Intoxicação aguda por fluorsilicato de sódio em bovinos / Acute sodium fluorosilicate poisoning in cattle

Background: Fluorine is a ubiquitous environmental element and fluoride poisoning in cattle is usually related to the ingestion of contaminated pastures or water, especially near industries, or mineral supplements with excessive amounts of this element. Cattle poisoning can be acute or chronic and is directly associated with the ingested dose and with the duration of exposure. The objective of this study is to report the epidemiological, clinical and anatomopathological aspects of an outbreak of acute sodium fluorosilicate intoxication in cattle.Case: Six 1-year-old, castrated male, mixed breed beef calves from a lot of 60 were found dead without previous clinical signs being observed. The calves died after ingesting a white, odorless, finely granular substance found by the owner near a road that intersected the property. The product was in an open package and identified as sodium fluorosilicate. Of the six dead calves, three were necropsied. Gross lesions were restricted to the digestive system and included varying degrees of hyperemia, hemorrhage, edema, and erosions in the pre-stomach and abomasum mucosae. The histological lesions observed in the three calves were characterized mainly by variable degenerative, necrotic and ulcerative changes in the epithelial lining of the forestomachs and abomasum. Partially (erosion) or totally (ulceration) bare lamina propria of forestomach papillae was covered by cellular debris and neutrophils. Multifocal lymphoid necrosis was seen in lymph nodes and spleen. Fluoride levels measured in the ruminal content of two necropsied calves were 55.2 and 9.17 mgF/kg of dry matter. After the diagnosis and discontinued exposure of the calves to the fluoride product, deaths ceased.Discussion: The diagnosis of acute sodium fluorosilicate intoxication in cattle in this study was based on epidemiological, clinical, and anatomopathological findings, and in the determination of fluoride levels in ruminal content.[...]

Intoxicação aguda por fluorsilicato de sódio em bovinos / Acute sodium fluorosilicate poisoning in cattle

Background: Fluorine is a ubiquitous environmental element and fluoride poisoning in cattle is usually related to the ingestion of contaminated pastures or water, especially near industries, or mineral supplements with excessive amounts of this element. Cattle poisoning can be acute or chronic and is directly associated with the ingested dose and with the duration of exposure. The objective of this study is to report the epidemiological, clinical and anatomopathological aspects of an outbreak of acute sodium fluorosilicate intoxication in cattle.Case: Six 1-year-old, castrated male, mixed breed beef calves from a lot of 60 were found dead without previous clinical signs being observed. The calves died after ingesting a white, odorless, finely granular substance found by the owner near a road that intersected the property. The product was in an open package and identified as sodium fluorosilicate. Of the six dead calves, three were necropsied. Gross lesions were restricted to the digestive system and included varying degrees of hyperemia, hemorrhage, edema, and erosions in the pre-stomach and abomasum mucosae. The histological lesions observed in the three calves were characterized mainly by variable degenerative, necrotic and ulcerative changes in the epithelial lining of the forestomachs and abomasum. Partially (erosion) or totally (ulceration) bare lamina propria of forestomach papillae was covered by cellular debris and neutrophils. Multifocal lymphoid necrosis was seen in lymph nodes and spleen. Fluoride levels measured in the ruminal content of two necropsied calves were 55.2 and 9.17 mgF/kg of dry matter. After the diagnosis and discontinued exposure of the calves to the fluoride product, deaths ceased.Discussion: The diagnosis of acute sodium fluorosilicate intoxication in cattle in this study was based on epidemiological, clinical, and anatomopathological findings, and in the determination of fluoride levels in ruminal content.[...](AU)

Intoxicação por monofluoroacetato em animais / Monofluoroacetate poisoning in animals

O monofluoroacetato (MF) ou ácido monofluoroacético é utilizado na Austrália e Nova Zelândia no controle populacional de mamíferos nativos ou exóticos. O uso desse composto é proibido no Brasil, devido ao risco de intoxicação de seres humanos e de animais, uma vez que a substância permanece estável por décadas. No Brasil casos recentes de intoxicação criminosa ou acidental têm sido registrados. MF foi identificado em diversas plantas tóxicas, cuja ingestão determina "morte súbita"; de bovinos na África do Sul, Austrália e no Brasil. O modo de ação dessa substância baseia-se na formação do fluorocitrato, seu metabólito ativo, que bloqueia competitivamente a aconitase e o ciclo de Krebs, o que reduz produção de ATP. As espécies animais têm sido classificadas nas quatro Categorias em função do efeito provocado por MF: (I) no coração, (II) no sistema nervoso central (III) sobre o coração e sistema nervoso central ou (IV) com sintomatologia atípica. Neste trabalho, apresenta-se uma revisão crítica atualizada sobre essa substância. O diagnóstico da intoxicação por MF é realizado pelo histórico de ingestão do tóxico, pelos achados clínicos e confirmado por exame toxicológico. Uma forma peculiar de degeneração hidrópico-vacuolar das células epiteliais dos túbulos uriníferos contorcidos distais tem sido considerada como característica dessa intoxicação em algumas espécies. O tratamento da intoxicação por MF é um desafio, pois ainda não se conhece um agente capaz de reverte-la de maneira eficaz; o desfecho geralmente é fatal.(AU)

Monofluoroacetate (MF) or monofluoroacetic acid is used in Australia and New Zealand for control of native or exotic mammals. The compounds are prohibited in Brazil, as they remain stable for decades and as risk for poisoning of animals and men exists. Cases of criminal and accidental poisonings have been reported in the country. MF was identified in several poisonous plants, the ingestion of which causes "sudden death"; in cattle in South Africa, Australia and Brazil. The poisoning leads in the Krebs cycle to the formation of fluorocitrate, its active metabolite, what competitively blocks aconitase in the cycle, with decrease in the production of ATP. Animal species have been classified into four categories regarding the effects caused by MF: (I) on heart, (II) heart and central nervous system, (III) central nertvous system or (IV) with atypical symptoms. In this paper, we present an updated critical review on MF poisoning. The diagnosis is made through the history of ingestion of the poison, by clinical findings and confirmation through toxicological examination. Vacuolarhydropic degeneration of the epithelial cells of the distal convoluted kidney tubules has been considered as characteristic of the poisoning in animal species. The treatment of MF poisoning is a challenge, since there is still not known any agent that effectively can reverse the poisoning, which generally is fatal.(AU)

Intoxicação por monofluoroacetato em animais / Monofluoroacetate poisoning in animals

O monofluoroacetato (MF) ou ácido monofluoroacético é utilizado na Austrália e Nova Zelândia no controle populacional de mamíferos nativos ou exóticos. O uso desse composto é proibido no Brasil, devido ao risco de intoxicação de seres humanos e de animais, uma vez que a substância permanece estável por décadas. No Brasil casos recentes de intoxicação criminosa ou acidental têm sido registrados. MF foi identificado em diversas plantas tóxicas, cuja ingestão determina "morte súbita"; de bovinos na África do Sul, Austrália e no Brasil. O modo de ação dessa substância baseia-se na formação do fluorocitrato, seu metabólito ativo, que bloqueia competitivamente a aconitase e o ciclo de Krebs, o que reduz produção de ATP. As espécies animais têm sido classificadas nas quatro Categorias em função do efeito provocado por MF: (I) no coração, (II) no sistema nervoso central (III) sobre o coração e sistema nervoso central ou (IV) com sintomatologia atípica. Neste trabalho, apresenta-se uma revisão crítica atualizada sobre essa substância. O diagnóstico da intoxicação por MF é realizado pelo histórico de ingestão do tóxico, pelos achados clínicos e confirmado por exame toxicológico. Uma forma peculiar de degeneração hidrópico-vacuolar das células epiteliais dos túbulos uriníferos contorcidos distais tem sido considerada como característica dessa intoxicação em algumas espécies. O tratamento da intoxicação por MF é um desafio, pois ainda não se conhece um agente capaz de reverte-la de maneira eficaz; o desfecho geralmente é fatal.

Monofluoroacetate (MF) or monofluoroacetic acid is used in Australia and New Zealand for control of native or exotic mammals. The compounds are prohibited in Brazil, as they remain stable for decades and as risk for poisoning of animals and men exists. Cases of criminal and accidental poisonings have been reported in the country. MF was identified in several poisonous plants, the ingestion of which causes "sudden death"; in cattle in South Africa, Australia and Brazil. The poisoning leads in the Krebs cycle to the formation of fluorocitrate, its active metabolite, what competitively blocks aconitase in the cycle, with decrease in the production of ATP. Animal species have been classified into four categories regarding the effects caused by MF: (I) on heart, (II) heart and central nervous system, (III) central nertvous system or (IV) with atypical symptoms. In this paper, we present an updated critical review on MF poisoning. The diagnosis is made through the history of ingestion of the poison, by clinical findings and confirmation through toxicological examination. Vacuolarhydropic degeneration of the epithelial cells of the distal convoluted kidney tubules has been considered as characteristic of the poisoning in animal species. The treatment of MF poisoning is a challenge, since there is still not known any agent that effectively can reverse the poisoning, which generally is fatal.

Avaliações clínico-patológicas e laboratoriais da intoxicação experimental por monofluoroacetato de sódio em ovinos / Clinic-pathological and laboratory aspects of experimental poisoning by sodium monofluoroacetate in sheep

O objetivo deste trabalho foi verificar se a administração de doses únicas e de frações diárias da dose letal de monofluoroacetato de sódio (MF) a ovinos induzem a clássica degeneração hidrópico-vacuolar (DHV) dos túbulos uriníferos contornados distais observada no rim de bovinos intoxicados por plantas brasileiras que causam "morte súbita" (PBCMS). MF foi administrado, por via oral, em doses únicas de 0,5 e 1,0mg/kg, cada dose para dois ovinos, e em doses subletais repetidas diariamente de 0,1mg/kg/dia, por quatro dias, e 0,2mg/kg/dia por seis dias, cada dose para um ovino. Todos os ovinos que receberam MF morreram, exceto um que recebeu 0,5mg/kg e não mostrou sintomas. A evolução da intoxicação variou de 3min a 33h5min. Clinicamente os animais apresentaram taquicardia, respiração abdominal, tremores musculares, ligeira perda de equilíbrio, por vezes cambaleavam, deitavam e apoiavam a cabeça no flanco. Na fase final, os ovinos caíam em decúbito lateral, esticavam os membros, faziam movimentos de pedalagem, apresentavam opistótono e morriam. O exame ecocardiográfico evidenciou dilatação cardíaca e redução da fração de encurtamento sistólico. A análise dos níveis séricos de uréia e creatinina revelou moderada a acentuada azotemia. MF provocou "morte súbita" em todos os ovinos que mostraram sintomas. À necropsia verificaram-se aurículas e veias jugulares, cavas, ázigos e pulmonares moderadamente ingurgitadas e, em alguns animais, edema pulmonar. O exame histopatológico revelou, em todos os ovinos, leve a acentuada DHV das células epiteliais dos túbulos contornados distais, associada à picnose nuclear. Adicionalmente, verificaram-se discreta vacuolização e, por vezes, necrose de coagulação de hepatócitos. Não encontramos referências a esse tipo peculiar de lesão, exceto das descrições sobre lesões renais associadas à ingestão de PBCMS e de recentes estudos em bovinos intoxicados com MF. Este trabalho demonstra, em ovinos, que tanto doses letais únicas quanto subdoses diárias de MF induzem a DHV dos túbulos uriníferos contornados distais associada à picnose nuclear.

The objective of this study was to verify if the ingestion of single doses of sodium monofluoroacetate (MF) and daily fractions of 1/2.5 and 1/5 of the lethal dose causes the same lesion as the one observed in the kidney of cattle poisoned by Brazilian sudden death causing plants (BSDCP). MF was administered orally in single doses of 0.5 and 1.0mg/kg to four sheep, and repeated daily doses of 0.1 and 0.2mg/kg to two others. Death occurred in five of six animals. The course of poisoning lasted from 3min to 33h5min. Clinically the animals presented palpitation, abdominal breathing, slight balance loss with sometimes swaying gait, they laid down and placed the head on their flank. In the "dramatic phase", all the sheep fell into lateral decubitus, stretched out the legs, made peddling movements, presented opistotonus, and died. The electrocardiographical examination showed heart dilatation and reduction of the systolic shortening fraction. Laboratory hematological exams revealed increased urea and creatinine. MF caused the clinical and pathological symptoms of "sudden death". At postmortem examination, heart auricles and jugular, cava, azygos and pulmonary veins of all animals were moderately engorged, and in some sheep, pulmonary edema was observed. Histopathology revealed hydropic-vacuolar degeneration (HVD) of the epithelial cells of the distal convoluted kidney tubules associated with nuclear picnosis in all the sheep. Vacuolation and less often necrosis of liver cells was seen in some cases. No references to that peculiar type of lesion could be found in the literature, except the description of kidney lesions in animals associated with the ingestion of BSDCP, and recent studies of MF poisoning in cattle. The present study demonstrated in sheep that single lethal doses or repeated doses of fractions of the lethal dose of MF causes HVD of the distal convoluted kidney tubules, associated with nuclear picnosis.

Avaliações clínico-patológicas e laboratoriais da intoxicação experimental por monofluoroacetato de sódio em ovinos / Clinic-pathological and laboratory aspects of experimental poisoning by sodium monofluoroacetate in sheep

O objetivo deste trabalho foi verificar se a administração de doses únicas e de frações diárias da dose letal de monofluoroacetato de sódio (MF) a ovinos induzem a clássica degeneração hidrópico-vacuolar (DHV) dos túbulos uriníferos contornados distais observada no rim de bovinos intoxicados por plantas brasileiras que causam "morte súbita" (PBCMS). MF foi administrado, por via oral, em doses únicas de 0,5 e 1,0mg/kg, cada dose para dois ovinos, e em doses subletais repetidas diariamente de 0,1mg/kg/dia, por quatro dias, e 0,2mg/kg/dia por seis dias, cada dose para um ovino. Todos os ovinos que receberam MF morreram, exceto um que recebeu 0,5mg/kg e não mostrou sintomas. A evolução da intoxicação variou de 3min a 33h5min. Clinicamente os animais apresentaram taquicardia, respiração abdominal, tremores musculares, ligeira perda de equilíbrio, por vezes cambaleavam, deitavam e apoiavam a cabeça no flanco. Na fase final, os ovinos caíam em decúbito lateral, esticavam os membros, faziam movimentos de pedalagem, apresentavam opistótono e morriam. O exame ecocardiográfico evidenciou dilatação cardíaca e redução da fração de encurtamento sistólico. A análise dos níveis séricos de uréia e creatinina revelou moderada a acentuada azotemia. MF provocou "morte súbita" em todos os ovinos que mostraram sintomas. À necropsia verificaram-se aurículas e veias jugulares, cavas, ázigos e pulmonares moderadamente ingurgitadas e, em alguns animais, edema pulmonar. O exame histopatológico revelou, em todos os ovinos, leve a acentuada DHV das células epiteliais dos túbulos contornados distais, associada à picnose nuclear. Adicionalmente, verificaram-se discreta vacuolização e, por vezes, necrose de coagulação de hepatócitos. Não encontramos referências a esse tipo peculiar de lesão, exceto das descrições sobre lesões renais associadas à ingestão de PBCMS e de recentes estudos em bovinos intoxicados com MF. Este trabalho demonstra, em ovinos, que tanto doses letais únicas quanto subdoses diárias de MF induzem a DHV dos túbulos uriníferos contornados distais associada à picnose nuclear.(AU)

The objective of this study was to verify if the ingestion of single doses of sodium monofluoroacetate (MF) and daily fractions of 1/2.5 and 1/5 of the lethal dose causes the same lesion as the one observed in the kidney of cattle poisoned by Brazilian sudden death causing plants (BSDCP). MF was administered orally in single doses of 0.5 and 1.0mg/kg to four sheep, and repeated daily doses of 0.1 and 0.2mg/kg to two others. Death occurred in five of six animals. The course of poisoning lasted from 3min to 33h5min. Clinically the animals presented palpitation, abdominal breathing, slight balance loss with sometimes swaying gait, they laid down and placed the head on their flank. In the "dramatic phase", all the sheep fell into lateral decubitus, stretched out the legs, made peddling movements, presented opistotonus, and died. The electrocardiographical examination showed heart dilatation and reduction of the systolic shortening fraction. Laboratory hematological exams revealed increased urea and creatinine. MF caused the clinical and pathological symptoms of "sudden death". At postmortem examination, heart auricles and jugular, cava, azygos and pulmonary veins of all animals were moderately engorged, and in some sheep, pulmonary edema was observed. Histopathology revealed hydropic-vacuolar degeneration (HVD) of the epithelial cells of the distal convoluted kidney tubules associated with nuclear picnosis in all the sheep. Vacuolation and less often necrosis of liver cells was seen in some cases. No references to that peculiar type of lesion could be found in the literature, except the description of kidney lesions in animals associated with the ingestion of BSDCP, and recent studies of MF poisoning in cattle. The present study demonstrated in sheep that single lethal doses or repeated doses of fractions of the lethal dose of MF causes HVD of the distal convoluted kidney tubules, associated with nuclear picnosis.(AU)

Evaluating a fluorosis hazard after a volcanic eruption.

The August, 1991 eruption of Mt. Hudson (Chile) deposited ash across southern Argentina and contributed to the deaths of thousands of grazing sheep. Early ash analysis revealed high levels of fluoride, a potential ash constituent toxic to humans and animals. In order to evaluate fluorosis as the cause of sheep deaths and to examine the possibility that similar ash and airborne toxins could also have an effect on the human population, we conducted an investigation that included health provider interviews, hospital record review, physical examination of sheep, determination of sheep urine fluoride levels, and complete constituent analysis of ash samples collected at proscribed distances from the volcano. Ash deposited farthest from the volcano had highest fluoride levels; all fluoride measurements were normal after rainfall. There were no signs or symptoms of fluorosis observed in sheep or humans. Sheep deaths resulted from physical, rather than chemical properties of the ash.