RESUMO: Polioencefalomalacia (PEM) é uma doença nervosa complexa que afeta ruminantes, tem distribuição mundial e causa perdas econômicas significativas. A PEM é abundantemente descrita e estudada em bovinos e pequenos ruminantes, porém há poucas informações sobre a doença em bubalinos, especialmente no Brasil. O objetivo deste trabalho é descrever os aspectos clínicos e patológicos de um surto de PEM em búfalos em um confinamento no estado do Pará, Brasil. O surto ocorreu em um lote de 76 búfalos da raça Murrah, com idade média de cinco meses, em um sistema de confinamento. Vinte e oito desses bubalinos adoeceram e treze apresentaram sinais neurológicos e morreram. Dois bubalinos foram submetidos à necropsia. O encéfalo e fragmentos de diversos órgãos da cavidade abdominal e torácica foram fixados em formol a 10% e enviados para exame histopatológico. Nos lobos frontal, parietal e occipital do telencéfalo as circunvoluções estavam achatadas e amareladas e ao corte havia uma clara linha de demarcação entre as camadas superficial e profunda. Na histologia as camadas intermediárias do córtex cerebral apresentavam vacuolização leve a moderada do neurópilo, aumento moderado dos espaços perivascular, perineuronal e periastrocitário, tumefação e edema moderados de astrócitos e grande número de neurônios necróticos. O trabalho demonstra que, apesar de pouco documentada no Brasil, a PEM deve ser considerada no diagnóstico diferencial das síndromes neurológicas em bubalinos. RESUMO (PEM ruminantes significativas Brasil Pará 7 Murrah meses morreram necropsia 10 histopatológico frontal profunda neurópilo perivascular periastrocitário necróticos 1

ABSTRACT: Polioencephalomalacia (PEM) is a nervous disease that affects ruminants, has a worldwide distribution and causes significant economic losses. PEM is abundantly described and studied in cattle and small ruminants, but there is little information about the disease in buffaloes, especially in Brazil. The objective of this work is to describe the clinical and pathological aspects of an outbreak of PEM in buffaloes in a feedlot in the state of Pará, Brazil. The outbreak occurred in a flock of 76 Murrah buffaloes, with an average age of five months, in a feedlot. Twenty-eight of these buffaloes became ill, and thirteen showed neurological signs and died. Two buffaloes underwent necropsy. The brain and fragments of various abdominal and thoracic cavity organs were fixed in 10% formalin and sent for histopathological examination. In the frontal, parietal, and occipital telencephalic lobes, the convolutions were flattened and yellowish, and when cut, there was a clear line of demarcation between the superficial and deep layers. Histologically, the intermediate layers of the cerebral cortex showed mild to moderate vacuolization of the neuropil, moderate enlargement of the perivascular, perineuronal, and periastrocyte spaces, moderate swelling and edema of astrocytes, and a large number of necrotic neurons. The work demonstrates that, despite being poorly documented in Brazil, PEM should be considered in the differential diagnosis of neurological syndromes in buffaloes. ABSTRACT (PEM ruminants losses Brazil Pará 7 months Twentyeight Twenty eight ill died necropsy 10 examination frontal parietal lobes yellowish cut Histologically neuropil perivascular perineuronal spaces astrocytes neurons 1

Resumo O objetivo deste trabalho foi avaliar o desenvolvimento e a sobrevivência de larvas de terceiro estágio (L3) de Haemonchus contortus em forrageiras na Amazônia Oriental. Foram utilizados quatro canteiros compostos por Megathyrsus maximus 'Massai', M. maximus 'Mombaça', Urochloa brizantha 'Marandu' e Urochloa humidicola, os quais foram divididos em 13 parcelas cada um. Fezes de ovinos com cerca de 10.000 ovos de H. contortus foram depositadas em cada parcela. Amostras de capim, fezes e solo foram coletadas no no sétimo, no décimo quinto e no trigésimo dia pós-contaminação (DPC) e, sequencialmente, a cada 30 dias até o trecentésimo trigésimo DPC. Foram determinados os seguintes dados das gramíneas: microclimáticos, como temperatura, umidade relativa do ar, umidade do solo e luminosidade do capim, e macroclimáticos, como pluviosidade, temperatura, umidade relativa do ar e radiação solar. As larvas do terceiro estágio foram recuperadas em todas as amostras de gramíneas e solo, em todas as parcelas, do sétimo ao trecentésimo trigésimo DPC. Os parâmetros microclimáticos mostram correlações entre a recuperação de L3 na grama e no solo, e os parâmetros macroclimáticos, entre a recuperação de L3 nas fezes e na grama. Urochloa humidicola e M. maximus 'Massai' favorecem o desenvolvimento e a sobrevivência de L3 de H. contortus, enquanto U. brizantha 'Marandu' e M. maximus 'Mombaça' apresentam menor biodisponibilidade dessas larvas.

Abstract The objective of this work was to evaluate the survival of third-stage larvae (L3) of Haemonchus contortus in forage species in the Eastern Amazon. Four paddocks composed of Megathyrsus maximus 'Massai', M. maximus 'Mombaça', Urochloa brizantha 'Marandu', and Urochloa humidicola were used and divided into 13 plots each. Sheep feces containing about 10,000 eggs of H. contortus were deposited in each plot. Grass, feces, and soil samples were collected on the seventh, fifteenth, and thirtieth day post-contamination (DPC), and, then, they were sequentially collected every 30 days until the three-hundredth and thirtieth DPC. The following data were determined for the grass species: microclimatic, such as temperature, relative humidity, soil moisture, and grass luminosity, as well as macroclimatic data for rainfall, temperature, relative humidity, and solar radiation. L3 were recovered on all grasses and soil samples, in all plots, from the seventh to the three-hundredth and thirtieth DPC. The microclimatic parameters show correlations between the L3 recovery on grass and in the soil, and the macroclimatic parameters, between the L3 recovery in feces and on grass. Urochloa humidicola and M. maximus 'Massai' favor the development and survival of L3 of H. contortus, while U. brizantha 'Marandu' and M. maximus 'Mombaça' show a lower bioavailability of these larvae.

BACKGROUND Non-human primates contribute to the spread of the yellow fever virus (YFV) and the establishment of transmission cycles in endemic areas. OBJECTIVE To describe the severe histopathological aspects of YFV infection, 10 squirrel monkeys were infected with YFV and blood, brain, liver, kidney, spleen, heart, lung, lymph node and stomach were collected at 1-7, 10, 20 and 30 days post-infection (dpi). METHODS Histopathological analysis and detection of the genome and viral antigens and neutralising antibodies were performed by RT-PCR, immunohistochemistry and neutralisation test, respectively. FINDINGS Only one animal died from the experimental infection. The genome and viral antigens were detected in all investigated organs (1-30 dpi) and the neutralising antibodies from seven to 30 dpi. The brain contained perivascular haemorrhage (6 dpi); in the liver, midzonal haemorrhage and lytic necrosis (6 dpi) were observed. The kidney had bleeding in the Bowman’s capsule and tubular necrosis (6 dpi). Pyknotic lymphocytes were observed in the spleen (1-20 dpi), the lung had haemorrhage (2-6 dpi), in the endocardium it contained nuclear pyknosis and necrosis (2-3 dpi) and the stomach contained blood in the lumen (6 dpi). MAIN FINDINGS Squirrel monkeys reliably reproduced the responses observed in human cases of yellow fever and, therefore, constitute an excellent experimental model for studies on the pathophysiology of the disease.

RESUMO: São relatados dois surtos de tripanossomíase por Trypanosoma evansi , em cavalos no município de Chaves, Ilha do Marajó, Pará, Brasil. O primeiro surto ocorreu em abril de 2011 em uma fazenda com 147 cavalos, em que 47 (31,97%) adoeceram e 40 (27,21%) morreram. O segundo ocorreu em maio de 2012 e envolveu nove propriedades. De um total de 679 cavalos, 209 (30,07%) adoeceram e 183 (26,97%) morreram. Os principais sinais clínicos observados foram perda de peso, edema abdominal, emboletamento dos membros e atrofia da musculatura da região pélvica e membros posteriores. A necropsia foi realizada em dois cavalos, um de cada surto. O equino do primeiro surto não apresentou lesões macroscópicas, enquanto o segundo, do segundo surto, apresentava emagrecimento, palidez e icterícia, aumento do baço com protrusão da polpa branca ao corte. O sistema nervoso central de ambos os animais revelou uma leve à severa encefalite linfoplasmocitária, difusa, com presença de células de Mott. A imunohistoquímica para T. evansi revelou estruturas similares a formas tripomastigotas nas lesões. Entre novembro e dezembro de 2013, um levantamento epidemiológico foi realizado nos municípios de Cachoeira do Arari, Santa Cruz do Arari, Salvaterra, Soure e Chaves. Somente Santa Cruz do Arari e Chaves relataram casos da doença. Foram coletadas amostras de sangue de 243 equinos e realizada a reação em cadeia de polimerase (PCR) para a detecção do DNA de T. evansi das quais 20 foram positivas.

ABSTRACT: Two outbreaks of trypanosomiasis by Trypanosoma evansi in horses in the municipality of Chaves, Marajó Island, Pará State, Brazil are reported. The first outbreak occurred in April 2011 in a farm with 147 horses; of these, 47 (31.97%) got sick, and 40 (27.21%) died. The second outbreak occurred in May 2012 and involved nine properties. Of a total of 679 horses, 209 (30.07%) got sick, and 183 (26.97%) died. The main clinical signs observed in these horses were weight loss, abdominal edema, toe dragging, and pelvic muscle atrophy. Necropsy was performed in two horses, one from each outbreak. Macroscopic alterations were not seen in the horse from the first outbreak; however, the horse from the second outbreak exhibited emaciation, pallor and icterus, as well as enlarged spleen with prominent white pulp at cut surface. Histopathology of the central nervous system of both animals revealed mild to severe, diffuse lymphoplasmacytic encephalitis, with presence of Mott cells. Immunohistochemistry for T. evansi revealed structures similar to intralesional trypomastigote forms. Between November and December of 2013, an epidemiological survey was carried out in the municipalities of Cachoeira do Arari, Santa Cruz do Arari, Salvaterra, Soure, and Chaves. Only Santa Cruz do Arari and Chaves had reported cases of the disease. Blood samples were collected from 243 horses for detection of T. evansi DNA by polymerase chain reaction (PCR) and 20 were positive.