Evaluation of non-clinical toxicity of extract and vouacapans from fruits of Pterodon pubescens Benth.

Pterodon pubescens Benth. is widely used in folk medicine for the treatment of inflammatory conditions, with the activity attributed to the compounds with a vouacapan moiety, however, few studies report the toxicological evaluation of the extract and safety issues related to the species. Herein the non-clinical toxicity, in in vivo and in vitro tests, of dichloromethane crude extract of Pterodon pubescens fruits (PPE) and vouacapan diterpene furan isomer´s mixture (1:1) 6α-hydroxy-7ß-acetoxy-vouacapan-17ß-oate methyl ester and 6α-acetoxy-7ß-hydroxy-vouacapan-17ß-oate methyl ester isomers (VDFI mixture) is reported. Toxicological evaluation of 110-day repeated dose oral toxicity study, as hematological, biochemical, and histopathological parameters demonstrated that animals (male and female Wistar rats) treated with PPE presented no signs of toxicity, nevertheless daily high dose administration (500 mg/Kg) altered the metabolic homeostasis of animals that manifested microgoticular hepatic steatosis. Biochemical and histopathological results of animals (female Swiss mice) treated daily with VDFI mixture, at the highest dose (300 mg/Kg), indicated liver toxicity in one animal causing acute hepatotoxicity. Alkaline Comet assay demonstrated that PPE and VDFI mixture increased the percentage of DNA fragmentation without interfering with the tail moment parameter, but only VDFI mixture (30 µg/mL) presented statistical difference. In the micronucleus induction test, PPE and VDFI mixture did not demonstrate mutagenic potential. Our data provide evidence for the safety use of PPE and VDFI mixture in lower doses enabling further clinical studies and the development of herbal medicine.

Anti-acetylcholinesterase and toxicity against Artemia salina of chitosan microparticles loaded with essential oils of Cymbopogon flexuosus, Pelargonium x ssp and Copaifera officinalis.

Essential oils (EOs) are bioactive compounds with therapeutic potential for use as alternatives or as support to conventional treatments. However, EOs present limitations, such as sensibility to environmental factors, which can be overcome through microencapsulation. The objective of this study was to produce, by spray drying, chitosan microparticles (CMs) loaded with EO of Lemongrass (Cymbopogon flexuosus), Geranium (Pelargonium x ssp) and Copaiba (Copaifera officinalis). Physicochemical and biological characterization of these microparticles showed that CMs presented spherical morphology, had an average size range of 2-3 µm with positive zeta potential (ZP) values, and enhanced thermal stability, compared to free EO. The encapsulation efficiency (EE) ranged from 4.8-58.6%, depending on the oil's properties. In vitro EO release from CMs was determined at different pHs, with 94% release observed in acid media. All microparticles were non-hemolytic at concentrations of up to 0.1 mg·mL-1. EOs and CMs presented acetylcholinesterase (AChE) inhibition activity (IC 50 ranged from 11.92 to 28.18 µg·mL-1). Geranium and Copaiba EOs presented higher toxicity against Artemia salina, and greater inhibition of acetylcholinesterase, indicating potential bioactivity for Alzheimer's disease (AD). Our findings demonstrate that CM systems may show promise for the controlled release of these EOs.

Acrocarpus fraxinifolius Wight and Arn. Bark; phenolics, toxicity studies, antioxidant and anti-inflammatory activities

The purpose of the survey was to determine acute & chronic toxicity; in vivo antioxidant and anti-inflammatory actions of the different extracts of A. fraxinifolius Wight and Arn bark; along with estimation of the phenolic, flavonoidal contents and investigation of phenolic metabolites that may attribute to the activities. LD50 of the total ethanol extract (TEE) was 7.1 g/kg b. wt, the radical scavenging activity of DPPH showed 60.31% inhibition, FRAP ability and ABTS+ activity showed 55.024 and 67.217 µmol Trolox/100 g dry weight, respectively. TEE followed by ethyl acetate extract (EAE) at 100 mg/kg b.w exhibited the highest in vivo antioxidant activity (94.51% and 91.08% potency, respectively) compared with Vit E (100%). The TEE & EAE exhibited the highest anti-inflammatory activity (3.81±0.08 & 3.79±.0.04) respectively in comparison with indomethacin 3.83±0.01 measured as edema diameter after 4 hours of extract administration. The total phenolic and total flavonoid contents in the total ethanol extract (TEE) estimated as gallic acid and catechin equivalents were 61.06± 0.08 µg eq GA/g, 40.33± 0.20 µg CE/g extract respectively. EAE revealed five phenolic acids and eight flavonoid compounds isolated for the first time from the plant

Poisoning by Enterolobium contortisiliquum pods in calves showing photosensitization and digestive lesions / [Lesões digestivas e fotossensibilização em bezerros intoxicados pelas favas de Enterolobium contortisiliquum]

Este trabalho descreve um surto de rumenite e abomasite decorrente de sobrecarga de carboidratos em um rebanho de 238 bezerros, com idades entre 12 e 15 meses, causada pela ingestão dos frutos de Enterolobium contortisiliquum. As taxas de morbidade, mortalidade e letalidade foram de, respectivamente, 12,7%, 5,2% e 42,1%. Clinicamente, os bovinos apresentaram fotossensibilização, salivação e diarreia. Os achados de necropsia foram semelhantes nos dois bezerros necropsiados e consistiram de fotodermatite e rumenite ulcerativa multifocal, subaguda a crônica, e abomasite. A relevância deste relato é que, pela primeira vez, foi possível associar a ocorrência da rumenite devido à sobrecarga de carboidratos com a intoxicação espontânea por E. contortisiliquum em bovinos, confirmando achados anteriormente descritos em experimentos realizados com ovinos.(AU)

Poisoning by Enterolobium contortisiliquum pods in calves showing photosensitization and digestive lesions / [Lesões digestivas e fotossensibilização em bezerros intoxicados pelas favas de Enterolobium contortisiliquum]

Este trabalho descreve um surto de rumenite e abomasite decorrente de sobrecarga de carboidratos em um rebanho de 238 bezerros, com idades entre 12 e 15 meses, causada pela ingestão dos frutos de Enterolobium contortisiliquum. As taxas de morbidade, mortalidade e letalidade foram de, respectivamente, 12,7%, 5,2% e 42,1%. Clinicamente, os bovinos apresentaram fotossensibilização, salivação e diarreia. Os achados de necropsia foram semelhantes nos dois bezerros necropsiados e consistiram de fotodermatite e rumenite ulcerativa multifocal, subaguda a crônica, e abomasite. A relevância deste relato é que, pela primeira vez, foi possível associar a ocorrência da rumenite devido à sobrecarga de carboidratos com a intoxicação espontânea por E. contortisiliquum em bovinos, confirmando achados anteriormente descritos em experimentos realizados com ovinos.(AU)

Anti-tick effect and cholinesterase inhibition caused by Prosopis juliflora alkaloids: in vitro and in silico studies / Efeito carrapaticida e inibição da acetilcolinesterase por alcaloides de Prosopis juliflora: estudos in vitro e in silico

We investigated the in vitro acaricide activity of the methanolic extract (ME) and alkaloid-rich fraction (AF) of Prosopis juliflora on Rhipicephalus microplus and correlated this effect with acetylcholinesterase (AChE) inhibition. The acaricide activity was evaluated using adult and larval immersion tests. Also, we studied the possible interaction mechanism of the major alkaloids present in this fraction via molecular docking at the active site of R. microplus AChE1 (RmAChE1). Higher reproductive inhibitory activity of the AF was recorded, with effective concentration (EC50) four times lower than that of the ME (31.6 versus 121 mg/mL). The AF caused mortality of tick larvae, with lethal concentration 50% (LC50) of 13.8 mg/mL. Both ME and AF were seen to have anticholinesterase activity on AChE of R. microplus larvae, while AF was more active with half-maximal inhibitory concentration (IC50) of 0.041 mg/mL. The LC-MS/MS analyses on the AF led to identification of three alkaloids: prosopine (1), juliprosinine (2) and juliprosopine (3). The molecular docking studies revealed that these alkaloids had interactions at the active site of the RmAChE1, mainly relating to hydrogen bonds and cation-pi interactions. We concluded that the alkaloids of P. juliflora showed acaricide activity on R. microplus and acted through an anticholinesterase mechanism.(AU)

A atividade carrapaticida in vitro do extrato metanólico (EM) e da fração de alcaloides (FA) de Prosopis juliflora foi investigada, frente ao Rhipicephalus microplus, e relacionada com a inibição da enzima acetilcolinesterase (AChE). A predição in silico das interações de alcaloides dessa fração com a AChE1 de R. microplus (RmAChE1) foi realizada por acoplamento molecular. A atividade carrapaticida foi avaliada, utilizando-se os ensaios de imersão de adultos e larvas. Maior efeito sobre parâmetros reprodutivos de teleóginas foi verificado para a FA, com valor de Concentração Efetiva 50% (CE50) (31.6 mg/mL), quatro vezes menor do que o valor do EM (121 mg/mL). A FA induziu mortalidade de larvas (Concentração Letal de 50% - CL50 = 13,8 mg/mL). A inibição da atividade da AChE de larvas do carrapato foi observada para EM e FA, sendo a FA mais ativa (Concentração Inibitória 50%- CI50 de 0,041mg/mL). As análises químicas da FA permitiram a identificação dos alcaloides prosopina (1), juliprosinina (2) e juliprosopina (3). No ensaio in silico, observou-se que esses alcaloides podem interagir com o sítio ativo da RmAChE1, principalmente por ligações de hidrogênio e interações cátion-pi. Os alcaloides de P. juliflora têm atividade carrapaticida contra R. microplus, atuando através do mecanismo anticolinesterásico.(AU)

Evaluation of cytotoxic potential, oral toxicity, genotoxicity, and mutagenicity of organic extracts of Pityrocarpa moniliformis.

The objective of this study was to determine the cytotoxicity of organic extracts of P. moniliformis in vitro and identify the acute toxicity and genotoxicity in vivo. The leaves were extracted using three organic solvents (cyclohexane [EP1], ethyl acetate [EP2], and methanol [EP3]). Phytochemical qualitative analysis was performed by thin layer chromatography (TLC). Cytotoxicity tests were performed on human embryonic kidney (HEK) cells and J774 murine macrophages. Acute toxicity in mice was measured after intraperitoneal (ip) administration of 2000 mg/kg, while evaluation of genotoxicity and mutagenicity were assessed using the comet assay and the micronucleus (MN) test, respectively. The TLC analysis of the extracts revealed the presence of flavonoids, triterpenes, steroids, and saponins. In the cytotoxicity assay, extracts EP1 and EP3 altered proliferation of HEK cells, and all organic extracts increased the viability of J774 cells. In the toxicity tests, no deaths or behavioral alterations were observed in mice exposed to the acute dose of the extracts. Although some extracts led to changes in hematological and histological parameters, these results did not indicate physiological changes. In relation to the MN test and comet assay, no significant changes were detected in the DNA of the animals tested with the extracts EP1, EP2, and EP3. Thus, extracts of P. moniliformis were not considered to be toxic and did not induce formation of MN or damage to cellular DNA in the genotoxicity tests.

Intoxicação aguda pela ingestão de Samanea tubulosa em bovino / Acute intoxication by ingestion of Samanea tubulosa in bovine

As intoxicações em animais de produção causadas por plantas são bastante relatadas, resultando em perdas econômicas diretas causadas pela morte dos animais, diminuição dos índices produtivos e reprodutivos, além de aumentar a ocorrência e susceptibilidade a outras doenças. Já as perdas indiretas, incluem os custos para o controle das plantas tóxicas nas pastagens, além das medidas de manejo como a utilização de cercas e o pastoreio alternativo para evitar as intoxicações, assim como também os gastos associados ao diagnóstico e tratamento. No presente trabalho relatou-se a intoxicação de um bovino de raça Girolando de 11 anos pelo consumo da planta conhecida como bordão-de-velho (Samanea tubulosa). As alterações pós-mortem macro e microscópicas demonstraram que a causa provável de morte foi a síndrome de disfunção de múltiplos órgãos. Estudos in vivo são necessários para conhecer mais a fundo o potencial tóxico desta planta.

Intoxications in production animals caused by plants are well reported, resulting direct losses caused by the death of animals, by the reduction of productive and reproductive indexes, as well as increase in the frequence and susceptibility to other diseases. Indirect losses can be attributed to control plants in pastures, in addition to manipulation measures, such as use of fences and alternative grazing to avoid intoxication. The present work reported the intoxication of an 11-year-old female breed of cattle by the consumption of the plant known as bordão-develho (Samanea tubulosa). Macro and microscopic finds demonstrate that the probable cause is multiple organ dysfunction syndrome. In vivo studies are needed to know more about the toxic potential of this plant.

Intoxicação aguda pela ingestão de Samanea tubulosa em bovino / Acute intoxication by ingestion of Samanea tubulosa in bovine

As intoxicações em animais de produção causadas por plantas são bastante relatadas, resultando em perdas econômicas diretas causadas pela morte dos animais, diminuição dos índices produtivos e reprodutivos, além de aumentar a ocorrência e susceptibilidade a outras doenças. Já as perdas indiretas, incluem os custos para o controle das plantas tóxicas nas pastagens, além das medidas de manejo como a utilização de cercas e o pastoreio alternativo para evitar as intoxicações, assim como também os gastos associados ao diagnóstico e tratamento. No presente trabalho relatou-se a intoxicação de um bovino de raça Girolando de 11 anos pelo consumo da planta conhecida como bordão-de-velho (Samanea tubulosa). As alterações pós-mortem macro e microscópicas demonstraram que a causa provável de morte foi a síndrome de disfunção de múltiplos órgãos. Estudos in vivo são necessários para conhecer mais a fundo o potencial tóxico desta planta.(AU)

Intoxications in production animals caused by plants are well reported, resulting direct losses caused by the death of animals, by the reduction of productive and reproductive indexes, as well as increase in the frequence and susceptibility to other diseases. Indirect losses can be attributed to control plants in pastures, in addition to manipulation measures, such as use of fences and alternative grazing to avoid intoxication. The present work reported the intoxication of an 11-year-old female breed of cattle by the consumption of the plant known as bordão-develho (Samanea tubulosa). Macro and microscopic finds demonstrate that the probable cause is multiple organ dysfunction syndrome. In vivo studies are needed to know more about the toxic potential of this plant.(AU)

Photosensitization in cattle caused by spontaneous and experimentally ingestion of Stryphnodendron fissuratum

Background: Stryphnodendron fissuratum is a tree from the Brazilian Cerrado. Its fruit is toxic to cattle and can cause clinical digestive signs, hepatogenous photosensitization, and abortion. Cases of poisoning in cattle, goats and guinea pigs have been experimentally reproduced; however, photosensitization could not be reproduced. The aim of this work was to describe an outbreak of natural poisoning and experimental reproduction in cattle, both with hepatogenous photosensitization.Materials, Methods & Results: Its described and natural outbreak and an experimental poisoning. In the outbreak, three bovines in the acute phase and three in the chronic phase were examined. Blood samples were collected from all of these animals in order to measure serum levels of aspartate aminotransferase (AST), gamma-glutamyl transferase (GGT), urea, and creatinine. The first three animals underwent necropsy and histopathological evaluation. The experiment was conducted with two nine-month-old calves that received an oral paste made with crushed S. fissuratum fruits mixed with water. These fruits were collected at a farm at which cattle poisoning cases had occurred. Blood samples were collected in order to measure serum levels of AST, GGT, urea, and creatinine, before plant administration and then daily during the experimental period. Skin biopsies were taken before plant administration and new one after the first signs of skin lesions. The natural outbreak affected 52 of 160 bovine (31 calves and 21 cows) in the lot. Two calves and 14 cows died. Clinical signs consisted of depression, ataxia, incoordination, behavioral changes, decubitus, and death. One animal that died and 36 others that recovered had photodermatitis. Necropsy findings in the animals consisted of bad corporal condition, pale kidneys, evidence of liver lobular pattern, dry rumen contents, and full bladder.[...](AU)

Photosensitization in cattle caused by spontaneous and experimentally ingestion of Stryphnodendron fissuratum

Background: Stryphnodendron fissuratum is a tree from the Brazilian Cerrado. Its fruit is toxic to cattle and can cause clinical digestive signs, hepatogenous photosensitization, and abortion. Cases of poisoning in cattle, goats and guinea pigs have been experimentally reproduced; however, photosensitization could not be reproduced. The aim of this work was to describe an outbreak of natural poisoning and experimental reproduction in cattle, both with hepatogenous photosensitization.Materials, Methods & Results: Its described and natural outbreak and an experimental poisoning. In the outbreak, three bovines in the acute phase and three in the chronic phase were examined. Blood samples were collected from all of these animals in order to measure serum levels of aspartate aminotransferase (AST), gamma-glutamyl transferase (GGT), urea, and creatinine. The first three animals underwent necropsy and histopathological evaluation. The experiment was conducted with two nine-month-old calves that received an oral paste made with crushed S. fissuratum fruits mixed with water. These fruits were collected at a farm at which cattle poisoning cases had occurred. Blood samples were collected in order to measure serum levels of AST, GGT, urea, and creatinine, before plant administration and then daily during the experimental period. Skin biopsies were taken before plant administration and new one after the first signs of skin lesions. The natural outbreak affected 52 of 160 bovine (31 calves and 21 cows) in the lot. Two calves and 14 cows died. Clinical signs consisted of depression, ataxia, incoordination, behavioral changes, decubitus, and death. One animal that died and 36 others that recovered had photodermatitis. Necropsy findings in the animals consisted of bad corporal condition, pale kidneys, evidence of liver lobular pattern, dry rumen contents, and full bladder.[...]

Malformações em pequenos ruminantes no semiárido da Bahia: aspectos epidemiológicos, clínico-patológicos e radiológicos / Malformations in small ruminants in the semi-arid region of Bahia: epidemiological, clinical-pathological and radiological aspects

O objetivo do presente trabalho é descrever os principais aspectos epidemiológicos, clínico-patológicos e radiológicos de malformações em pequenos ruminantes no semiárido do estado da Bahia. Foram realizadas visitas técnicas em 41 propriedades rurais no município de Uauá, Bahia, e em cada uma delas foi aplicado um questionário epidemiológico. Adicionalmente, quando se observavam casos de malformações, os animais eram avaliados vivos ou mortos. Foram necropsiados oito animais (1, 2, 3, 4, 5, 6, 7 e 8), e dois (7 e 8) foram submetidos a exame radiográfico. Sobre a alimentação do rebanho, 40 (97,56%) produtores rurais relataram o livre acesso de seus animais à vegetação nativa. Em relação à presença de Mimosa tenuiflora, 5 (12,2%) informaram que os animais tinham acesso à planta, 15 (36,6 %) disseram que tinham pouco contato, enquanto que 21 (51,2 %) relataram que não havia nenhum contato com a planta, pois essa espécie não estava presente em número relevante na região. Vinte e cinco dos 41 proprietários (60,98%) relataram o consumo de Poincianella pyramidalis. Foi constatado ainda que na maioria das propriedades havia muitas áreas invadidas por P. pyramidalis (80-90% da vegetação). As principais anormalidades relatadas pelos entrevistados em 36 propriedades foram artrogripose (87,80%), agnatia [22 (53,66%)], desvio lateral da mandíbula [11 (26,82%)], escoliose [6 (14,63%)], micrognatia [6 (14,63%)], fenda palatina [4 (9,75%)], crânio aumentado de tamanho [4 (9,75%)], microftalmia [2 (4,88%)], braquignatismo [1 (2,43%)], exoftalmia [1 (2,43%)] e deformidades múltiplas no crânio [1 (2,43%)]. No exame clínico de 13 animais com malformações, as principais alterações foram artrogripose bilateral dos membros torácicos (6/13); queilosquise (2/13); micrognatia (1/13) e má oclusão dentária (1/13). Considerando que algumas dessas malformações foram reproduzidas experimentalmente em caprinos pode-se sugerir P. pyramidalis como mais uma planta teratogênica para ruminantes no Nordeste do Brasil.(AU)

The aim of this paper is to describe the epidemiological, clinical-pathological and radiological aspects of malformations in small ruminants in the semi-arid state of Bahia. Technical visits were carried out in 41 rural properties in the city of Uauá, Bahia, and in each of them, an epidemiological questionnaire was applied. In addition, when malformations were observed, the animals were evaluated alive or dead. Eight animals (1, 2, 3, 4, 5, 6, 7 and 8) were necropsied, and two (7 and 8) were submitted to radiographic examination. Regarding the feeding of the herd, 40 (97.56%) farmers reported the free access of their animals to the native vegetation. Regarding the presence of Mimosa tenuiflora, 5 (12.2%) said that the animals had access to the plant, 15 (36.6%) was informed they had little contact, while 21 (51.2%) reported that there was no contact with the plant, because this species were not present in a relevant number in the region. Twenty five out of 41 owners (60.98%) reported the consumption of Poincianella pyramidalis. It was also verified that in the majority of the properties there were many areas invaded by P. pyramidalis (80-90% of the vegetation). The main abnormalities reported by the interviewees on 36 properties were arthrogryposis (87.80%), agnatia [22 (53.66%)], lateral deviation of the mandible [11 (26.82%)], scoliosis [6 (14.63%)], micrognathia [6 (14.63%)], cleft palate [4 (9.75%)], skull enlarged in size [4 (9.75%)], microphthalmia [2 (4.88%)], braquignatism [1 (2.43%)], exophthalmia [1 (2.43%)] and, multiple deformities in the skull [1 (2.43%)]. In the clinical examination of 13 animals with malformations, the main alterations were bilateral arthrogryposis of the thoracic limbs (6/13); cleft lip (2/13); micrognathia (1/13) and dental malocclusion (1/13). Considering that some of these malformations were reproduced experimentally in goats, it is possible to suggest P. pyramidalis as another teratogenic plant for ruminants in Northeast Brazil.(AU)

Malformações congênitas e abortos induzidos experimentalmente pela ingestão de Poincianella pyramidalis (Tul. ) L. P. Queiroz (catingueira) em ovelhas / Congenital malformations and abortions induced experimentally by the ingestion of Poincianella pyramidalis (Tul. ) L. P. Queiroz (catingueira) in sheep

Poincianella pyramidalis (catingueira) é uma planta tóxica associada a abortos, perdas embrionárias e malformações em caprinos e animais de laboratório. Surtos e casos esporádicos de intoxicação espontânea em ovinos vem sendo relatados nos últimos cinco anos no agreste de Pernambuco. Devido à ocorrência destes casos espontâneos e a escassez de pesquisas na espécie ovina, o objetivo desse trabalho foi realizar um estudo experimental para avaliação dos efeitos teratogênicos de P. pyramidalis em ovelhas. No experimento foram utilizadas 16 ovelhas e três carneiros, sem raça definida (SRD). As fêmeas foram divididas em quatro grupos, com quatro animais por grupo e mantidas em baias individuais, foram submetidas a sincronização do estro e acasalamento por monta natural, após 30 dias foi realizado o diagnóstico para confirmação da gestação. Os grupos foram denominados como: grupo 1 (G1), grupo 2 (G2), grupo 3 (G3) e grupo 4 (G4). No G1 (controle) as ovelhas foram alimentadas com 1% de suplementação concentrada (SC) baseado no peso vivo (PV) e 2% de volumoso a base de silagem de milho (SM), com uma ingestão diária de 3% de matéria seca (MS) com base no PV. No G2 a alimentação era constituída de 1% de SC com base no PV e 2% de volumoso. Sendo que destes 2% de volumoso, 50% era feno de P. pyramidalis e os outros 50% de SM. No G3 a alimentação era constituída de 1% de SC com base no PV e 2% de volumoso. Sendo que destes 2% de volumoso, 80% foi de feno de P. pyramidalis e os outros 20% de SM. No G4 as ovelhas foram alimentadas com 1% de SC com base no PV e o volumoso constituído de 100% de feno de P. pyramidalis. Todos os grupos receberam SC à base de farelo de milho, farelo de algodão, sal mineral especifico para ovinos e água ad libitum. Mensalmente os animais foram submetidos à ultrassonografia para detecção de perdas embrionárias ou fetais. Foram realizados exames sorológicos para Neospora caninum e Toxoplasma gondii antes da introdução dos animais no experimento. Os fetos com malformações foram avaliados no setor de Patologia da UFRPE / Unidade Acadêmica de Garanhuns (UAG) para descrição das lesões. No G2, ocorreram cinco casos de malformações de oito cordeiros nascidos. No G3, ocorreram quatro casos de malformação, sendo um decorrente de aborto. No G4, uma ovelha abortou e as outras três pariram quatro fetos malformados. As principais malformações encontradas no trabalho foram artrogripose, palatosquise, queilosquise, hipoplasia da mandíbula, aplasia do osso incisivo, malformações de olho e língua, polidactilia e monodactilia. Nos grupos de maior percentual de ingestão da planta foram observadas maiores quantidades de malformações e chamou a atenção a ocorrência de retenção de placenta e a alta frequência de mortalidade perinatal nos cordeiros que apresentaram algum tipo de malformação. Demonstrou-se com esse trabalho que a P. pyramidalis é uma importante causa de malformação congênita, aborto e mortalidade perinatal em ovinos, sendo de extrema importância que se mantenha as ovelhas prenhes fora do alcance desta planta durante todo o período gestacional.(AU)

Poincianella pyramidalis (catingueira) is a toxic plant associated with abortions, embryonic losses and malformations in goats and laboratory animals. Outbreaks and sporadic cases of spontaneous intoxication in sheep have been reported in the last five years in the agreste of Pernambuco. Due to the occurrence of these spontaneous cases and the lack of researches in sheep, an experimental study was carried out to evaluate the teratogenic effects of P. pyramidalis on sheep. In the experiment, 16 female and three male sheeps, mixed breed, were used. Females were divided in four groups, with four animals per group and maintained in individual stalls, underwent estrus synchronization and mating by natural mating and after 30 days the diagnosis was made to confirm gestation. Groups were named group 1 (G1), group 2 (G2), group 3 (G3), and group 4 (G4). In G1 (control) the ewes were fed with 1% of concentrate supplementation (CS) based on live weight (LW) and 2% of maize silage (MS) with a daily intake of 3% dry matter (DM) based on LW. In G2 feeding was constituted of 1% of CS based on LW and 2% of forage, including 2% of roughage, 50% was hay of P. pyramidalis and the other 50% of DM. In G3 feed was constituted of 1% of CS based on LW and 2% of roughage. Among these 2% of roughage, 80% was hay of P. pyramidalis and the other 20% of DM. In G4 the sheep were fed with 1% CS based on the LW and the roughage consisting of 100% P. pyramidalis hay. All groups received CS with corn meal, cottonseed meal, mineral salt specific for sheep and water ad libitum. Animals were monthly submitted to ultrasonography to detect embryonic or fetal losses. Serological tests were performed for Neospora caninum and Toxoplasma gondii before introduction of the animals in the experiment. Fetuses with malformations were evaluated in the Laboratory of Animal Anatomy and Pathology of the Academic Unit of Garanhuns (UAG), UFRPE, to describe the lesions. In G2, there were five cases of malformations of eight born lambs. In G3, there were four cases of malformation, one due to abortion. In G4, one sheep aborted and the other three gave birth to four malformed fetuses. Main malformations found in the study were arthrogryposis, palatoschisis, chylosquisis, hypoplasia of the mandible, aplasia of the incisive bone, malformations of the eye and tongue, polidactyly and monodactyly. In the groups with higher doses, larger numbers of malformations were observed, and the occurrence of placental retention and the high frequency of perinatal mortality in lambs presenting some type of malformation were noted. It has been demonstrated that P. pyramidalis is an important cause of congenital malformation, abortion and perinatal mortality in sheep, therefore keeping pregnant sheep away from this plant throughout the gestation period is utmost important.(AU)

Malformações em pequenos ruminantes no semiárido da Bahia: aspectos epidemiológicos, clínico-patológicos e radiológicos / Malformations in small ruminants in the semi-arid region of Bahia: epidemiological, clinical-pathological and radiological aspects

O objetivo do presente trabalho é descrever os principais aspectos epidemiológicos, clínico-patológicos e radiológicos de malformações em pequenos ruminantes no semiárido do estado da Bahia. Foram realizadas visitas técnicas em 41 propriedades rurais no município de Uauá, Bahia, e em cada uma delas foi aplicado um questionário epidemiológico. Adicionalmente, quando se observavam casos de malformações, os animais eram avaliados vivos ou mortos. Foram necropsiados oito animais (1, 2, 3, 4, 5, 6, 7 e 8), e dois (7 e 8) foram submetidos a exame radiográfico. Sobre a alimentação do rebanho, 40 (97,56%) produtores rurais relataram o livre acesso de seus animais à vegetação nativa. Em relação à presença de Mimosa tenuiflora, 5 (12,2%) informaram que os animais tinham acesso à planta, 15 (36,6 %) disseram que tinham pouco contato, enquanto que 21 (51,2 %) relataram que não havia nenhum contato com a planta, pois essa espécie não estava presente em número relevante na região. Vinte e cinco dos 41 proprietários (60,98%) relataram o consumo de Poincianella pyramidalis. Foi constatado ainda que na maioria das propriedades havia muitas áreas invadidas por P. pyramidalis (80-90% da vegetação). As principais anormalidades relatadas pelos entrevistados em 36 propriedades foram artrogripose (87,80%), agnatia [22 (53,66%)], desvio lateral da mandíbula [11 (26,82%)], escoliose [6 (14,63%)], micrognatia [6 (14,63%)], fenda palatina [4 (9,75%)], crânio aumentado de tamanho [4 (9,75%)], microftalmia [2 (4,88%)], braquignatismo [1 (2,43%)], exoftalmia [1 (2,43%)] e deformidades múltiplas no crânio [1 (2,43%)]. No exame clínico de 13 animais com malformações, as principais alterações foram artrogripose bilateral dos membros torácicos (6/13); queilosquise (2/13); micrognatia (1/13) e má oclusão dentária (1/13). Considerando que algumas dessas malformações foram reproduzidas experimentalmente em caprinos pode-se sugerir P. pyramidalis como mais uma planta teratogênica para ruminantes no Nordeste do Brasil.(AU)

The aim of this paper is to describe the epidemiological, clinical-pathological and radiological aspects of malformations in small ruminants in the semi-arid state of Bahia. Technical visits were carried out in 41 rural properties in the city of Uauá, Bahia, and in each of them, an epidemiological questionnaire was applied. In addition, when malformations were observed, the animals were evaluated alive or dead. Eight animals (1, 2, 3, 4, 5, 6, 7 and 8) were necropsied, and two (7 and 8) were submitted to radiographic examination. Regarding the feeding of the herd, 40 (97.56%) farmers reported the free access of their animals to the native vegetation. Regarding the presence of Mimosa tenuiflora, 5 (12.2%) said that the animals had access to the plant, 15 (36.6%) was informed they had little contact, while 21 (51.2%) reported that there was no contact with the plant, because this species were not present in a relevant number in the region. Twenty five out of 41 owners (60.98%) reported the consumption of Poincianella pyramidalis. It was also verified that in the majority of the properties there were many areas invaded by P. pyramidalis (80-90% of the vegetation). The main abnormalities reported by the interviewees on 36 properties were arthrogryposis (87.80%), agnatia [22 (53.66%)], lateral deviation of the mandible [11 (26.82%)], scoliosis [6 (14.63%)], micrognathia [6 (14.63%)], cleft palate [4 (9.75%)], skull enlarged in size [4 (9.75%)], microphthalmia [2 (4.88%)], braquignatism [1 (2.43%)], exophthalmia [1 (2.43%)] and, multiple deformities in the skull [1 (2.43%)]. In the clinical examination of 13 animals with malformations, the main alterations were bilateral arthrogryposis of the thoracic limbs (6/13); cleft lip (2/13); micrognathia (1/13) and dental malocclusion (1/13). Considering that some of these malformations were reproduced experimentally in goats, it is possible to suggest P. pyramidalis as another teratogenic plant for ruminants in Northeast Brazil.(AU)

Malformações congênitas e abortos induzidos experimentalmente pela ingestão de Poincianella pyramidalis (Tul. ) L. P. Queiroz (catingueira) em ovelhas / Congenital malformations and abortions induced experimentally by the ingestion of Poincianella pyramidalis (Tul. ) L. P. Queiroz (catingueira) in sheep

Poincianella pyramidalis (catingueira) é uma planta tóxica associada a abortos, perdas embrionárias e malformações em caprinos e animais de laboratório. Surtos e casos esporádicos de intoxicação espontânea em ovinos vem sendo relatados nos últimos cinco anos no agreste de Pernambuco. Devido à ocorrência destes casos espontâneos e a escassez de pesquisas na espécie ovina, o objetivo desse trabalho foi realizar um estudo experimental para avaliação dos efeitos teratogênicos de P. pyramidalis em ovelhas. No experimento foram utilizadas 16 ovelhas e três carneiros, sem raça definida (SRD). As fêmeas foram divididas em quatro grupos, com quatro animais por grupo e mantidas em baias individuais, foram submetidas a sincronização do estro e acasalamento por monta natural, após 30 dias foi realizado o diagnóstico para confirmação da gestação. Os grupos foram denominados como: grupo 1 (G1), grupo 2 (G2), grupo 3 (G3) e grupo 4 (G4). No G1 (controle) as ovelhas foram alimentadas com 1% de suplementação concentrada (SC) baseado no peso vivo (PV) e 2% de volumoso a base de silagem de milho (SM), com uma ingestão diária de 3% de matéria seca (MS) com base no PV. No G2 a alimentação era constituída de 1% de SC com base no PV e 2% de volumoso. Sendo que destes 2% de volumoso, 50% era feno de P. pyramidalis e os outros 50% de SM. No G3 a alimentação era constituída de 1% de SC com base no PV e 2% de volumoso. Sendo que destes 2% de volumoso, 80% foi de feno de P. pyramidalis e os outros 20% de SM. No G4 as ovelhas foram alimentadas com 1% de SC com base no PV e o volumoso constituído de 100% de feno de P. pyramidalis. Todos os grupos receberam SC à base de farelo de milho, farelo de algodão, sal mineral especifico para ovinos e água ad libitum. Mensalmente os animais foram submetidos à ultrassonografia para detecção de perdas embrionárias ou fetais. Foram realizados exames sorológicos para Neospora caninum e Toxoplasma gondii antes da introdução dos animais no experimento. Os fetos com malformações foram avaliados no setor de Patologia da UFRPE / Unidade Acadêmica de Garanhuns (UAG) para descrição das lesões. No G2, ocorreram cinco casos de malformações de oito cordeiros nascidos. No G3, ocorreram quatro casos de malformação, sendo um decorrente de aborto. No G4, uma ovelha abortou e as outras três pariram quatro fetos malformados. As principais malformações encontradas no trabalho foram artrogripose, palatosquise, queilosquise, hipoplasia da mandíbula, aplasia do osso incisivo, malformações de olho e língua, polidactilia e monodactilia. Nos grupos de maior percentual de ingestão da planta foram observadas maiores quantidades de malformações e chamou a atenção a ocorrência de retenção de placenta e a alta frequência de mortalidade perinatal nos cordeiros que apresentaram algum tipo de malformação. Demonstrou-se com esse trabalho que a P. pyramidalis é uma importante causa de malformação congênita, aborto e mortalidade perinatal em ovinos, sendo de extrema importância que se mantenha as ovelhas prenhes fora do alcance desta planta durante todo o período gestacional.(AU)

Poincianella pyramidalis (catingueira) is a toxic plant associated with abortions, embryonic losses and malformations in goats and laboratory animals. Outbreaks and sporadic cases of spontaneous intoxication in sheep have been reported in the last five years in the agreste of Pernambuco. Due to the occurrence of these spontaneous cases and the lack of researches in sheep, an experimental study was carried out to evaluate the teratogenic effects of P. pyramidalis on sheep. In the experiment, 16 female and three male sheeps, mixed breed, were used. Females were divided in four groups, with four animals per group and maintained in individual stalls, underwent estrus synchronization and mating by natural mating and after 30 days the diagnosis was made to confirm gestation. Groups were named group 1 (G1), group 2 (G2), group 3 (G3), and group 4 (G4). In G1 (control) the ewes were fed with 1% of concentrate supplementation (CS) based on live weight (LW) and 2% of maize silage (MS) with a daily intake of 3% dry matter (DM) based on LW. In G2 feeding was constituted of 1% of CS based on LW and 2% of forage, including 2% of roughage, 50% was hay of P. pyramidalis and the other 50% of DM. In G3 feed was constituted of 1% of CS based on LW and 2% of roughage. Among these 2% of roughage, 80% was hay of P. pyramidalis and the other 20% of DM. In G4 the sheep were fed with 1% CS based on the LW and the roughage consisting of 100% P. pyramidalis hay. All groups received CS with corn meal, cottonseed meal, mineral salt specific for sheep and water ad libitum. Animals were monthly submitted to ultrasonography to detect embryonic or fetal losses. Serological tests were performed for Neospora caninum and Toxoplasma gondii before introduction of the animals in the experiment. Fetuses with malformations were evaluated in the Laboratory of Animal Anatomy and Pathology of the Academic Unit of Garanhuns (UAG), UFRPE, to describe the lesions. In G2, there were five cases of malformations of eight born lambs. In G3, there were four cases of malformation, one due to abortion. In G4, one sheep aborted and the other three gave birth to four malformed fetuses. Main malformations found in the study were arthrogryposis, palatoschisis, chylosquisis, hypoplasia of the mandible, aplasia of the incisive bone, malformations of the eye and tongue, polidactyly and monodactyly. In the groups with higher doses, larger numbers of malformations were observed, and the occurrence of placental retention and the high frequency of perinatal mortality in lambs presenting some type of malformation were noted. It has been demonstrated that P. pyramidalis is an important cause of congenital malformation, abortion and perinatal mortality in sheep, therefore keeping pregnant sheep away from this plant throughout the gestation period is utmost important.(AU)

Reproductive losses caused by the ingestion of Poincianella pyramidalis in sheep.

Malformations have been observed in sheep and goats in the Brazilian semiarid region in areas where Poincianella pyramidalis is dominant. The objective of this trial was to determine whether Poincianella pyramidalis causes reproductive changes in pregnant sheep. Sixteen non-pregnant sheep were mated with two rams. After confirmation of the pregnancy by ultrasonography on the 18th day after mating, pregnant sheep were randomly divided into four groups (#1, 2, 3, and 4), with four animals each. Sheep received roughage in an amount equivalent to 2% of their body weight, mixed with 0%, 10%, 20% and 40% of dried leaves of P. pyramidalis for groups 1, 2, 3 and 4, respectively. In Groups 1 and 2, all animals lambed normally. In Group 3 (20% P. pyramidalis in the roughage), one lamb was born with arthrogryposis and three sheep gave birth to premature weak lambs within 128, 132, and 133 days of gestation. In Group 4 (40% P. pyramidalis in the roughage), one sheep lambed a normal lamb; another ewe had embryonic mortality after seven days of plant consumption, and two aborted on days 103 and 144 of pregnancy. One of the aborted fetuses was normal and the other showed arthrogryposis and prognathism. These results suggest that P. pyramidalis causes embryonic deaths, abortions, and malformations in sheep. Grazing pregnant sheep in areas where this plant is dominant should be avoided, and roughage for confined pregnant females should not contain more than 10% P. pyramidalis.

Acute and chronic toxicity and antimicrobial activity of the extract of Stryphnodendron adstringens (Mart) Coville / Toxicidade aguda e crônica e atividade antimicrobiana do extrato de Stryphnodendron adstringens (Mart) Coville

This study evaluated the antimicrobial activity and acute or chronic toxicity of the extract of Stryphnodendron adstringens. The stem bark dry extract was obtained by static maceration with ethanol. Quantification of tannins was performed by the Folin-Denis method, which indicated a total tannin content of 32.7%. The antimicrobial activity of the dry extract of S. adstringens was evaluated by agar-based disk diffusion assay with Escherichia coli (ATCC 25922) and Staphylococcus aureus (ATCC 25923) in the concentration of 200, 400 and 600µL/mL. The results indicated that 600µL/mL inhibited microbial growth, i.e. had antimicrobial activity against these species. Acute and chronic toxic effects of S. adstringens was evaluated in Wistar rats treated with 200, 400, 600 and 800mg/kg of extract, administrated by gavage. Liver degeneration was observed in the group of rats receiving 800mg/kg in chronic exposure, what may indicate some degree of toxicity at this concentration. However, no systemic toxicity was observed at lower doses. Considering the broad use of S. adstringens as a phytotherapeutic agent for various human and animal diseases and the livertoxicity observed at high concentrations, attention should be paid to the possible adverse effect of using the extract from this plant at high concentration.(AU)

Avaliou-se neste estudo a atividade antimicrobiana e a toxicidades aguda e crônica do extrato da entrecasca de Stryphnodendron adstringens. A partir do extrato seco, obtido através da maceração estática da casca do caule em etanol de cereais, foi realizada a quantificação de taninos totais (32,7%) pelo método de Folin-Denis. A atividade antimicrobiana do extrato seco extraído de cascas do caule de S. adstringens foi avaliada pela técnica de disco-difusão para os micro-organismos Escherichia coli (ATCC 25922) e Staphylococcus aureus (ATCC 25923) nas concentrações de 200, 400 e 600µL/mL. Os testes de concentração inibitória mínima revelaram que 600µL/mL inibiu o crescimento dos dois micro-organismos testados; o mesmo resultado foi observado para atividade bactericida na concentração de 600µL/mL sobre essas espécies. Efeitos tóxicos sistêmicos agudos e crônicos do extrato seco de S. adstringens administrados por gavagem foram estudados em ratos Wistar, utilizando as doses de 400, 600 e 800mg/kg. Foi observada degeneração hepática no grupo de animais que receberam 800mg/kg tanto no estudo da toxicidade aguda quanto crônica, que pode indicar algum grau de toxicidade de S. adstringens nessa concentração. Considerando o amplo uso de S. adstringens como fitoterápico para humanos e animais, atenção deve ser dispensada para ingestão em altas doses mediante os efeitos tóxicos observados neste estudo.(AU)

Intoxicação natural e experimental por Leucaena leucocephala em equinos / Natural and experimental Leucaena leucocephala poisoning in horses

Este trabalho investigou as principais alterações clínicas e dermatopatológicas de equinos intoxicados natural e experimentalmente por Leucaena leucocephala. Os surtos ocorreram nos estados de São Paulo e Goiás, onde seis cavalos após a ingestão de casca e/ou folhas de L. leucocephala apresentaram alopecia, principalmente na crina e cauda. Nesses animais o diagnóstico foi baseado na observação da ingestão da planta e dos sinais clínicos. Nos animais intoxicados experimentalmente, foi realizado o exame clínico, biópsias da pele das regiões de crina, dorso e cauda e foi feita dosagem sérica de tri-iodotironina (T3) e tiroxina (T4). Alopecia da crina e cauda foi o principal sinal clínico observado, seguido de anorexia, emagrecimento e apatia em todos os equinos. Os níveis de T3 e T4 total apresentaram redução significativa (p≤0,05) na terceira semana de ingestão da leucena quando comparado aos níveis basais. As alterações histológicas observadas nas biópsias de pele demonstram acentuada telogenização dos folículos pilosos ao final dos experimentos. Os achados clínico-patológicos em equinos intoxicados são semelhantes aos observados em ruminantes. A intoxicação experimental de equinos por L. leucocephala evidenciou o acentuado declínio dos níveis dos hormônios tireoideanos, sugerindo efeito bociogênico da mimosina e seus compostos derivados, com hipotireoidismo transitório e alopecia devido à acentuada redução da atividade folicular.(AU)

This paper reports the main clinical changes of natural and experimentally poisoning by Leucaena leucocephala in horses. Outbreaks of poisoning occurred in São Paulo and Goiás States, where six horses after ingestion of bark and/or leaves of the plant showed alopecia mainly in mane and tail. The diagnosis was based on the observation of plant intake and clinical signs. In horses experimentally poisoned, clinical examination was performed and skin biopsies were taken from mane, back and tail regions, and triiodothyronine (T3) and thyroxine (T4) serum levels were assayed. Alopecia in mane and tail was the main clinical sign, accompanied by anorexia, weight loss and lethargy in all horses. T3 and total T4 showed significant decrease in serum levels (p≤0.05) in the third week of leucaena intake compared with baseline levels. Marked telogenization of hair follicles at the end of the experiments were observed in skin biopsies. The clinical and pathological findings in poisoned horses are similar to those observed in ruminants. Experimental poisoning of horses by the plant highlights the marked decline in levels of thyroid hormones, suggesting goitrogenic effect of mimosine and its derived compounds, with transient hypothyroidism and alopecia due to accentuated reduction in follicular activity.(AU)

Acute and chronic toxicity and antimicrobial activity of the extract of Stryphnodendron adstringens (Mart) Coville / Toxicidade aguda e crônica e atividade antimicrobiana do extrato de Stryphnodendron adstringens (Mart) Coville

This study evaluated the antimicrobial activity and acute or chronic toxicity of the extract of Stryphnodendron adstringens. The stem bark dry extract was obtained by static maceration with ethanol. Quantification of tannins was performed by the Folin-Denis method, which indicated a total tannin content of 32.7%. The antimicrobial activity of the dry extract of S. adstringens was evaluated by agar-based disk diffusion assay with Escherichia coli (ATCC 25922) and Staphylococcus aureus (ATCC 25923) in the concentration of 200, 400 and 600µL/mL. The results indicated that 600µL/mL inhibited microbial growth, i.e. had antimicrobial activity against these species. Acute and chronic toxic effects of S. adstringens was evaluated in Wistar rats treated with 200, 400, 600 and 800mg/kg of extract, administrated by gavage. Liver degeneration was observed in the group of rats receiving 800mg/kg in chronic exposure, what may indicate some degree of toxicity at this concentration. However, no systemic toxicity was observed at lower doses. Considering the broad use of S. adstringens as a phytotherapeutic agent for various human and animal diseases and the livertoxicity observed at high concentrations, attention should be paid to the possible adverse effect of using the extract from this plant at high concentration.(AU)

Avaliou-se neste estudo a atividade antimicrobiana e a toxicidades aguda e crônica do extrato da entrecasca de Stryphnodendron adstringens. A partir do extrato seco, obtido através da maceração estática da casca do caule em etanol de cereais, foi realizada a quantificação de taninos totais (32,7%) pelo método de Folin-Denis. A atividade antimicrobiana do extrato seco extraído de cascas do caule de S. adstringens foi avaliada pela técnica de disco-difusão para os micro-organismos Escherichia coli (ATCC 25922) e Staphylococcus aureus (ATCC 25923) nas concentrações de 200, 400 e 600µL/mL. Os testes de concentração inibitória mínima revelaram que 600µL/mL inibiu o crescimento dos dois micro-organismos testados; o mesmo resultado foi observado para atividade bactericida na concentração de 600µL/mL sobre essas espécies. Efeitos tóxicos sistêmicos agudos e crônicos do extrato seco de S. adstringens administrados por gavagem foram estudados em ratos Wistar, utilizando as doses de 400, 600 e 800mg/kg. Foi observada degeneração hepática no grupo de animais que receberam 800mg/kg tanto no estudo da toxicidade aguda quanto crônica, que pode indicar algum grau de toxicidade de S. adstringens nessa concentração. Considerando o amplo uso de S. adstringens como fitoterápico para humanos e animais, atenção deve ser dispensada para ingestão em altas doses mediante os efeitos tóxicos observados neste estudo.(AU)

Intoxicação natural e experimental por Leucaena leucocephala em equinos / Natural and experimental Leucaena leucocephala poisoning in horses

Este trabalho investigou as principais alterações clínicas e dermatopatológicas de equinos intoxicados natural e experimentalmente por Leucaena leucocephala. Os surtos ocorreram nos estados de São Paulo e Goiás, onde seis cavalos após a ingestão de casca e/ou folhas de L. leucocephala apresentaram alopecia, principalmente na crina e cauda. Nesses animais o diagnóstico foi baseado na observação da ingestão da planta e dos sinais clínicos. Nos animais intoxicados experimentalmente, foi realizado o exame clínico, biópsias da pele das regiões de crina, dorso e cauda e foi feita dosagem sérica de tri-iodotironina (T3) e tiroxina (T4). Alopecia da crina e cauda foi o principal sinal clínico observado, seguido de anorexia, emagrecimento e apatia em todos os equinos. Os níveis de T3 e T4 total apresentaram redução significativa (p≤0,05) na terceira semana de ingestão da leucena quando comparado aos níveis basais. As alterações histológicas observadas nas biópsias de pele demonstram acentuada telogenização dos folículos pilosos ao final dos experimentos. Os achados clínico-patológicos em equinos intoxicados são semelhantes aos observados em ruminantes. A intoxicação experimental de equinos por L. leucocephala evidenciou o acentuado declínio dos níveis dos hormônios tireoideanos, sugerindo efeito bociogênico da mimosina e seus compostos derivados, com hipotireoidismo transitório e alopecia devido à acentuada redução da atividade folicular.(AU)

This paper reports the main clinical changes of natural and experimentally poisoning by Leucaena leucocephala in horses. Outbreaks of poisoning occurred in São Paulo and Goiás States, where six horses after ingestion of bark and/or leaves of the plant showed alopecia mainly in mane and tail. The diagnosis was based on the observation of plant intake and clinical signs. In horses experimentally poisoned, clinical examination was performed and skin biopsies were taken from mane, back and tail regions, and triiodothyronine (T3) and thyroxine (T4) serum levels were assayed. Alopecia in mane and tail was the main clinical sign, accompanied by anorexia, weight loss and lethargy in all horses. T3 and total T4 showed significant decrease in serum levels (p≤0.05) in the third week of leucaena intake compared with baseline levels. Marked telogenization of hair follicles at the end of the experiments were observed in skin biopsies. The clinical and pathological findings in poisoned horses are similar to those observed in ruminants. Experimental poisoning of horses by the plant highlights the marked decline in levels of thyroid hormones, suggesting goitrogenic effect of mimosine and its derived compounds, with transient hypothyroidism and alopecia due to accentuated reduction in follicular activity.(AU)