Helen Silveira Coimbra
Universidade Federal de Pelotas
Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by Helen Silveira Coimbra.
Journal of Veterinary Diagnostic Investigation | 2001
Fernando Dutra; Luiz Filipe Damé Schuch; Eduardo Delucchi; Bruna da Rosa Curcio; Helen Silveira Coimbra; Margarida Buss Raffi; Odir Dellagostin; Franklin Riet-Correa
A disease named locally as churrío or churrido equino (i.e., equine scours) has occurred for at least 100 years in Uruguay and southern Brazil in farms along both shores of the Merín lake. This report describes cases of churrido equino and provides serologic, pathologic, and DNA-based evidence indicating that the disease is in fact equine monocytic ehrlichiosis (Potomac horse fever). Results of an epidemiological investigation conducted on an endemic farm are also presented. Clinical signs in 12 horses were fever, depression, diarrhea, dehydration, and sometimes colic and distal hind limb edema. Postmortem findings of 3 horses were of acute enterocolitis. Inclusion bodies containing ehrlichial organisms were found in the cytoplasm of macrophages of the large colon of 1 horse. Eleven of the 12 horses were serologically positive to Ehrlichia risticii (indirect fluorescent antibody assay) and, of 3 paired samples, 2 showed seroconversion. Ehrlichia risticii DNA was identified by a nested polymerase chain reaction in peripheral blood of an affected horse. A healthy horse inoculated with peripheral blood from an affected horse developed the disease and antibodies to E. risticii. The disease had a peak incidence in March (summer) and was statistically associated with a marshy ecosystem near the Merín lake, where large numbers of Pomacea spp. (Ampullariidae) snails were found. Incidence density was almost 8 times higher in nonnative horses than in native horses. It was concluded that the previous diarrheic disease of horses known in Uruguay and southern Brazil as churrido equino is equine monocytic ehrlichiosis.
Pesquisa Veterinaria Brasileira | 2006
Helen Silveira Coimbra; Cristina Gevehr Fernandes; Mauro Pereira Soares; Mário Carlos Araújo Meireles; Roberto Radamés; Luiz Filipe Damé Schuch
A spontaneous outbreak of equine monocytic Ehrlichiosis (EME) is described. The disease occurred from November 2001 to February 2002 on a farm in the municipality of Arroio Grande, located at the western edge of the Mirim Lake, state of Rio Grande do Sul. Out of 50 horses 13 were affected and 6 died. The morbidity was 26% and the mortality 46.1%. The affected horses were 1-5 years old. The most important clinical sign was a profuse acute diarrhea. At necropsy of a horse that died with clinical signs of the disease, the main alterations were characterized by hemorrhagic areas of the mucosa of the large intestine with liquid contents, and congested and hemorrhagic areas alternating with normal areas as well as nodules with purulent secretion in the mucosa of the small intestine. The histological changes were characterized by moderate mononuclear infiltration of the mucosa, characterizing a lympho-histiocytic enteritis with predominance of macrophages. In the jejunum and ileum, related to the invagination of crypts and villi, a granulomatous enteritis was observed. To confirm the diagnosis of infection by Neorickettsia (Ehrlichia) risticii, blood samples of seven affected horses were taken and a polimerase chain reaction (PCR) was performed. Three tested blood samples were positive (42.8%) with observation of a band of 529pb characteristic of N. risticii.
Arquivos do Instituto Biológico | 2013
Helen Silveira Coimbra; Luiz Filipe Damé Schuch; Gertrud Müller; Carolina Lambrech Gonçalves; Cristina Gomes Zambrano; Marta Elaine Bastos Oyarzabal; Luciana de Souza Prestes; Mário Carlos Araújo Meireles
The equine monocytic ehrlichiosis in the region South of the Rio Grande do Sul has demonstrated to be important in the creations of Crioulo horses. It has been reported as cause of diarrhea in equine not surround and as cause of losses with treatments and death of the animals, being pointed as a limited factor in the range breeding in some regions. The way of transmission for the oral way, intermediated for trematodes in aquatic environments, has been supported. Freshwater snails are involved as intermediate hosts of trematodes and harbor of the Neorickettsia risticii. A total of 16,846 Heleobia snails had been collected in the cities of Arroio Grande, Rio Grande, Palmares do Sul and Santa Vitoria do Palmar, 92.2% of which had been found in the roots of aquatics plants (Eichornea spp.). The frequency of trematodes present in the snails varied of 2.3 to 12.8% in the collected regions. Three types of cercariae were found, morphology type 1, morphology type 2 and morphology type 3, and two morphologic type of metacercariae of the snails. A total of 357 insects of the Odonata order were collected, stages of metacercariae had been found in the tissues of suborder Anisoptera with 5.3% of frequency. More studies are necessary for identification of the joined larval phases, as well as knowing the host definitive and identifying the adult parasite and the relation of its cycle of life with the occcurrence of equine monocytic ehrlichiosis.
Ciência Animal Brasileira | 2008
Luiz Filipe Damé Schuch; Jose Maria Wiest; Helen Silveira Coimbra; Luciana de Souza Prestes; Letícia De Toni; Juliana dos Santos Lemos
Acta Scientiae Veterinariae | 2008
Luiz Filipe Damé Schuch; Jose Maria Wiest; Élen Nunes Garcia; Luciana de Souza Prestes; Renata da Costa Schramm; Helen Silveira Coimbra; Mário Carlos Araújo Meireles
Acta Scientiarum. Biological Sciences | 2010
Patrícia da Silva Nascente; Helen Silveira Coimbra; Ana Raquel Mano Meinerz; Mário Carlos Araújo Meireles; Joao Roberto Braga de Mello; Luiz Filipe Damé Schuch
Archive | 2013
Helen Silveira Coimbra; Luiz Filipe; Damé Schuch; Gertrud Müller; Carolina Lambrech Gonçalves; Cristina Gomes Zambrano; Marta Elaine Bastos Oyarzabal; Luciana de Souza Prestes; Mário Carlos; Araújo Meireles
Revista Cubana de Plantas Medicinales | 2011
Fernanda Voigt Mota; Carolina Lambrecht Gonçalves; Luiz Filipe Damé Schuch; Helen Silveira Coimbra; Carla de Andrade Hartwig
Revista Cubana de Plantas Medicinales | 2011
Fernanda Voigt Mota; Carolina Lambrecht Gonçalves; Luiz Filipe Damé Schuch; Helen Silveira Coimbra; Carla de Andrade Hartwig
Archive | 2008
Luiz Filipe; Damé Schuch; Jose Maria Wiest; Élen Nunes Garcia; Luciana de Souza Prestes; Helen Silveira Coimbra; Mário Carlos Araújo Meireles