Anti-Toxoplasma gondii and anti-Neospora caninum antibodies in dogs with and without neurological signs / Anticorpos anti-Toxoplasma gondii e anti-Neospora caninum em cães com e sem sinais neurológicos

This study investigated the association between neurological signs as well as plausible risk factors and the seroprevalence of Toxoplasma gondii and Neospora caninum infection in dogs of the Campo Grande region of Mato Grosso do Sul, Brazil. In this study, the dogs were divided into two groups based on the presence and the absence of neurological signs (n=30 in each group). Serological diagnosis was performed using the indirect fluorescent antibody test. In the group with neurological disorders, 23.3% and 30% of the dogs had anti-T. gondii and anti-N. caninum antibodies, respectively. Moreover, three dogs from this group showed co-infection with both protozoa. In the group without neurological signs, 16.7% and 13.3% of the dogs were seropositive for T. gondii and N. caninum, respectively. Although presence of neurological signs was not associated with T. gondii and N. caninum infections (P = 0.747 and P = 0.21, respectively), there was a statistical association between T. gondii seropositivity and peripheral neurological alteration (P = 0.016) among dogs with neurological signs. Raw meat ingestion was the only risk factor associated with the presence of anti-N. caninum antibodies (P = 0.041). Results revealed evidence of exposure to N. caninum and T. gondii in dogs irrespective of the presence of neurological signs. Moreover, this study highlighted the need for serological investigation of T. gondii in dogs with disturbances in peripheral nervous systems and not offering raw meat to animals to avoid the risk of N. caninum infection.

Este estudo teve como objetivo investigar a associação entre sinais neurológicos, assim como possíveis fatores de risco e soroprevalência de Toxoplasma gondii e Neospora caninum em cães de Campo Grande, região de Mato Grosso do Sul, Brasil. Nesse estudo, os cães foram divididos em dois grupos, baseado na presença ou ausência de sinais neurológicos (n = 30 em cada grupo). O diagnóstico sorológico foi realizado por meio do teste imunofluorescência indireta (RIFI). No grupo com distúrbios neurológicos, 23.3% e 30% dos cães tinham anticorpos anti-T. gondii e anti-N. caninum, respectivamente. Além disso, três cães deste grupo estavam coinfectados com ambos os protozoários. No grupo sem sinais neurológicos, 16.7% e 13.3% dos cães foram soropositivos para T. gondii e N. caninum, respectivamente. Apesar da presença de sinais neurológicos não ter sido associado a infecção por T. gondii ou N. caninum ( P = 0.747 e P = 0.21, respectivamente), houve associação estatística entre soropositividade para T. gondii e alteração neurológica periférica (P = 0.016) entre os cães com sinais neurológicos. A ingestão de carne crua foi o único fator de risco que apresentou associação com a presença de anticorpos para N. caninum (P = 0.041). Estes resultados mostraram evidência de que a exposição a N. caninum e T. gondii em cães independe da presença de sinais neurológicos. Além disso, este estudo destaca a necessidade de investigação sorológica para T. gondii em cães com distúrbios neurológicos periféricos, e o oferecimento de carne crua aos animais deve ser evitada devido ao risco de infecção por neosporose.

Lafora's disease in a free-ranging toco toucan (Ramphastos toco) with neurologic disease

Lafora's disease is a genetic disease associated to mutations in genes that encodes laforin and malin, which results in intracellular polyglucan storage. The present report describes a case of Lafora's disease in a toco toucan with episodes of incoordination and myoclonus that resulted in traumatic lesions and fracture of the left hindlimb. The bird was euthanized and submitted to necropsy. Microscopically there were abundant PAS-positive and diastasis-resistant Lafora's inclusion bodies in neurons in the cerebellum, supporting the diagnosis of Lafora's disease.(AU)

Potential of marine compounds in the treatment of neurodegenerative diseases: a review / Potencial de compostos marinhos no tratamento de doenças neurodegenerativas: uma revisão

Neurodegenerative diseases (ND) are characterized, especially, by the progressive loss of neurons, resulting in neuropsychomotor dysfunctions. Even with a high prevalence, NDs are treated with drugs that alleviate the symptoms of patients, but which develop adverse events and still do not inhibit the progression of the disease. Thus, within a new pharmacological perspective, this review aimed to verify the therapeutic potential of natural compounds of marine origin against ND. For this, an integrative review was carried out, according to the PRISMA methodology, which included steps such as: search, pre-selection and inclusion of articles. The results described revealed species such as Acaudina malpodioides, Holothuria scabra and Xylaria sp., which presented important evidence in relation to Alzheimer's, reducing the generation of ROS, presenting neuroprotective effects and reducing the concentration of Aß peptide. Regarding Parkinson's disease (PD), another example of ND, the bioactive compounds from Holothuria scabra and Xylaria sp., showed to be able to reduce the degeneration of dopaminergic neurons, reduce the deposition of alpha synuclein and reduce the formation of Mutant Huntingtin protein (Mhtt). The other marine compounds and bioactive substances are also described in this review. In conclusion, the evaluated studies indicate that compounds of marine origin emerge as a promising source of bioactive compounds, revealing an important therapeutic potential for the treatment of ND.

As doenças neurodegenerativas (ND) são caracterizadas, especialmente, pela perda progressiva de neurônios, resultando em disfunções neuropsicomotoras. Mesmo apresentando uma alta prevalência, as DN são tratadas com medicamentos que aliviam os sintomas dos pacientes, mas que desenvolvem eventos adversos e ainda não inibem a progressão da doença. Assim, dentro de uma nova perspectiva farmacológica, esta revisão teve como objetivo verificar o potencial terapêutico de compostos naturais de origem marinha frente às DN. Para tal, foi realizada uma revisão integrativa, segundo a metodologia PRISMA que compreendeu etapas como: busca, pré-seleção e inclusão dos artigos. Os resultados descritos revelaram espécies como, Acaudina malpodioides, Holothuria scabra e Xylaria sp., que apresentaram importantes evidências em relação ao Alzheimer, reduzindo a geração de ROS, apresentando efeitos neuroprotetores e reduzindo a concentração de peptídeo Aß. Sobre a doença de Parkinson (PD), outro exemplo de ND, os compostos bioativos da Holothuria scabra e da Xylaria sp., mostraram ser capazes de diminuir a degeneração de neurônios dopaminérgicos, reduzir a deposição de alfa sinucleína e reduzir a formação de agregados da proteína Huntingtina mutante (Mhtt). Os outros compostos marinhos e substâncias bioativas também são descritos nesta revisão. Em conclusão, os estudos avaliados indicam que os compostos de origem marinha despontam como uma promissora fonte de compostos bioativos, revelando um importante potencial terapêutico para o tratamento das ND.

Physiological gait test: an effective method for analyzing balance, locomotion, and neuromuscular disorders in rats and a comparison to the elevated beam test / Teste de marcha fisiológica: um método eficaz para analisar distúrbios de equilíbrio, locomoção e neuromusculares em roedores

The evaluation of animal locomotor activity is a behavioral tool widely used to measure the mechanisms underlying a particular disease, disorder, or injury, as well as the effects of exposure to a xenobiotic. The elevated beam test is one of the most used tests in rodents to assess balance and motor coordination. Despite being inexpensive and utilizing a simple apparatus, the high beam test requires a long period of animal training and habituation. The development and characterization of an alternative test, namely the gait test, has the potential to circumvent the time and effort required for animal training, deeming it an effective, inexpensive, and fast method for the analysis of behaviors that are comparably assessed by the high beam test. Therefore, the present study focused on determining the effectiveness and feasibility of the gait test for assessing rodent locomotion and balance as a replacement for the elevated beam test. For this purpose, male rats were divided into three groups: one control group exposed to a saline solution (NaCl 0.9%) and two experimental groups exposed to a single dose of either 0.2 or 1.0 mg/kg of ivermectin intraperitoneally for induction of locomotor disturbance. The high beam and gait tests were performed 15 min and 24 h after drug administration. Results show that the experimental groups had difficulty performing the tasks of either test at both time points analyzed compared to the control groups. At the high beam, experimental animals had trouble maintaining balance and walking. At the gait test, experimental animals showed alterations in gait, which were quantitated by: (a) shortening of step length, (b) decrease of stride, (c) altered step symmetry, and (d) altered stride area. Such results are indicative of compensatory efforts and were comparable between both tests. Altogether, the data indicate that the gait test meets all requirements for assessing motor coordination in rodents. The gait test is therefore validated as a complement to the elevated beam test for the study and analysis of neurodegenerative impairment and other disorders involving neuromuscular disturbances.(AU)

A avaliação da atividade locomotora animal é uma ferramenta comportamental bastante utilizada para mensurar os mecanismos subjacentes a uma determinada doença, distúrbio ou lesão e efeitos da exposição a um xenobiótico. Um dos testes mais utilizados em roedores para avaliar o equilíbrio e coordenação motora é o teste da trave elevada que, apesar de ser um teste barato e que exige um aparato simples, é necessário um longo período de treino e habituação dos animais. O desenvolvimento e caracterização de um teste alternativo, chamado de teste da marcha, tem o potencial de contornar o tempo e o esforço necessários ao treino dos animais, considerando-o um método eficaz, barato e rápido para a análise de comportamentos avaliados comparativamente pelo alto teste de feixe. Portanto, o presente estudo concentrou-se em determinar a eficácia e viabilidade do teste de marcha para avaliação da locomoção e equilíbrio de roedores em substituição ao teste da trave elevada. Para isso, ratos machos foram divididos em 3 grupos, sendo 1 grupo controle exposto à solução salina (NaCl 0,9%) e 2 grupos experimentais expostos à dose única de 0,2 e 1,0 mg/kg de ivermectina por via intraperitoneal para indução da alteração locomotora. Os testes de trave elevada e marcha foram realizados 15 min e 24 h após a administração da droga. Os resultados mostram que os grupos experimentais tiveram dificuldade em realizar as tarefas de qualquer teste em ambos os momentos analisados em comparação com os grupos de controle. Na trave elevada, os animais experimentais tiveram dificuldade em manter o equilíbrio e andar. No teste de marcha, os animais experimentais apresentaram alterações na marcha, que foram quantificadas por: (a) encurtamento do comprimento da passada, (b) diminuição da passada, (c) alteração da simetria da passada e (d) alteração da área da passada. Tais resultados são indicativos de esforços compensatórios e foram comparáveis entre os dois testes. Em conjunto, os dados indicam que o teste de marcha atende a todos os requisitos para avaliação da coordenação motora em roedores. O teste de marcha é, portanto, validado como um complementar para o teste da trave elevada e para o estudo e análise de comprometimento neurodegenerativo e outros distúrbios envolvendo distúrbios neuromusculares.(AU)

Neurological diseases of viral origin in cattle in the state of Pernambuco, Brazil: clinical and anatomopathological study / Enfermidades neurológicas de origem viral em bovinos no estado de Pernambuco, Brasil: estudo clínico e anatomopatológico

Studies related to neurological diseases are of great importance in Veterinary Medicine, particularly those involving production animals, such as cattle, due to their wide sanitary and public health significance. Therefore, the current study aims to describe the frequency of occurrence of the main clinical, laboratory, and anatomopathological findings of cattle diagnosed with neurological diseases of viral origin. Screening was performed in the general register of patients diagnosed through anatomopathological and/or complementary examination with illnesses of viral origin, admitted (live or dead) to the Clínica de Bovinos de Garanhuns-UFRPE from January 2009 to December 2019. The information recovered was entered in a database created in the computer program Microsoft Excel 2010®, distributed into clinical, laboratory, and anatomopathological data. The clinical findings on neurological diseases of viral etiology were very varied and non-specific, and the anatomopathological findings, together with laboratory methods, were of fundamental importance for the establishment of the diagnosis. The high frequency of rabies cases in this study demonstrates the importance of this disease for cattle rearing, as well as for Public Health. We emphasize the importance of including malignant catarrhal fever and herpes meningoencephalitis in the differential diagnosis of neurological diseases in the region, as well as the adoption of sanitary measures.

Os estudos relacionados as doenças neurológicas assumem grande importância na Medicina Veterinária, particularmente os que envolvem animais de produção como os bovinos, em virtude da grande importância sanitária e de saúde pública. Nesse contexto, este trabalho teve como objetivo descrever a frequência de ocorrência dos principais achados clínicos, laboratoriais e anatomopatológicos dos bovinos diagnosticados com doenças neurológicas de origem viral. Realizou-se a triagem no livro de registro geral dos pacientes com enfermidades que cursaram com sintomatologia neurológica e que foram diagnosticados através de exame anatomopatológico e/ou complementares com enfermidades de origem viral, os quais deram entrada (vivos ou mortos) na Clínica de Bovinos de Garanhuns-UFRPE no período de janeiro de 2009 a dezembro de 2019. As informações obtidas foram inseridas em um banco de dados elaborado no programa de computador Microsoft Excel 2010® distribuídas em dados clínicos, laboratoriais e anatomopatológicos. Os achados clínicos das enfermidades neurológicas de etiologia viral foram muito variados e inespecíficos, sendo os achados anatomopatológicos, aliados aos métodos laboratoriais, de importância fundamental para o estabelecimento do diagnóstico. A elevada frequência dos casos de raiva neste estudo demonstra a importância sanitária desta enfermidade para a pecuária bovina, como também para a saúde pública. Ressalta-se a importância da inclusão da febre catarral maligna e da meningoencefalite herpética no diagnóstico diferencial das doenças neurológicas na região, assim como a adoção de medidas sanitárias.

Equine herpesvirus myeloencephalopathy

Clinical History: A euthanized, 14-year-old, Warmblood gelding that had participated in an equine show was presented for necropsy and diagnostic workup to the San Bernardino laboratory of the California Animal Health and Food Safety Laboratory System. The animal had a 4-day history of mildly swollen limbs and hyperthermia, and developed neurologic signs shortly before euthanasia. Necropsy Findings: The urinary bladder had multifocal to coalescing hemorrhages in the mucosa and approximately 5 ml of turbid urine with sandy sludge (Figure 1). The entire spinal cord was removed and cross-sectioned serially after fixation in 10% neutral-buffered formalin during 48h. Multifocally, in multiple sections of the cervical, thoracic, and lumbar segments, there were uni- or bilateral and asymmetrical, wedge-shaped areas of gray discoloration and hemorrhage (Figures 2-4). In addition, there were extensive hemorrhages around the nerve roots of the cauda equina. Follow-up questions: Five differential diagnoses for the gross lesions in the spinal cord (Fig. 1B-1D) Microscopic description for the lesions in the spinal cord (Fig. 2A-2D) Most likely cause based on clinical history and gross and microscopic findings.

Polineuropatia motora em cão adulto / Motor polyneuropathy in an adult dog

Background: Nonambulatory flaccid tetraparesis can be the result of diseases of the peripheral nervous system and it is characterized by generalized lower motor neuron (LMN) signs, as weakness, tetraparesis/tetraplegia, decreased muscle tone and reflexes. The term polyneuropathy is used for dysfunction of multiple peripheral nerves. In Brazil, there are several etiologies for polyneuropathy in dogs, such as acute idiopathic polyradiculoneuritis, botulism and myasthenia gravis. Toxoplasma gondii is an uncommon cause of LMN diseases in dogs. The aim of this report was to describe a case of flaccid tetraplegia toxoplasmosis in an adult dog with a Toxoplasma gondii serology with a markedly elevated IgG titer of 1:4096. Case: A 4-year-old intact mongrel male dog, weighing 19.6 kg, was referred to the Veterinary Medical Teaching Hospital of the Universidade Estadual de Londrina (UEL) with a 5-day history of weakness that progressed to tetraparesis. Physical examination revealed no significant changes other than the dull and unkempt coat. Neurologic examination revealed severe tetraparesis that was worse in the pelvic limbs, with decreased muscle tone in all four limbs. Postural reactions and the interdigital reflex were absent in all four limbs, as was the patellar reflex, but pain perception was present. There were no clinical signs of dysfunction on examination of the cranial nerves. Laboratory tests were performed, and creatine kinase was elevated (819 U/L). Blood was drawn to look for antibodies to Toxoplasma gondii and Neospora caninum class IgG using the indirect immunofluorescence technique. The antibody titer for Toxoplasma gondii (IgG) was 1:4096. A chest radiograph was performed to look for megaesophagus, and a pulmonary pattern suggestive of mild diffuse pneumonia was observed. Treatment was performed with sulfamethoxazole and trimethoprim, and the dog's condition improved slightly. Discussion: Based on lower motor neuron findings, the neurologic lesion was localized in the nerve roots, peripheral nerves, neuromuscular junctions, or muscles. The most important diseases in the list of differential diagnoses were immune-mediated or infectious polyradiculoneuritis (toxoplasmosis, neosporosis), myasthenia gravis, toxic polyneuropathy (botulism, chronic organophosphate poisoning), and paraneoplastic polyneuropathy. Among these differential diagnoses, polyradiculoneuritis is one of the most common. It is an idiopathic inflammatory disease. Exposure to raccoon saliva (in the U.S.), vaccination, or infection have been proposed as precipitating causes, but the triggers of this disease remain unknown. Serology for neosporosis was negative, while IgG titers for toxoplasmosis were 1:4096. In a previous study, dogs with acute polyradiculoneuritis were more likely to have T. gondii IgG serum antibody titers than dogs without neurologic signs. Infection with the protozoa T. gondii and N. caninum can cause intense polyradiculoneuritis in dogs accompanied by myositis, especially in puppies. One treatment trial was based on the administration of sulfonamide-trimethoprim with pyrimethamine, whose efficacy in the treatment of toxoplasmosis in dogs has also been reported in the literature. Neurologic deficits improved slightly, and there is a possibility that certain signs may not disappear completely because of the permanent damage caused by inflammation of the nervous system, as observed in the present case. The case had the limitation that it was not possible to perform other laboratory tests to demonstrate histopathologically the presence of Toxoplasma gondii organisms in muscles or nerves. Recovery of normal function is less likely in protozoan polyradiculoneuritis than in noninfectious polyradiculoneuritis. Thus, in the present case, the main suspicion was polyradiculoneuritis secondary to toxoplasmosis. Although it is a rare condition, it is important to consider toxoplasmosis in dogs with LMN-type tetraparesis or tetraplegia.

Descriptive cross-sectional study on major bovine diseases and associated risk factors in north-eastern Ecuadorian Amazon / Estudo transversal descritivo sobre as principais doenças bovinas e fatores de risco associados no nordeste da Amazônia equatoriana

Cattle raising is a crucial element of production systems in the tropics and subtropics. However, in recent years, global public health security has been threatened by disease emergence. In Orellana Province, livestock is the most important activity to generate economic income. Nevertheless, there is no available data about Animal Health status. With this objective, a study was performed to describe the major Bovine diseases recorded between 2011 to 2019, and the main Risk factors associated. Data on main Bovine diseases were retrieved from the World Animal Health Information System database. Whereas Bovine population data used to calculate the prevalence rates and confidence intervals were obtained from Ecuador's Ministry of Agriculture. By contrast, the Risk factors identified with an epidemiological questionnaire were applied to 300 livestock farmers. As a result, from 2011 to 2019 in Orellana has been confirmed: 90 cases of Infectious Bovine Rhinotracheitis (31.58%), Bovine Rabies by hematophagous bats (Desmodus rotundus), 83 cases (29.12%), Bovine viral diarrhea with 43 cases (15.10%), Brucellosis by Brucella abortus 35 cases, which was (12.28%), and 34 cases related to Enzootic bovine leukosis (11.92%). Overall, the prevalence rates ranged from (0.24 to 15.37%). In addition, farm size, presence of forest, herd, and paddock sizes, cutting frequency of forages, and other animal species were involved as Risk factors (OR = 3.15 to 11.75; 95% CI, 0.01 to 0.69). In conclusion, there are animal diseases with reproductive and neurologic symptomology and high-Risk factors implicated in the transmission. Consequently, space-temporal and seroprevalence epidemiological studies should be performed in Orellana.

A criação de gado é um elemento crucial dos sistemas de produção nos trópicos e subtrópicos. No entanto, nos últimos anos, a segurança da saúde pública global tem sido ameaçada pelo surgimento de doenças. Na província de Orellana, a pecuária é a atividade mais importante para gerar renda econômica. Contudo, não há dados disponíveis sobre o estado de saúde animal. Com este objetivo, foi realizado um estudo para descrever as principais doenças dos bovinos registradas entre 2011 e 2019, além dos principais fatores de risco associados. Os dados sobre as principais doenças bovinas foram recuperados do banco de dados do World Animal Health Information System. Os dados da população bovina usados para calcular as taxas de prevalência e os intervalos de confiança foram obtidos do Ministério da Agricultura do Equador. Por outro lado, os fatores de risco identificados com um questionário epidemiológico foram aplicados a 300 criadores de gado. Como resultado, de 2011 a 2019 em Orellana foram confirmados: 90 casos (31,58%) de rinotraqueíte infecciosa bovina, 83 casos (29,12%) de raiva bovina por morcegos hematófagos (Desmodus rotundus), 43 casos (15,10%) de diarreia viral bovina, 35 casos (12,28%) de brucelose por Brucella abortus e 34 casos relacionados à leucose enzoótica bovina (11,92%). No geral, as taxas de prevalência variaram de 0,24 a 15,37%. Além disso, tamanho da fazenda, presença de floresta, tamanho do rebanho e dos piquetes, frequência de corte de forragens e outras espécies animais estiveram envolvidos como fatores de risco (OR = 3,15-11,75; IC 95% 0,01-0,69). Em conclusão, existem doenças animais com sintomatologia reprodutiva e neurológica e fatores de alto risco implicados na transmissão. Portanto, estudos epidemiológicos espaço-temporais e de soroprevalência devem ser realizados em Orellana.

Prevalence and clinical features of neurological disorders in dogs attended at Federal Rural University of Rio de Janeiro (2017-2018) / Caracterização clínica dos distúrbios neurológicos observados em cães atendidos na Universidade Federal Rural do Rio de Janeiro (2017-2018)

Neurological disorders are frequent in small animal veterinary clinics and studies giving regional justification for such disorders are essential so that veterinarians can be better prepared. The objective of this retrospective study was to describe the clinical and epidemiological aspects of dogs with neurological disorders treated at the Veterinary Hospital of Federal Rural University of Rio de Janeiro, between August 2017 and April 2018. The study describes the location of the lesions and their etiology according to the acronym VITAMIN-D, as well as the distribution of cases according to sex, breed and age. One hundred and twenty-two (122) dogs were included, of which 58% (n=71) were males and 42% (n=51) females. The age distribution ranged from two months to 18 years old; 16% were less than two years old, 50% between two and seven years old and 34% were more than seven years old. The most affected breeds were Mixed Breed dogs (43%), Poodles (9%) and Dachshunds (7%). The diagnoses were confirmed in 54 animals (44%) and in 68 (56%) remained presumptive. The most common location was the spinal cord (61%), where the T3-L3 region was the most affected (35%), followed by multifocal (20%) and forebrain (10%). The most frequent categories were degenerative (24%), inflammatory/infectious (23%) and traumatic (20%) diseases. Intervertebral disc disease was the most observed, corresponding to 21.3% of all cases. The results showed that the neurological diseases in this Veterinary Hospital were more prevalent in young male adults with spinal cord diseases of degenerative nature.(AU)

Desordens neurológicas são frequentes na clínica de pequenos animais. Estudos caracterizando a casuística regio-nal são fundamentais para melhor instrução e preparo técnico do médico veterinário. O objetivo deste trabalho retrospectivo foi descrever os aspectos clínicos e epidemiológicos de cães com distúrbios neurológicos atendidos no Hospital Veterinário da Universidade Federal Rural do Rio de Janeiro, entre agosto de 2017 e abril de 2018, caracterizando a localização da lesão e etiologia de acordo com o acrônimo VITAMINA-D, bem como a distribuição dos casos em relação ao sexo, raça e faixa etária. Foram incluídos 122 cães, com 58% (n=71) dos casos em machos e 42% (n=51) em fêmeas. A distribuição etária variou de dois meses a 18 anos, sendo 16% dos animais menores de dois anos, 50% entre dois e sete anos e 34% maiores de sete anos. As raças mais observadas foram SRD (43%), Poodle (9%) e Dachshund (7%). O diagnóstico etiológico foi confirmado em 54 animais (44%) e em 68 (56%) permaneceu como presuntivo. A localização mais comum foi na medula espinhal (61%), sendo a região entre T3-L3 a mais acometida (35%), seguida por multifocal (20%) e prosencéfalo (10%). As categorias mais frequentes foram de doenças degenerativas (24%), inflamatórias/infecciosas (23%) e traumáticas (20%). Dos cães com doenças degenerativas, a doença do disco intervertebral foi mais observada (21,3% do total dos casos). Com base nos resultados obti-dos, pode-se concluir que, na casuística regional deste Hospital, as doenças neurológicas foram mais prevalentes em machos, adultos jovens e com localização medular de origem degenerativa.(AU)

Polioencephalomalacia in sheep - clinical and magnetic resonance imaging findings

Background: Polioencephalomalacia (PEM) is a neurological disease in ruminants, which is characterized by malacia of brain gray matter. Thiamine deficiency and sulfur intoxication are the most common causes of PEM in sheep. Affected animals present signs of cerebrocortical syndrome, including amaurosis, ataxia, head pressing, mental depression, seizures, and opisthotonus. The neurological examination aims to determine the neurolocalization of the lesions and advanced imaging techniques are useful for confirming the affected area(s) in the central nervous system. The aim of this study is to describe clinical features and ante-mortem diagnosis using magnetic resonance imaging (MRI) in a sheep with PEM. Case: A 18-month-old male Dorper sheep from a flock started receiving concentrate 7 days before. According to the owner, no clinical signs of abnormality were observed on the previous morning. However, in the afternoon, the animal became selfisolated and did not follow the flock to the sheepfold. The following day, he was found in recumbency. Physical examination revealed lateral recumbency, rectal temperature 39.5ºC, 52 bpm, 120 bpm, congested mucous membranes, capillary refill time 1 s, ruminal (4/5 min) and intestinal hypomotility. The assessment of the central nervous system revealed a decreased level of consciousness, focal seizures, opisthotonus, and absence of menace response. The following differential diagnoses were listed: PEM, head trauma, focal symmetrical encephalomalacia, bacterial encephalitis, and rabies. Treatment was composed of dexamethasone [0.2 mg/kg - i.v., SID (1st-3rd day), 0.1 mg/kg, i.v., SID (4th-6th day), and 0.05 mg/kg, i.v., SID (7th-9th day)]; mannitol [1 g/kg - i.v. and diazepam 0.4 mg/kg, i.v. single dose at admission]; vitamin B1 [10 mg/kg - i.m., SID], furosemide [1 mg/kg - i.v., SID for 3 days] and sulfadoxine/trimethoprim [30 mg/kg - i.m., SID for 10 days]. After the initial treatment, the patient showed mild clinical improvement; however, the amaurosis was still present. Magnetic resonance imaging of the brain was performed on the 2nd day of hospitalization, showing a symmetrical hypersignal in the parietal and occipital cortices, in the axial and sagittal sequences weighted in T2 and FLAIR. Discussion: This study aimed to describe the clinical signs and MRI findings in a sheep with PEM. In this case, the sudden change to the feed composition probably led to ruminal dysbiosis, inhibition of thiamine-producing microorganisms and proliferation of bacteria that synthesize thiaminase. Thiamine therapy proved to be effective and capable of reverting the clinical signs. The decrease in the level of consciousness, cortical blindness, and opisthotonus are due to alterations in the parietal cortex, in the occipital cortex, and in the cerebellum, respectively, which were demonstrated by hypersignal areas in the MRI. Therefore, the neurolocalization of the lesion based on neurologic examination and the MRI findings were related. The physicochemical and cytological evaluations of the cerebrospinal fluid, and dosage of thiamine and the concentration of hydrogen sulphide in the rumen were not performed. However, the response to thiamine treatment associated with the neurologic examination and MRI findings helped in determining the diagnosis. Additionally, MRI can be used as a useful tool for the ante mortem diagnosis of PEM.

Chemodectoma in a bitch

Background: Chemodectomas, better known as tumors of the base of the heart, arise from aortic bodies, respiratory chemoreceptors located near or inside the aortic arch or originate from receptors located in the carotid arteries. Relatively rare, they affect dogs and, to a lesser extent, cats. They gain great importance when they influence the function of the cardiovascular system, with animals showing clinical signs related to congestive heart failure. Clinical diagnosis is based on symptomatology and complementary tests such as radiography, electrocardiography and echocardiography, while the definitive diagnosis is obtained by cytological and histopathological exams. This study aims to reports a case of malignant chemodectoma in a bitch, whose main symptomatology was neurological and not cardiovascular. Case: A 1-year-old Rottweiler bitch was attended with neurological alterations compatible with vestibular syndrome, hyporexia, dysphagia, apathy, melena, emesis, and purulent nasal discharge on the right nostril. On physical examination, the animal showed depressed level of consciousness, poor body condition, bilateral quemosis, paralysis of the right eye, inspiratory dyspnea and muffling of cardiac auscultation, besides a subcutaneous nodule between the scapulae. On neurological evaluation, horizontal nystagmus, head tilt to the right side, ventromedial strabismus and facial nerve paralysis on the right side were observed so that the localization of the lesion was set in peripheral vestibular system. During anesthesia for esophageal tube placement, a mass from the hard palate to the oropharynx was noted, making endotracheal intubation impossible to perform. Biopsy of this nodule was performed, and tracheostomy was indicated, but the owner opted for euthanasia before the procedure. Necropsy revealed white soft masses in the bilateral retromandibular region, on the subcutaneous tissue near the scapulae, in the right ear and since nasopharynx to the soft palate, in addition to sparse white nodules in the heart, lung, carotid artery, kidneys, right ovary, mesentery near to the spleen, and axillary lymph node. Histologically, the nodules were characterized by neoplastic cells population organized in short bundles or cords, arranged around small blood vessels surrounded by delicate connective tissue. Neoplastic cells infiltrated muscles and blood and lymphatic vessels were filled by multiple neoplastic emboli. The histological pattern of the cells allowed the diagnosis of chemodectoma. Discussion: The bitch from this case had 1-year-old when diagnosed with chemodectoma, differently from most cases from literature, that are between 7 to 15 years old. Furthermore, primarily cardiac tumors are considered rare, being chemodectoma the most common, often reported in Boxer and Boston Terrier dogs, but unusual in Rottweilers. Despites some articles mentioning seizure and Horner's Syndrome secondary to a carotid body chemodectoma, neurological signs are not commonly observed in these cases. The presence of the tumor in the middle ear region of the right side supports the occurrence of peripheral vestibular syndrome and facial nerve paralysis on the same side. Because it is a neoplasm that is usually detected late during the course of the disorder, most patients either cannot obtain diagnosis in vivo, as in this reported animal, which was in such a critical condition that underwent euthanasia, or there are no more possible therapeutic choices. In the patient described, there were numerous metastatic masses and nodules spread throughout the body. Although the typical clinical signs in animals with chemodectomas are often related to heart disease, neurological signs may also be present. This report emphasizes the importance of chemodectoma being included as a differential diagnosis in young dogs and even in breeds such as Rottweiler.

Canine hypothyroidism with neurological disorders

Background: Hypothyroidism is characterized by hypofunction of the thyroid gland. It results in deficient production of thyroid hormones. Neurological disorders resulting from hypothyroidism are rare, which highlights the importance of this study. This study reports a case of hypothyroidism in a dog with neurological clinical signs, that was treated at the Universidade Estadual de Santa Cruz's Veterinary Hospital (HV-UESC). Case: A 4-year-old male intact Dogo Argentino breed dog, weighing 64 kg, presenting obesity, anorexia, prostration, walking in circles, and chronic dermatopathy was presented at HV-UESC. Upon physical examination, the animal presented a deficit of proprioception in the 4 limbs, with preserved superficial and deep pain. No alteration was observed in the ears, that could explained the clinical signs. In terms of dermatopathy, the animal presented symmetrical alopecia in the lateral region of the thighs and tail. Blood samples were collected for a complete blood count and biochemical tests of urea, creatinine, ALT, AST and cholesterol. Imaging radiography and ultrasonography were performed, which ruled out thoracic and abdominal changes that could be related to the case. Prior to receiving the blood test results, idiopathic encephalitis was suspected and enrofloxacin and prednisone were prescribed for 7 days. During the medication period, previous exams were provided, which indicated only increased cholesterol (500 mg/dL). The animal showed no improvement with the prescribed medication. In view of the clinical signs presented by the patient and the results of the additional tests, hormonal disease was suspected, compatible with hypothyroidism. Thus, hormonal tests of total T4, free T4, and TSH were requested, leading to verification of reduced total T4 (0.3 ng/dL) and free T4 (0.15 ng/dL) levels, and confirming the dysfunction of the thyroid gland. The previous treatment was suspended and thyroid hormone replacement was initiated. After 3 days of treatment, the neurological signs regressed and the animal became more active; after 30 days, the areas of alopecia decreased. Although the patient did not receive the recommended clinical follow-up for such cases, it was possible to establish the ideal levothyroxine dosage for the dog after appropriate adjustments, which permitted thyroid hormone levels to return to normal. Discussion: This report refers to a case of hypothyroidism in a giant dog breed. The dog in the report showed clinical signs of a dermatological, metabolic, and neurological nature, which is consistent with a lack of thyroid hormone. The main signs presented by the animal were neurological, such as walking in circles and a deficit of proprioception in the four limbs. These clinical signs are rarely mentioned in the literature associated with hypothyroidism. Laboratory abnormalities are correlated with the severity and chronicity of the disease. The animal showed a decrease in total T4 and free T4, which is to be expected in a hypothyroid animal. As a result, levothyroxine replacement treatment was initiated. The dose used for the dog, which is the recommended dose in the literature, greatly increased its total T4 levels. As a result, the dose was readjusted after a new clinical evaluation. The rate of metabolism and absorption of levothyroxine varies widely and is independent of weight. The patient showed quickly improvement in neurological signs, activity level, and serum cholesterol rate. Regarding dermatological signs and body condition, there was a more gradual improvement. This corroborates what is mentioned in the literature, which indicates that improvements can take many months

Síndrome da asfixia perinatal em potros / Perinatal asphyxia syndrome in foals

A neonatologia equina é um ramo crescente nos mercados veterinário brasileiro e mundial. Dentre as afecções que acometem o potro neonato, destaca-se a síndrome da asfixia perinatal, a qual é caracterizada por alterações neurológicas e comportamentais. Essa síndrome acomete o neonato desde o terço final da gestação até os 30 primeiros dias de vida. Apesar de ser descrita há décadas na literatura, esta síndrome ainda se caracteriza como um problema atual com relevante prevalência de óbitos. Tal ocorrência é, muitas vezes, devido à demora do diagnóstico e a falta de conhecimento agregado acerca de novos tratamentos mais efetivos, assim como tratamentos tradicionais de suporte. Assim, este trabalho teve como objetivo entender como ocorre à síndrome da asfixia perinatal em potros, identificar os sinais clínicos característicos, abordar tratamentos e divulgar informações que auxiliem na redução das taxas de óbito e de eutanásia dos potros acometidos. Para tal, o trabalho foi desenvolvido com base na revisão bibliográfica integrativa de literatura. O levantamento bibliográfico foi realizado por meio de consulta em base de dados, como Scielo, Google Acadêmico, Portal de Periódicos CAPES e PUBVET, tomando como referência, principalmente, a consulta à Biblioteca Virtual em Medicina Veterinária e Zootecnia (BVS Vet). O trabalho ainda focou na importância de agregar os tratamentos convencionais de suporte ao método alternativo de compressão, na intenção de elevar os índices de sucesso clínico dos potros neonatos acometidos e diminuir as ocorrências de eutanásias, comumente associadas ao alto custo médico aplicado ao animal acometido pela síndrome da asfixia perinatal.

Equine neonatology is an increasing segment in the Brazilian and global veterinary market. Among the disorders that affect the newborn foal, the perinatal asphyxia syndrome, which is characterized by neurological and behavioral changes, stands out. This syndrome affects the newborn from the last third of pregnancy until the first 30 days of life. Despite being described in the literature for decades, the syndrome is still characterized as a current problem with a relevant prevalence of deaths. This occurrence is, often, due to diagnostic delay and lack of aggregated knowledge about new and more effective treatments, as well as traditional supportive treatments. Thus, this study aimed to understand how perinatal asphyxia syndrome occurs in foals, identify the characteristical clinical signs, discuss treatments, and disseminate information that helps reduce the death and euthanasia rates of affected foals. For this purpose, this study was developed based on an integrative literature review. The bibliographic survey was carried out by consulting a database such as Scielo, Google Academic, Periodical's portal CAPES, and PUBVET, referring mainly to the consultation of the Virtual Library in Veterinary Medicine and Animal Science (BVS Vet). The work also focused on the importance of adding the supporting conventional treatments to the alternative squeeze method, intending to increase the clinical success rates of affected newborn foals and reduce the occurrence of euthanasia, commonly associated with the high medical care cost applied to the animal affected by perinatal asphyxia syndrome.

Neuroactive venom compounds obtained from Phlogiellus bundokalbo as potential leads for neurodegenerative diseases: insights on their acetylcholinesterase and beta-secretase inhibitory activities in vitro

Spider venom is a rich cocktail of neuroactive compounds designed to prey capture and defense against predators that act on neuronal membrane proteins, in particular, acetylcholinesterases (AChE) that regulate synaptic transmission through acetylcholine (ACh) hydrolysis - an excitatory neurotransmitter - and beta-secretases (BACE) that primarily cleave amyloid precursor proteins (APP), which are, in turn, relevant in the structural integrity of neurons. The present study provides preliminary evidence on the therapeutic potential of Phlogiellus bundokalbo venom against neurodegenerative diseases. Methods Spider venom was extracted by electrostimulation and fractionated by reverse-phase high-performance liquid chromatography (RP-HPLC) and characterized by matrix-assisted laser desorption ionization-time flight mass spectrometry (MALDI-TOF-MS). Neuroactivity of the whole venom was observed by a neurobehavioral response from Terebrio molitor larvae in vivo and fractions were screened for their inhibitory activities against AChE and BACE in vitro. Results The whole venom from P. bundokalbo demonstrated neuroactivity by inducing excitatory movements from T. molitor for 15 min. Sixteen fractions collected produced diverse mass fragments from MALDI-TOF-MS ranging from 900-4500 Da. Eleven of sixteen fractions demonstrated AChE inhibitory activities with 14.34% (± 2.60e-4) to 62.05% (± 6.40e-5) compared with donepezil which has 86.34% (± 3.90e-5) inhibition (p > 0.05), while none of the fractions were observed to exhibit BACE inhibition. Furthermore, three potent fractions against AChE, F1, F3, and F16 displayed competitive and uncompetitive inhibitions compared to donepezil as the positive control. Conclusion The venom of P. bundokalbo contains compounds that demonstrate neuroactivity and anti-AChE activities in vitro, which could comprise possible therapeutic leads for the development of cholinergic compounds against neurological diseases.(AU)

Neuroactive venom compounds obtained from Phlogiellus bundokalbo as potential leads for neurodegenerative diseases: insights on their acetylcholinesterase and beta-secretase inhibitory activities in vitro

Spider venom is a rich cocktail of neuroactive compounds designed to prey capture and defense against predators that act on neuronal membrane proteins, in particular, acetylcholinesterases (AChE) that regulate synaptic transmission through acetylcholine (ACh) hydrolysis - an excitatory neurotransmitter - and beta-secretases (BACE) that primarily cleave amyloid precursor proteins (APP), which are, in turn, relevant in the structural integrity of neurons. The present study provides preliminary evidence on the therapeutic potential of Phlogiellus bundokalbo venom against neurodegenerative diseases. Methods Spider venom was extracted by electrostimulation and fractionated by reverse-phase high-performance liquid chromatography (RP-HPLC) and characterized by matrix-assisted laser desorption ionization-time flight mass spectrometry (MALDI-TOF-MS). Neuroactivity of the whole venom was observed by a neurobehavioral response from Terebrio molitor larvae in vivo and fractions were screened for their inhibitory activities against AChE and BACE in vitro. Results The whole venom from P. bundokalbo demonstrated neuroactivity by inducing excitatory movements from T. molitor for 15 min. Sixteen fractions collected produced diverse mass fragments from MALDI-TOF-MS ranging from 900-4500 Da. Eleven of sixteen fractions demonstrated AChE inhibitory activities with 14.34% (± 2.60e-4) to 62.05% (± 6.40e-5) compared with donepezil which has 86.34% (± 3.90e-5) inhibition (p > 0.05), while none of the fractions were observed to exhibit BACE inhibition. Furthermore, three potent fractions against AChE, F1, F3, and F16 displayed competitive and uncompetitive inhibitions compared to donepezil as the positive control. Conclusion The venom of P. bundokalbo contains compounds that demonstrate neuroactivity and anti-AChE activities in vitro, which could comprise possible therapeutic leads for the development of cholinergic compounds against neurological diseases.(AU)

Efetividade do cloridrato de ziprasidona sobre distúrbios psicogênicos em cão / Effectiveness of ziprasidone hydrochloride on psychogenic disorders in dog - Case report

O relato discorre sobre a efetividade do antipsicótico cloridrato de ziprasidona como terapia farmacológica para desordens comportamentais em uma cadela apresentando sinais de transtornos neurológicos e episódios de crises convulsivas. Sabendo que há relatos onde a utilização de antipsicóticos em cães foi capaz de amenizar tais sinais, o intuito deste trabalho foi o de avaliar a eficiência da ziprasidona na melhora desta condição, visto que ainda não há registros da aplicabilidade da droga na espécie. No tratamento deste relato de caso foi administrada a dose de 20 mg de ziprasidona a cada 12 horas, com alimento, por um período de três meses. Resultados benéficos foram observados a partir do terceiro dia da administração, quando os sinais foram amenizados e o animal apresentou-se mais equilibrado. Concluiu-se que o fármaco foi capaz de suprimir os sinais indesejados sem causar sedação significativa, e sugere a diminuição na frequência de episódios convulsivos.

The report discusses the effectiveness of the antipsychotic ziprasidone hydrochloride as a pharmacological therapy for behavioral disorders in a dog showing signs of neurological disorders and episodes of seizures. Knowing that there are reports where the use of antipsychotics in dogs was able to mitigate such signs, the aim of this work was to evaluate the efficiency of ziprasidone in improving this condition, since there are still no records of the drug’s applicability in the species. In the treatment of this case report, a dose of 20 mg of ziprasidone was administered every 12 hours, with food, for a period of three months. Beneficial results were observed from the third day of administration, when the signs were reduced and the animal was more balanced. It was concluded that the drug was able to suppress the unwanted signals without causing significant sedation, and suggests a decrease in the frequency of seizure episodes.

Efetividade do cloridrato de ziprasidona sobre distúrbios psicogênicos em cão / Effectiveness of ziprasidone hydrochloride on psychogenic disorders in dog - Case report

O relato discorre sobre a efetividade do antipsicótico cloridrato de ziprasidona como terapia farmacológica para desordens comportamentais em uma cadela apresentando sinais de transtornos neurológicos e episódios de crises convulsivas. Sabendo que há relatos onde a utilização de antipsicóticos em cães foi capaz de amenizar tais sinais, o intuito deste trabalho foi o de avaliar a eficiência da ziprasidona na melhora desta condição, visto que ainda não há registros da aplicabilidade da droga na espécie. No tratamento deste relato de caso foi administrada a dose de 20 mg de ziprasidona a cada 12 horas, com alimento, por um período de três meses. Resultados benéficos foram observados a partir do terceiro dia da administração, quando os sinais foram amenizados e o animal apresentou-se mais equilibrado. Concluiu-se que o fármaco foi capaz de suprimir os sinais indesejados sem causar sedação significativa, e sugere a diminuição na frequência de episódios convulsivos.(AU)

The report discusses the effectiveness of the antipsychotic ziprasidone hydrochloride as a pharmacological therapy for behavioral disorders in a dog showing signs of neurological disorders and episodes of seizures. Knowing that there are reports where the use of antipsychotics in dogs was able to mitigate such signs, the aim of this work was to evaluate the efficiency of ziprasidone in improving this condition, since there are still no records of the drugs applicability in the species. In the treatment of this case report, a dose of 20 mg of ziprasidone was administered every 12 hours, with food, for a period of three months. Beneficial results were observed from the third day of administration, when the signs were reduced and the animal was more balanced. It was concluded that the drug was able to suppress the unwanted signals without causing significant sedation, and suggests a decrease in the frequency of seizure episodes.(AU)

First occurrence of Arnold Chiari type II malformation and associated abnormalities in a Gir calf produced in vitro from Brazil - case report / [Primeira ocorrência de malformação de Arnold Chiari tipo II e anormalidades associadas em uma bezerra Gir de produção in vitro no Brasil - relato de caso]

This study characterized the clinical, radiological, ultrasound, and necroscopic findings of a case of Arnold-Chiari type II malformation in a Gir breed calf from Brazil. The animal was hospitalized at sixty days of age, in permanent sternal recumbency, cutaneous appendix at the 4th lumbar vertebra and kyphoscoliosis of the caudal and lumbosacral thoracic spine. Radiographic examination of the spine and skull revealed spina bifida and suspected occipital hypoplasia. Upon examination of myelography with an injection of lumbar and atlantooccipital contrast, it was possible to visualize the meningocele at the 4th lumbar vertebra region and findings at the rhombencephalon level of increased regional pressure with failure to fill the contrast in the posterior fossa, in the presence of clear demarcation of the circumvolutions of the cerebral cortex and the subarachnoid space of the cervical spinal cord. Ultrasonographic examination of the cerebellum showed an insinuation of the cerebellar worm through the foramen magnum. The animal did not show changes in complete blood count, biochemical series, and cerebrospinal fluid and was negative for Pestivirus. There was a worsening of the clinical conditions and the animal died. This malformation of unknown etiology must be studied as a differential diagnosis of the nervous system disorders.(AU)

Este estudo caracterizou os achados clínicos, radiológicos, ultrassonográficos e necroscópicos de um caso de malformação de Arnold-Chiari tipo II em uma bezerra Gir no Brasil. O animal foi hospilatizado aos 60 dias de idade, apresentando decúbito esternal permanente, apêndice cutâneo na altura da quarta vértebra lombar e cifoescoliose da coluna vertebral torácica caudal e lombossacra. Ao exame radiográfico da coluna e do crânio, foram observadas espinha bífida e suspeita de hipoplasia occipital. Ao exame de mielografia com injeção de contraste lombar e atlanto-occipital, foi possivel visualizar a meningocele na altura da quarta vértebra lombar e achados em nível rombencefálico de aumento da pressão regional com falha de preenchimento do contraste na fossa posterior, na presença de nítida demarcação das circunvoluções do córtex cerebral e do espaço subaracnoide da medula espinhal cervical. Ao exame ultrassonográfico do cerebelo, foi observada insinuação do verme cerebelar através do forame magno. O animal não apresentou alterações em hemograma completo, série bioquímica e fluido cérebro-espinhal e foi negativo para Pestivirus. Houve uma piora do quadro clínico e o animal morreu. Essa malformação de etiologia desconhecida deve ser estudada como um diagnóstico diferencial.(AU)

Outcome of a ceratohyiodectomy in a criollo mare with temporohyoid osteoarthropathy

Background: Temporohyoid osteoarthropathy (THO) is a progressive disease that causes acute onset of peripheral vestibular signs with or without facial paralysis. Ankylosis of temporhyoid joint occurs which predispose to fractures of theinvolved bones and consequently causes the commonly neurological signs observed. Clinical signs vary depending on thestage of the disease and the nerves affected. Surgical treatment is advised to improve survival rates in which the ceratohyoidectomy is currently known as the most advantageous. The aim of the present study is to report a case and outcome ofa ceratohyoidectomy procedure in a Criollo mare presenting THO of the right temporohyoid joint.Case: A 17-year-old Criollo mare was referred to the Equine Clinical Hospital of the Federal University of Pelotas witha 5-day history of facial paralysis on the right side, head tilt and difficulty to chew and swallow. Auricular, palpebraland labial ptosis along with deviation of the lip and nostril to the left were observed. A corneal ulcer was also identifiedin the right eye. Complementary imaging exams (endoscopy of the guttural pouches and radiography of the head) wereperformed and showed thickening of the right stylohyoid bone confirming a diagnosis of THO. Anti-inflammatory andantibiotic therapy were administered and the corneal ulcer was treated with topical antibiotics and autologous serum. Dueto rapid deterioration of clinical signs, the mare was referred to surgery. A ceratohyoidectomty procedure was performedunder general anesthesia. In this procedure, the ceratohyoid bone was disarticulated from the ceratohyoid-basihyoid jointand removed. During the procedure, a branch of the linguofacial vein was accidentally incised causing hemorrhage, thebranch was identified and successfully ligated. Recovery was uneventful. Supportive treatment with anti-inflammatory andantibiotics was continued after surgery and ...

Outcome of a ceratohyiodectomy in a criollo mare with temporohyoid osteoarthropathy

Background: Temporohyoid osteoarthropathy (THO) is a progressive disease that causes acute onset of peripheral vestibular signs with or without facial paralysis. Ankylosis of temporhyoid joint occurs which predispose to fractures of theinvolved bones and consequently causes the commonly neurological signs observed. Clinical signs vary depending on thestage of the disease and the nerves affected. Surgical treatment is advised to improve survival rates in which the ceratohyoidectomy is currently known as the most advantageous. The aim of the present study is to report a case and outcome ofa ceratohyoidectomy procedure in a Criollo mare presenting THO of the right temporohyoid joint.Case: A 17-year-old Criollo mare was referred to the Equine Clinical Hospital of the Federal University of Pelotas witha 5-day history of facial paralysis on the right side, head tilt and difficulty to chew and swallow. Auricular, palpebraland labial ptosis along with deviation of the lip and nostril to the left were observed. A corneal ulcer was also identifiedin the right eye. Complementary imaging exams (endoscopy of the guttural pouches and radiography of the head) wereperformed and showed thickening of the right stylohyoid bone confirming a diagnosis of THO. Anti-inflammatory andantibiotic therapy were administered and the corneal ulcer was treated with topical antibiotics and autologous serum. Dueto rapid deterioration of clinical signs, the mare was referred to surgery. A ceratohyoidectomty procedure was performedunder general anesthesia. In this procedure, the ceratohyoid bone was disarticulated from the ceratohyoid-basihyoid jointand removed. During the procedure, a branch of the linguofacial vein was accidentally incised causing hemorrhage, thebranch was identified and successfully ligated. Recovery was uneventful. Supportive treatment with anti-inflammatory andantibiotics was continued after surgery and ...(AU)