainsonine and calystegines, which causes animal production economic losses in Northeast Argentina. The purpose of this study was to describe microscopic lesions verified in pancreas and kidney, as well as renal biochemical profile changes caused by I. carnea experimental intoxication in goats. Nine goats fed on alfalfa hay were used; four of them were controls and the five remainder were submitted to the ingestion of I. carnea leaves (50 g/kg/day during 53 days). At this time these animals were sacrificed due to its serious health deterioration. Clinical exams, as well as blood and urine sampling, were weekly carried out. Urea and creatinine progressively increased their serum concentration in the intoxicated animals, which also revealed abnormalities in the urine composition. Pancreas and kidneys were gravely affected. Besides the intracellular vacuolization already described by other authors, the presence of an intratubular eosinophillic content, as well as an expansion of Bowman space in the kidneys, were verified in present study. These damages would explain the abnormalities detected in urine and blood. Such changes are useful to optimize the diagnosis of this intoxication Fil: Rios, E.. Universidad Nacional del Nordeste. Facultad de Cs.veterinarias. Departamento de Clinica; Argentina Fil: Cholich, Luciana Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Nordeste. Facultad de Cs.veterinarias. Departamento de Clinica; Argentina Fil: Teibler, Gladys Pamela. Universidad Nacional del Nordeste. Facultad de Cs.veterinarias. Departamento de Clinica; Argentina Fil: Bogado, Facundo Ariel. Universidad Nacional del Nordeste. Facultad de Cs.veterinarias. Departamento de Clinica; Argentina Fil: Mussart, Norma Beatriz. Universidad Nacional del Nordeste. Facultad de Ciencias Veterinarias. Cátedra de Fisiología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

The toxic effects of Ipomoea carnea subsp. fistulosa were evaluated in guinea pigs by administration of dry leaves during 45 days. Swainsonine and calystegines B1, B2 and C1 were isolated and quantified. Clinical signs included emaciated and loss of body weight. Histological evaluation demonstrates numerous vacuoles in the cytoplasm of pancreas, liver and renal cells. Vacuolation was also evident in neurons of brain stem, mainly pontine nuclei. Neuronal lectin binding pattern showed a strong positive reaction to Con-A (Concanavalia ensiformis), WGA (Triticum vulgaris), sWGA (succinylated T. vulgaris) and LCA (Lens culinary). This result is coincident with the lectin histochemistry staining pattern of the vacuoles described in CNS of ruminants. We conclude that I. carnea subsp. fistulosa induces an intralysosomal accumulation of mannose-containing oligosaccharides in guinea pigs, which makes it a valuable animal model for the reproduction of induced a-mannosidosis. Fil: Cholich, Luciana Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste; Argentina. Universidad Nacional del Nordeste. Facultad de Ciencias Veterinarias; Argentina Fil: Gimeno, Eduardo Juan. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Cátedra de Patología General Veterinaria; Argentina Fil: Teibler, Gladys Pamela. Universidad Nacional del Nordeste. Facultad de Ciencias Veterinarias; Argentina Fil: Jorge, Nelly Lidia. Universidad Nacional del Nordeste. Facultad de Ciencias Exactas y Naturales y Agrimensura; Argentina Fil: Acosta, Ofelia Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste; Argentina. Universidad Nacional del Nordeste. Facultad de Ciencias Veterinarias; Argentina

The classical toxic effect produced by this Ipomoea fistulosa is due to the accumulation of oligosacharides in various tissues cell cytoplasm, mainly nervous, liver and lymphatic tissues, that leads to the cell vacuolitation. These effects are attributed to the presence of substances called swansonina and calisteginas in the vegetables, which produce inhibition of enzymes liposomales responsible for the metabolic carbohydrates. In natural conditions, the plant is not consumed by the animals. Its consumption occurs alone in determined times of year, for lack of sufficient pasture and it is more frequent in young animals. Since standard literature does not register any data on the chemical analysis of the kind Ipomoea, we report here the results on the extraction, isolation and spectroscopic identification of the present alkaloids in this plant., Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas

Ipomoea carnea var. fistulosa (Convolvulaceae) is a perenne poisonous plant, found throughout the Argentine Northeastern. The intoxication produces a lysosomal storage disease in goats, sheep and cattle. Five goats were fed with 50 g/kgBW/day of fresh leaves, flowers and stems of I. carnea, during 43–60 days. Hirsute coat, depression, difficulty to stand up, ataxia, hypermetria, wide–based stance, incoordination of muscular movements, intense tremors, spastic paresis, abnormal postural reactions, nystagmus, hyperreflexia, hypersensitivity to sound, head tilting and loss of equilibrium were observed in all treated animals. The histopathologic study revealed the presence of cytoplasmatic vacuolation mainly in medulla oblongata and cerebellum. Control animals did not show any alterations. We conclude that this poisoning causes central nervous system damage, being Purkinje cells the most severely affected.