Hepatozoon spp. in stray cats from the metropolitan area of Rio de Janeiro, Brazil.

In the last few years, the number of studies on feline hepatozoonosis has increased, but our knowledge on the actual species of Hepatozoon and/or different genotypes affecting felines is still incipient. At least three species, namely Hepatozoon felis, H. canis, and H. silvestris, have been isolated from domestic cats in various countries. Additionally, there are indications that other species and genotypes may affect felines in given geographic areas. This study was carried out to investigate the occurrence of Hepatozoon spp. in cats from Niterói, a municipality within the metropolitan area of Rio de Janeiro, Brazil. Individual blood samples were collected from 28 cats enrolled in a spaying/castration program. DNA was extracted from all samples and subjected to sequencing specific for Hepatozoon spp. DNA of H. felis was found in 21/28 cats (75%), and four genetic polymorphisms never described thus far were detected. This is the first report of H. felis in cats living in the State of Rio de Janeiro, and the present data confirm that H. felis is a species complex encompassing different genotypes circulating within cat populations. Further studies are warranted to investigate whether different genotypes have different biology or pathogenicity for felids.

Title: Hepatozoon spp. chez les chats errants de la zone métropolitaine de Rio de Janeiro, Brésil. Abstract: Au cours des dernières années, le nombre d'études sur l'hépatozoonose féline a augmenté, mais nos connaissances sur les espèces d'Hepatozoon et/ou différents génotypes affectant les félins sont encore naissantes. Au moins trois espèces, à savoir Hepatozoon felis, H. canis et H. silvestris, ont été isolées chez des chats domestiques dans divers pays. De plus, il semble que d'autres espèces et génotypes puissent affecter les félins dans des zones géographiques données. Cette étude a été réalisée pour étudier la présence d'Hepatozoon spp. chez des chats de Niterói, une municipalité de la zone métropolitaine de Rio de Janeiro, au Brésil. Des échantillons de sang ont été prélevés individuellement sur 28 chats d'un programme de castration. L'ADN a été extrait de tous les échantillons et soumis à un séquençage spécifique de Hepatozoon spp. L'ADN de H. felis a été trouvé chez 21 chats sur 28 (75%) et quatre polymorphismes génétiques, jamais décrits jusqu'à présent, ont été détectés. Il s'agit du premier signalement de H. felis chez des chats vivant dans l'État de Rio de Janeiro et les données actuelles confirment que H. felis est un complexe d'espèces englobant différents génotypes circulant au sein des populations de chats. Des études supplémentaires sont nécessaires pour déterminer si les différents génotypes ont une biologie ou une pathogénicité différente pour les félidés.

Hemorrhagic Meningoencephalomyelitis Due to Ectopic Localization of Aelurostrongylus abstrusus in a Cat: First Case Report.

The lungworm Aelurostrongylus abstrusus is one of the main causes of respiratory diseases in cats worldwide. This report describes the unusual case of a kitten infected with A. abstrusus and presented to a veterinary clinic in Brazil with lethargy, dysphagia, non-ambulatory tetraplegia, and pelvic limbs bilateral myoclonus. The clinical picture of the kitten worsened with generalized flaccid tetraplegia and death a few days after hospitalization. At necropsy, hemorrhagic necrosis and subarachnoid hemorrhages were detected in several areas of the central nervous system. Nematode stages were found at post-mortem histological examinations in lungs, cerebellum, subarachnoid space of the brain and spinal cord. Microscopic and molecular (PCRs-coupled-sequencing protocols) examination showed the presence of A. abstrusus in histological samples. This study describes the first neurological aelurostrongylosis due to ectopic localization of adult worms in the central nervous system of a cat, causing acute hemorrhagic multifocal meningoencephalomyelitis. Further studies are necessary to elucidate whether unusual localizations and the migration of A. abstrusus are more frequent than expected.

Habronema muscae (Nematoda: Habronematidae) larvae: developmental stages, migration route and morphological changes in Musca domestica (Diptera: Muscidae).

The present paper describes the morphological modifications occurring during the larval development of Habronema muscae (Nematoda: Habronematidae) in Musca domestica (Diptera: Muscidae), along with the reactions caused by parasitism and the migration route of the nematodes inside the flies. Houseflies were reared on faeces of a H. muscae-infected horse, then dissected and processed by histology. The experimental part of the study was performed in 1996 in the Parasitological Experimental Station W.O. Neitz, Federal Rural University of Rio de Janeiro, Seropédica, Rio de Janeiro State, Brazil. Three different larval stages of H. muscae were recovered, measured and described. The encapsulation of larval nematodes was found in the third larval instar (L3) of M. domestica and cryptocephalic pupa. The mature capsules were observed in dipteran L3, pupae and mainly adults. In 1day-old or more M. domestica adults an active rupturing of capsules by H. muscae L3 and the migration to the head through the circulatory system and insect hemocoel were observed. Infective H. muscae L3s remained exclusively in the head of adult 5days-old or more M. domestica.