Diseases of the central nervous system in swine in Southern Brazil / Doenças do sistema nervoso central de suínos no Sul do Brasil

Brazil is the fourth largest exporter of pork worldwide, with its production concentrated in the Southern region of the country. To reduce the economic impacts and increase herd health, an efficient diagnosis of diseases is necessary. The frequency, seasonal, and annual distribution of diseases that affecting the swine nervous system in Southern Brazil were determined through a retrospective study conducted from 2008 to 2018. A total of 231 pigs were evaluated, and distributed in the following phases: suckling piglets, nursery, growing, finishing, and adults. Piglets in the nursery phase were the most affected with 58.01%. Infectious diseases accounted for 87.01% (201/231) of lesions in the nervous system. Bacterial meningitis was observed in 58.87% of cases, presenting an endemic distribution, and a propensity to occur in the months of autumn/winter. The highest number of cases of porcine circovirus-2 were observed in 2008 and 2009, with a subsequent decline. Porcine circovirus, salt poisoning, and brain abscesses exhibited no association between the seasonal occurrence and annual distribution. Salt poisoning was observed more frequently in the last years of this study. Both, non-suppurative encephalomyelitis and selenium toxicosis exhibited an association between their occurrence and seasonal distribution in, the months of winter, and summer, respectively.(AU)

Brasil é o quarto maior exportador de carne suína do mundo, com sua produção concentrada na região Sul do país. Para reduzir os impactos econômicos e aumentar a saúde do rebanho, é necessário o diagnóstico eficiente das doenças. A frequência, distribuição sazonal e anual das doenças que afetam o sistema nervoso de suínos no Sul do Brasil foram determinadas através de um estudo retrospectivo no período de 2008 a 2018. Foram avaliados 231 suínos, distribuídos nas seguintes fases: maternidade, creche, crescimento, terminação e adultos. Leitões da fase de creche foram os mais afetados com 58,01%. As doenças de origem infecciosa foram responsáveis por 87,01% (201/231) das causas de lesões no sistema nervoso. Meningite bacteriana foi observada em 58,87% dos casos, apresentando distribuição endêmica, e uma tendência a ocorrer nos meses de outono/inverno. O maior número de casos de circovírus suíno foram observados em 2008 e 2009, com declínio posterior. Circovírus suíno, intoxicação por sal e os abscessos encefálicos não apresentaram associação entre a ocorrência sazonal e distribuição anual. A intoxicação por sal foi observada com maior frequência nos últimos anos deste estudo. A encefalomielite não supurativa e a intoxicação por selênio exibiram associação entre a sua ocorrência e distribuição sazonal, nos meses de inverno e verão, respectivamente.(AU)

Primary skin diseases and cutaneous manifestations of systemic diseases in swine / Doenças primárias da pele e manifestações cutâneas de doenças sistêmicas em suínos

Skin diseases in pigs can negatively impact the production. They cause losses related to the death of the affected pigs, to the cost with the treatment, growth retardation and condemnations in the slaughterhouses. This study was developed to determine the frequency and describe the histopathological findings of skin diseases in pigs in different age groups through a retrospective study from 2006 to 2018. A total of 154 conclusive cases were analyzed, including skin restricted diseases (allergic dermatitis, exudative epidermitis, vesicular dermatitis, pityriasis rosea, swinepox, follicular cyst, papilloma and scrotal hemangioma) or skin lesions secondary to systemic diseases (erysipelas, porcine dermatitis and nephropathy syndrome (PDNS), bacterial septicemia and multiple hemorrhages without definite cause). The skin lesions were classified as bacterial (46.1%), viral (26.6%), allergic (12.3%), neoplastic (1.3%) and others (13.6%). Swine erysipelas was the most frequent diagnosis (47/154), followed by PDNS (23/154), allergic dermatitis (19/154) and exudative epidermitis (15/154). Vesicular dermatitis (9/154), pityriasis rosea (9/154), septicemia with cutaneous manifestations (9/154), swinepox (9/154) and multiple hemorrhages without definite cause (7/154) were also observed. Follicular cyst (3/154), hyperkeratosis without definite cause (2/154), papilloma (1/154), and scrotal hemangioma (1/154) were less frequently described. Of the conclusive diagnosis, age was reported in 138 cases, with the highest frequency of skin lesions observed at the inspection process during slaughter (56/138).(AU)

As doenças de pele em suínos podem impactar negativamente a produção. Estas causam perdas relacionadas à morte dos acometidos, a custo com tratamentos, atraso no crescimento e condenações nos frigoríficos. Este trabalho foi desenvolvido para determinar a frequência e descrever os achados histopatológicos das doenças de pele em suínos nas diferentes faixas etárias, através de um estudo retrospectivo no período de 2006 a 2018. Foram analisados 154 casos conclusivos incluindo as doenças restritas a pele (dermatites alérgicas, epidermite exsudativa, dermatite vesicular, pitiríase rósea, varíola suína, cisto folicular, papiloma e hemangioma escrotal) e as secundárias a doenças sistêmicas (erisipela, síndrome dermatite nefropatia suína (SDNS), septicemia bacteriana e hemorragias múltiplas de causa não determinada). Estas foram classificadas em bacterianas (46,1%), virais (26,6%), alérgicas (12,3%), neoplásicas (1,3%) e outras (13,6%). A erisipela suína foi a enfermidade mais diagnosticada (47/154), seguida por SDNS (23/154), dermatite alérgica (19/154) e epidermite exsudativa (15/154). Observamos ainda dermatite vesicular (9/154), pitiríase rósea (9/154), septicemia bacteriana com manifestações cutâneas (9/154), varíola suína (9/154) e hemorragias múltiplas de causa não determinada (7/154). Em menor número, cisto folicular (3/154), hiperqueratose sem causa definida (2/154), papiloma (1/154) e hemangioma escrotal (1/154). Dos casos conclusivos, a idade foi informada em 138 casos, sendo a maior frequência das lesões de pele observadas na linha de inspeção, durante o abate (56/138).(AU)

GASTRIC PYTHIOSIS IN A BACTRIAN CAMEL ( BACTRIANUS CAMELUS).

Pythium insidiosum, an aquatic oomycete, causes chronic lesions in the skin and digestive tract of multiple species. A captive-bred Bactrian camel ( Camelus bactrianus) showed clinical signs of lethargy and weight loss in a clinical course of 30 days, with no response to treatment. At necropsy, the abdominal cavity had approximately 32 L of a yellow, turbid fluid with fibrin. The third compartment of the stomach (C-3) showed a focal area of rupture covered with fibrin. Close to this area, the C-3 wall was thickened and firm, demonstrating irregular, yellow, and friable areas on cut surface (kunkers). Microscopically, these corresponded to necrosis, characterized by a central amorphous eosinophilic material, surrounded by a pyogranulomatous inflammatory infiltrate and fibrosis. Negatively stained hyphae were observed at the periphery of the necrotic areas, which showed marked immunostaining for P. insidiosum. Pythiosis in camelids may involve the stomach, resulting in peritonitis and death.

Infecção pelo vírus influenza A em suínos no sul de Moçambique / Influenza A virus infection in pigs in southern Mozambique

A influenza suína (IS) é uma doença aguda e altamente contagiosa do trato respiratório de suínos, causada pelo vírus influenza A (VIA). A doença provoca perdas econômicas na suinocultura e também, tem importância na saúde pública devido ao seu potencial zoonótico. O objetivo deste trabalho foi relatar a infecção pelo VIA em suínos de Moçambique e realizar a caracterização anatomopatológica e imuno-histoquímica (IHQ) das lesões pulmonares associadas. Pulmões de 457 suínos abatidos foram avaliados e coletados 38 (8,3%) pulmões de suínos com áreas de consolidação pulmonar em um abatedouro na cidade da Matola, no Sul de Moçambique. As áreas de consolidação em cada lobo pulmonar foram classificadas em 4 graus de acordo com a extensão da lesão. Amostras de pulmões com consolidação foram submetidas ao exame histopatológico e IHQ para a detecção de antígenos do VIA, Circovírus suíno tipo 2 (PCV2) e Mycoplasma hyopneumoniae. Os pulmões coletados apresentaram áreas multifocais ou coalescentes de consolidação pulmonar, frequentemente, observadas nos lobos craniais, mediais e acessório. Estas lesões acometiam principalmente um ou três lobos pulmonares e as lesões de grau 1 e 2 foram as mais frequentes. As principais lesões histopatológicas observadas foram bronquiolite necrotizante (23/38), infiltrado de neutrófilos nos alvéolos (24/38), hiperplasia de pneumócitos tipo II (26/38), hiperplasia de tecido linfoide peribronquiolar (28/38), e pneumonia intersticial mononuclear (29/38). No exame de IHQ, antígenos do VIA foram detectados em 84.3% (32/38) dos pulmões com pneumonia, e a nucleoproteína do vírus foi visualizada, no núcleo de células epiteliais de brônquios e bronquíolos e em macrófagos alveolares. Suínos positivos para o VIA na IHQ eram provenientes do distrito de Matutuine (5/32), distrito da Moamba (2/32), distrito de Namaacha (21/32), distrito de Boane (3/32) e Cidade da Matola (1/32). Todas as amostras foram negativas para PCV2 e Mycoplasma hyopneumoniae pelo exame de IHQ. Os resultados demonstram que o VIA está presente e é causa de pneumonia em suínos em Moçambique.(AU)

Swine influenza (SI) is an acute and highly contagious disease of the respiratory tract of pigs caused by influenza A virus (IAV). The disease causes economic losses in swine production and is of great public importance for its zoonotic potential. The aim of the present study was to report IAV infection in pigs from Mozambique and characterize the anatomopathological and immunohistochemical features of associated lung lesions. Lungs from 457 slaughtered pigs were subjected to gross evaluation and 38 (8.3%) lungs with cranioventral consolidation were collected from a slaughterhouse in Matola City, southern Mozambique. Areas of consolidation in each lung lobe were classified in 4 grades according to the lesion extension. Samples with consolidated lung tissue were examined for histopathology and immunohistochemistry (IHC) for the presence of IAV, Porcine circovirus type 2 (PCV2) and Mycoplasma hyopneumoniae antigens. The lungs had multifocal to coalescing areas of consolidation observed most frequently in the cranial, middle, and accessory lobes. The lesions involved mainly one or three pulmonary lobes and grade 1 and 2 lesions were the most frequent. The main histopathological findings were necrotizing bronchiolitis (23/38), alveolar neutrophil infiltration (24/38), type II pneumocytes hyperplasia (26/38), peribronchiolar lymphoid tissue hyperplasia (28/38) and interstitial mononuclear cells infiltrate (29/38). Immunohistochemistry revealed positive staining in 84.3% (32/38) of the samples and IAV nucleoprotein was present in the nucleus of bronchial and bronchiolar epithelial cells and alveolar macrophages. Positive IHC pigs were from Matutuine district (5/32), Moamba district (2/32), Namaacha district (21/32), Boane district (3/32) and Matola city (1/32). All lung samples were immunohistochemically negative for PCV2 and Mycoplasma hyopneumoniae. These results demonstrate that IAV is a cause of pneumonia in pigs in Mozambique.(AU)

Achados patológicos e imuno-histoquímicos de neoplasmas pulmonares primários em caninos na região metropolitana de Porto Alegre, Rio Grande do Sul / Pathological and immunohistochemical findings of primary pulmonary neoplams in dogs in the metropolitan region of Porto Alegre, Rio Grande do Sul

Neoplasmas pulmonares primários são pouco frequentes na medicina veterinária, mas a principal espécie afetada é a canina. Acredita-se que o número de neoplasmas pulmonares primários vem aumentando em animais de companhia, em decorrência do aumento da expectativa de vida, da melhora nas técnicas de diagnóstico e pelo maior contato com poluentes atmosféricos. Este estudo foi realizado para identificar, analisar a frequência, e caracterizar achados patológicos e imuno-histoquímicos dos neoplasmas pulmonares primários em cães na região metropolitana de Porto Alegre, Rio Grande do Sul. No período de janeiro de 2003 a junho de 2016 foram submetidos à necropsia 6.307 caninos. Destes, 36 cães tinham diagnóstico de neoplasma pulmonar primário. O neoplasma mais frequente neste estudo foi o adenocarcinoma papilar (30,5%), seguido do carcinoma lepídico (22,2%). A idade dos cães variou de quatro a 16 anos, com média de 11 anos. Observou-se que a frequência de cães machos (63,9%) prevaleceu sobre as fêmeas (36,1%). Na avaliação imuno-histoquímica, todos os neoplasmas epiteliais foram positivos para pancitoqueratina, 70,6% foram positivos para fator de transcrição de tireoide-1 e 23,5% tiveram coexpressão de pancitoqueratina e vimentina. Dois tumores mesenquimais tiveram imunomarcação para vimentina e S-100, foram negativos para a imuno-histoquímica de actina de músculo liso e melan-A e para a técnica histoquímica de tricrômico de Masson e foram diagnosticados como tumor da bainha de nervo periférico maligno, raramente encontrado como tumor primário de pulmão em animais. Quando é difícil estabelecer um diagnóstico apenas com o exame histológico de rotina, é necessário ressaltar a importância da técnica de imuno-histoquímica para o diagnóstico de neoplasmas pulmonares primários em cães.(AU)

Primary pulmonary neoplasms are uncommon in veterinary medicine; but most frequently affected are dogs. It appears that the number of primary pulmonary neoplasms is increasing in companion animals, due to the increase in life expectancy, improvement of diagnostic techniques and greater contact with air pollutants. This study was realized to identify, analyze the frequency, and to characterize pathological and immunohistochemical findings of primary pulmonary neoplasms in dogs of the metropolitan region of Porto Alegre, Rio Grande do Sul. From January 2003 to June 2016, 6,037 necropsies were performed and in 36 of them primary pulmonary neoplasm was found. The most frequent neoplasm in this study was papillary adenocarcinoma (30.5%) followed by lepidic adenocarcinoma (22.2%). The age of affected dogs ranged from 4 to 16 years, with a mean of 11 years. The frequency of male dogs (63.9%) prevailed over females (36.1%). Through immunohistochemical evaluation all epithelial neoplasms were positive for pancytokeratin, 70.6% were positive for thyroid-1 transcription factor and 23.5% had co-expression of pancytokeratin and vimentin. Two mesenchymal tumors showed immunostaining for vimentin and S-100, were negative for smooth-muscle actin and melan-A immunohistochemistry and Masson's trichrome histochemical technique and were diagnosed as malignant peripheral nerve sheath tumors, rarely found as primary lung tumor in animals. If one has difficulty to establish a diagnosis only through routine histological examination, it is necessary to emphasize the importance of the immunohistochemical technique for the diagnosis of primary pulmonary neoplasms in dogs.(AU)

Lesões intestinais em suínos abatidos no Rio Grande do Sul / Intestinal lesions in pigs slaughtered in Rio Grande do Sul, Brazil

O Rio Grande do Sul se destaca na suinocultura nacional pelos altos índices de produção, baseada em sistema de criação intensivo, fato que propicia a ocorrência de doenças entéricas. Este estudo foi realizado para diagnosticar e determinar a frequência das causas de condenação de intestinos na linha de abate. As amostras de intestino e linfonodos mesentéricos foram colhidas para análise histológica e imuno-histoquímica, de um frigorífico de suínos localizado na Região do Vale do Taquari, no Rio Grande do Sul (RS), que conta com Serviço de Inspeção Federal (SIF). A colheita ocorreu durante 18 dias nos meses de verão (janeiro e fevereiro) e 19 dias nos meses de inverno (junho, julho e agosto) de 2016. Os suínos eram provenientes de 55 municípios diferentes, que fazem parte de sete microrregiões do RS (microrregião de Passo Fundo, Soledade, Guaporé, Santa Cruz do Sul, Lajeado-Estrela, Montenegro e São Jerônimo). Dos 2.523 intestinos condenados no verão e 2.747 no inverno, 216 e 199 foram avaliados, respectivamente. Os três principais diagnósticos foram serosite crônica (43,1%), ascaridiose (21,4%) e enteropatia proliferativa suína (20%), seguidos por casos de tampão caseoso em válvula ileocecal (5,0%), abscesso intestinal (1,0%), pneumatose (1,0%), circovirose (0,7%), esofagostomíase (0,7%), salmonelose (0,7%) e um caso de intussuscepção (0,2%). A serosite crônica foi diagnosticada em 82/216 (38%) no verão e 97/199 (48,7%) no inverno, ascaridiose teve maior ocorrência no verão com 64/216 (29,6%) comparado com o inverno em que observou-se 25/199 (12,6%). A enteropatia proliferativa suína foi diagnosticada em 37/216 (17,1%) casos no verão e 46/199 (23,1%) no inverno.(AU)

Rio Grande do Sul stands out in the national swine industry due to high production rates, based on an intensive breeding system, which leads to the occurrence of enteric diseases. This study was performed to diagnose and determine the frequency of causes of bowel condemnation in the slaughter line. The samples of intestine and mesenteric lymph nodes were collected for histological and immunohistochemical analysis of a pig slaughterhouse located in the Vale do Taquari area, in Rio Grande do Sul (RS), which has Federal Meat Inspection Service (SIF). The collection occurred during 18 days in the summer (January and February) and 19 days during winter (June, July and August) of 2016. The pigs were from 55 different counties from of seven microregions of RS (microregion of Passo Fundo, Soledade, Guaporé, Santa Cruz do Sul, Lajeado-Estrela, Montenegro and São Jerônimo). Out of 2,523 condemned intestines in the summer and 2,747 in the winter, 216 and 199 were evaluated, respectively. The three main diagnoses were chronic serositis (43.1%), ascaridiosis (21.4%), and porcine proliferative enteropathy (20%), followed by cases of plug caseous in ileocecal valve (5.0%), intestinal abscess (1.0%), pneumatosis (1.0%), circovirosis (0.7%), oesophagostomiasis (0.7%), salmonellosis (0.7%) and a case of intussusception (0.2%). Chronic serositis was diagnosed in 82/216 (38%) in summer and 97/199 (48.7%) in winter, ascaridiosis had a higher occurrence in the summer with 64/216 (29.6%) compared to the winter when it was observed 25/199 (12.6%). Porcine proliferative enteropathy was diagnosed in 37/216 (17.1%) in summer and 46/199 (23.1%) in winter.(AU)

Detection and phylogenetic characterization of porcine circovirus 2 from pigs in Mozambique.

Porcine circovirus-associated diseases (PCVADs), caused by porcine circovirus 2 (PCV-2), have a significant economic impact on the swine industry worldwide. In Africa, there is little information, to date, regarding the occurrence of PCV-2, and it has not been reported in Mozambique's swine population. We randomly collected mesenteric lymph nodes ( n = 111) from slaughtered pigs from 9 districts in southern Mozambique. PCV-2 DNA was detected in 54% (62 of 111) of the samples and 78% (23 of 31) of the farms. PCV-2 antigen was detected by immunohistochemistry in lymph nodes (6 of 62; 10%) that were positive for PCV-2 by PCR. Histopathologic changes observed in these lymph nodes were lymphoid depletion, multifocal nodal necrosis, and infiltrates of histiocytes and multinucleate giant cells. One positive sample from each district was selected in order to obtain sequences covering the ORF2 region. Five sequences clustered with PCV-2d, of which 3 sequences from Maputo, Namaacha, and Moamba were grouped with PCV-2d-2; 2 sequences from Manhiça and Matola were grouped as PCV-2d-1; and 4 sequences from Boane, Matutuíne, Chibuto, and Xai-Xai were closely related to PCV-2b-1A/B genotypes. Our study indicates that a diversity of PCV-2 viruses is circulating in the Mozambican swine population.

Aspectos epidemiológicos, clínicos e anatomopatológicos do linfoma em bovinos: 128 casos (1965-2013) / Epidemiological, clinical and pathological aspects of lymphoma in cattle: 128 cases (1965-2013)

Por meio de um estudo retrospectivo, os aspectos epidemiológicos, clínicos e anatomopatológicos de 128 casos de linfoma bovino são descritos. Dos protocolos que informavam o sexo (n=111), 84,7% correspondiam a fêmeas e 15,3% a machos. Dos protocolos em que constava a raça (n=108), a mais prevalente foi a holandesa (63%). Em relação à idade (n=107), houve uma variação entre um e 14 anos. A maioria dos bovinos era adulta (89,7%) e a maior concentração dos casos ocorreu ao redor de 5-8 anos (57,9%). Em relação aos sinais clínicos (n=89), linfadenomegalia foi o achado mais frequentemente observado (74,1%). Outros sinais clínicos, principalmente aqueles relacionados com os sistemas respiratório (dispneia, estertoração pulmonar e taquipneia), cardiovascular (taquicardia, edema subcutâneo e pulso venoso positivo), digestório (atonia ruminal, timpanismo e diarreia) e nervoso (paresia dos membros pélvicos e andar cambaleante), foram pouco prevalentes. Na necropsia (n=125), 71,2% dos bovinos apresentavam aumento de volume dos linfonodos; essa linfadenomegalia foi classificada como localizada em 89,6% dos casos e generalizada em 10,3% dos casos. Dos protocolos que informavam os linfonodos acometidos (n=58), a distribuição foi a seguinte: mesentéricos (51,7%), mediastínicos (37,9%), pré-escapulares (29,3%), ilíacos internos (27,6%), inguinais superficiais (25,8%) e traqueobrônquicos (18,9%). Além dos linfonodos, outros órgãos comumente afetados pelo linfoma neste estudo incluíram: coração (40%), fígado (15,2%), rim (14,4%), abomaso (12,8%), útero (11,2%), intestino (10,4%) e pulmão (7,2%)...

The epidemiological, clinical and pathological aspects of 128 cases of bovine lymphoma are described in this study. Out of the cases were the gender was informed (n=111), 84.7% of affected animals were females and 15.3% were males. Out of the cases were breed was informed (n=108), 63% of affected animals were Holstein cows. The age of affected cows (n=107) varied from 1 to 14 years (57.9%), with most animals being adults (89.7%) with 5 to 8 years of age (57.9%). The most common clinical sign (n=89) was lymphadenomegaly (74.1%). Other clinical signs associated with the respiratory system (dyspnea, pulmonary stridor, and tachypnea), cardiovascular system (tachycardia, subcutaneous edema, and positive venous pulse), digestive system (ruminal atony, bloat, and diarrhea), and nervous system (pelvic limb paresis and staggering pace) were less prevalent. Gross findings (n=125) included enlargement of lymph nodes in 71.2% of the cases; this finding was classified as localized in 89.6% of the cases and generalized in 10.3% of the cases. Out of the cases where the affected lymph nodes were identified (n=58) the distribution of the lymphadenomegaly was the following: mesenteric (51.7%), mediastinal (37.9%), prescapular (29.3%), internal iliac (27.6%), superficial inguinal (25.8%), and tracheobronchial (18.9%). Other commonly affected organs included heart (40%), liver (15.2%), kidney (14.4%), abomasum (12.8%), uterus (11.2%), intestine (10.4%), and lung (7.2%)...

Aspectos epidemiológicos, clínicos e anatomopatológicos da intoxicação por aceturato de diminazeno em cães / Epidemiological, clinical, and pathological aspects of diminazene aceturate toxicosis in dogs

Os aspectos epidemiológicos, clínicos e anatomopatológicos da intoxicação espontânea por aceturato de diminazeno foram estudados em 10 cães. Em todos os casos, os cães afetados demonstraram sinais de síndrome tálamo-cortical, principalmente alteração do nível de consciência, tetraparesia, rigidez extensora e crise convulsiva. Em alguns casos, os cães acometidos apresentaram sinais de síndrome cerebelar, como tremores musculares generalizados de alta frequência e baixa amplitude, e/ou de síndrome vestibular, como ataxia, inclinação de cabeça e quedas. Esses sinais ocorreram entre 24 e 48 horas após o uso do fármaco injetável por via intramuscular e se mantiveram até a morte ou eutanásia dos cães (entre 1 e 7 dias). Tais sinais clínicos refletiam encefalomalacia hemorrágica focal simétrica, que afetava a medula oblonga, a ponte, a medular do cerebelo, o tálamo, o mesencéfalo, os pedúnculos cerebelares e os núcleos da base. Esse artigo: 1) descreve e discute essa forma de intoxicação medicamentosa tão pouco citada na literatura internacional e desconhecida da maior parte dos clínicos e patologistas veterinários brasileiros, 2) estabelece critérios clínicos e anatomopatológicos para o seu diagnóstico e, principalmente, 3) atenta para os riscos da utilização desse princípio ativo na terapêutica canina.

The epidemiological, clinical, and pathological aspects of diminazene aceturate (DA) spontaneous toxicosis were evaluated in 10 dogs. All affected dogs developed signs of thalamic-cortical syndrome, characterized mainly by neurological changes in the conscience levels, tetraparesis, extensor stiffness, and seizures. In some cases there was also evidence of cerebellar syndrome, characterized by generalized muscle tremors (high-frequency and low-amplitude) and/or vestibular syndrome, characterized by or ataxia, head tilt, and falling. These clinical signs occurred between 24 and 48 hours following intramuscular administration of DA and persisted until spontaneous death or euthanasia occurred between 1 and 7 days after the onset of clinical signs. The mentioned clinical signs reflected lesions that consisted of focal symmetrical hemorrhagic encephalomalacia affecting medulla oblongata, pons, cerebellar medulla, thalamus, midbrain, cerebellar peduncles, and basal nuclei. This article (1) describes and discusses DA toxicosis in dogs, a poorly-described clinical entity that is unknown by most clinicians and pathologists in Brazil; (2) establishes the clinical and pathological criteria for the diagnosis of DA toxicosis in dogs; and (3) calls up the attention for the risks of using DA in dogs in clinical settings.

Trypanosoma evansi infection impairs memory, increases anxiety behaviour and alters neurochemical parameters in rats.

The aim of this study was to investigate neurochemical and enzymatic changes in rats infected with Trypanosoma evansi, and their interference in the cognitive parameters. Behavioural assessment (assessment of cognitive performance), evaluation of cerebral L-[3H]glutamate uptake, acetylcholinesterase (AChE) activity and Ca+2 and Na+, K+-ATPase activity were evaluated at 5 and 30 days post infection (dpi). This study demonstrates a cognitive impairment in rats infected with T. evansi. At 5 dpi memory deficit was demonstrated by an inhibitory avoidance test. With the chronicity of the disease (30 dpi) animals showed anxiety symptoms. It is possible the inhibition of cerebral Na+, K+-ATPase activity, AChE and synaptosomal glutamate uptake are involved in cognitive impairment in infected rats by T. evansi. The understanding of cerebral host­parasite relationship may shed some light on the cryptic symptoms of animals and possibly human infection where patients often present with other central nervous system (CNS) disorders.