Toxoplasma gondii in cetaceans of Brazil: a histopathological and immunohistochemical survey.

Toxoplasmosis is a parasitic disease caused by the protozoan Toxoplasma gondii. In cetaceans, T. gondii infection is a significant cause of morbidity and mortality. Despite the worldwide range and broad cetacean host record of T. gondii infection, there is limited information on toxoplasmosis in cetaceans from the Southern hemisphere. We investigated the occurrence of T. gondii by histopathology and immunohistochemistry in tissue samples of 185 animals comprising 20 different cetacean species from Brazil. Three out of 185 (1.6%) animals presented T. gondii-associated lesions: a captive killer whale Orcinus orca, a free-ranging common bottlenose dolphin Tursiops truncatus and a free-ranging Guiana dolphin Sotalia guianensis. The main lesions observed in these animals were necrotizing hepatitis, adrenalitis and lymphadenitis associated with protozoal cysts or extracellular tachyzoites presenting immunolabeling with anti-T. gondii antibodies. This study widens the spectrum of species and the geographic range of this agent in Brazil, and provides the first reports of T. gondii infection in a captive killer whale and in a free-ranging common bottlenose dolphin in South America.

Toxoplasma gondii in cetaceans of Brazil: a histopathological and immunohistochemical survey / Toxoplasma gondii em cetáceos do Brasil: estudo histopatológico e imuno-histoquímico

Abstract Toxoplasmosis is a parasitic disease caused by the protozoan Toxoplasma gondii. In cetaceans, T. gondii infection is a significant cause of morbidity and mortality. Despite the worldwide range and broad cetacean host record of T. gondii infection, there is limited information on toxoplasmosis in cetaceans from the Southern hemisphere. We investigated the occurrence of T. gondii by histopathology and immunohistochemistry in tissue samples of 185 animals comprising 20 different cetacean species from Brazil. Three out of 185 (1.6%) animals presented T. gondii-associated lesions: a captive killer whale Orcinus orca, a free-ranging common bottlenose dolphin Tursiops truncatus and a free-ranging Guiana dolphin Sotalia guianensis. The main lesions observed in these animals were necrotizing hepatitis, adrenalitis and lymphadenitis associated with protozoal cysts or extracellular tachyzoites presenting immunolabeling with anti-T. gondii antibodies. This study widens the spectrum of species and the geographic range of this agent in Brazil, and provides the first reports of T. gondii infection in a captive killer whale and in a free-ranging common bottlenose dolphin in South America.

Resumo Toxoplasmose é uma doença parasitária causada pelo protozoário Toxoplasma gondii. A infecção por T. gondii é uma causa significativa de morbidade e mortalidade, nos cetáceos. Apesar da abrangência mundial e amplo registro de espécies de cetáceos infectadas por T. gondii, informações sobre toxoplasmose em cetáceos do hemisfério sul são limitadas. Neste estudo pesquisou-se por meio de histopatologia e imuno-histoquímica a ocorrência de T. gondii em amostras de tecido de 185 animais, compreendendo 20 diferentes espécies de cetáceos que ocorrem no Brasil. Três dos 185 (1,6%) animais apresentaram lesões associadas a T. gondii: uma orca Orcinus orca mantida em cativeiro, um golfinho-nariz-de-garrafa Tursiops truncatus e um boto-cinza Sotalia guianensis de vida livre. As principais lesões observadas nesses animais foram hepatite, adrenalite e linfadenite necrotizantes associadas a cistos protozoários ou taquizoítos extracelulares, marcados com anticorpos anti-T. gondii. O presente estudo amplia o espectro de espécies susceptíveis a esse agente e o seu alcance geográfico no Brasil, fornecendo o primeiro relato da infecção por T. gondii em uma orca mantida em cativeiro e em um golfinho-nariz-de-garrafa de vida livre na América do Sul.

Ultrastructural Description of Sarcocystis Sp. in Cardiac Muscle of Naturally Infected Alpacas (Vicugna pacos).

BACKGROUND: Recently, it was proposed the name of Sarcocystis masoni n. sp. for the Sarcocystis that causes microcyst in skeletal muscle of South American camelids. However, there are no ultrastructural reports of microcysts of Sarcocystis in cardiac muscle of alpacas. This study reports ultrastructural features of microcysts of Sarcocystis sp. from cardiac muscle of naturally infected alpacas. METHODS: Thirty alpacas (age range: three to five years) from the province of Junin, Peruvian Central Andes, were included in this study in January 2015. Cardiac muscle samples were evaluated by histology and transmission electron microscopy. RESULTS: Bradyzoites in cysts had typical characteristics of Apicomplexa including organelles, a large nucleus, micronemes, dense bodies, and polysaccharide granules. Moreover, cysts had a thin wall with numerous, short, finger-like shapes with rounded tip protrusions (0.51 × 0.17 µm). CONCLUSION: Sarcocystis sp. from the heart and S. masoni n. sp. from the skeletal muscle have similar ultrastructural characteristics.

Toxoplasma gondii in cetaceans of Brazil: a histopathological and immunohistochemical survey / Toxoplasma gondii em cetáceos do Brasil: estudo histopatológico e imuno-histoquímico

Toxoplasmosis is a parasitic disease caused by the protozoan Toxoplasma gondii. In cetaceans, T. gondii infection is a significant cause of morbidity and mortality. Despite the worldwide range and broad cetacean host record of T. gondii infection, there is limited information on toxoplasmosis in cetaceans from the Southern hemisphere. We investigated the occurrence of T. gondii by histopathology and immunohistochemistry in tissue samples of 185 animals comprising 20 different cetacean species from Brazil. Three out of 185 (1.6%) animals presented T. gondii-associated lesions: a captive killer whale Orcinus orca, a free-ranging common bottlenose dolphin Tursiops truncatus and a free-ranging Guiana dolphin Sotalia guianensis. The main lesions observed in these animals were necrotizing hepatitis, adrenalitis and lymphadenitis associated with protozoal cysts or extracellular tachyzoites presenting immunolabeling with anti-T. gondii antibodies. This study widens the spectrum of species and the geographic range of this agent in Brazil, and provides the first reports of T. gondii infection in a captive killer whale and in a free-ranging common bottlenose dolphin in South America.(AU)

Toxoplasmose é uma doença parasitária causada pelo protozoário Toxoplasma gondii. A infecção por T. gondii é uma causa significativa de morbidade e mortalidade, nos cetáceos. Apesar da abrangência mundial e amplo registro de espécies de cetáceos infectadas por T. gondii, informações sobre toxoplasmose em cetáceos do hemisfério sul são limitadas. Neste estudo pesquisou-se por meio de histopatologia e imuno-histoquímica a ocorrência de T. gondii em amostras de tecido de 185 animais, compreendendo 20 diferentes espécies de cetáceos que ocorrem no Brasil. Três dos 185 (1,6%) animais apresentaram lesões associadas a T. gondii: uma orca Orcinus orca mantida em cativeiro, um golfinho-nariz-de-garrafa Tursiops truncatus e um boto-cinza Sotalia guianensis de vida livre. As principais lesões observadas nesses animais foram hepatite, adrenalite e linfadenite necrotizantes associadas a cistos protozoários ou taquizoítos extracelulares, marcados com anticorpos anti-T. gondii. O presente estudo amplia o espectro de espécies susceptíveis a esse agente e o seu alcance geográfico no Brasil, fornecendo o primeiro relato da infecção por T. gondii em uma orca mantida em cativeiro e em um golfinho-nariz-de-garrafa de vida livre na América do Sul.(AU)

Molecular identification and microscopic characterization of poxvirus in a Guiana dolphin and a common bottlenose dolphin, Brazil.

The poxviruses identified in cetaceans are associated with characteristic tattoo or ring skin lesions. However, little is known regarding the prevalence and progression of these lesions and the molecular characterization of cetacean poxviruses in the Southern Hemisphere. This manuscript describes the progression of poxvirus-like skin lesions in 5 free-ranging Guiana dolphins Sotalia guianensis. Additionally, 151 skin samples from 113 free-ranging cetaceans from Brazil, including 4 animals with tattoo skin lesions, were selected for poxvirus testing. Poxviral DNA polymerase gene PCR amplification was used to detect the virus in ß-actin-positive samples (145/151). DNA topoisomerase I gene PCR was then used in Cetaceanpoxvirus (CePV)-positive cases (n = 2), which were further evaluated by histopathology and electron microscopy. Based on photo-identification, adult Guiana dolphins presented regressing or healed poxvirus-like lesions (2/2), while juveniles presented persistent (2/3) or healed and progressive lesions (1/3). CePV DNA was amplified in a common bottlenose dolphin Tursiops truncatus and in a Guiana dolphin. Intracytoplasmic inclusion bodies and viral particles consistent with poxvirus were identified by histology and electron microscopy, respectively. CePV-specific amino acid motifs were identified through phylogenetic analysis. Our findings corroborate previous studies that suggest the placement of poxviruses from cetaceans within the novel CePV genus. This is the first molecular identification of poxvirus in South American odontocetes.

Fatal haemorrhage and neoplastic thrombosis in a captive African lion (Panthera leo) with metastatic testicular sex cord-stromal tumour.

BACKGROUND: The study of neoplasia in wildlife species contributes to the understanding of cancer biology, management practices, and comparative pathology. Higher frequencies of neoplasms among captive non-domestic felids have been reported most commonly in aging individuals. However, testicular tumours have rarely been reported. This report describes a metastatic testicular sex cord-stromal tumour leading to fatal haemorrhage and thrombosis in a captive African lion (Panthera leo). CASE PRESENTATION: During necropsy of a 16-year-old male African lion, the left testicle and spermatic cord were found to be intra-abdominal (cryptorchid), semi-hard and grossly enlarged with multiple pale-yellow masses. Encapsulated haemorrhage was present in the retroperitoneum around the kidneys. Neoplastic thrombosis was found at the renal veins opening into the caudal vena cava. Metastases were observed in the lungs and mediastinal lymph nodes. Histology revealed a poorly differentiated pleomorphic neoplasm comprised of round to polygonal cells and scattered spindle cells with eosinophilic cytoplasm. An immunohistochemistry panel of inhibin-α, Ki-67, human placental alkaline phosphatase, cytokeratin AE1/AE3, cKit, vimentin and S100 was conducted. Positive cytoplasmic immunolabeling was obtained for vimentin and S100. CONCLUSIONS: The gross, microscopic and immunohistochemical findings of the neoplasm were compatible with a poorly differentiated pleomorphic sex cord-stromal tumour. Cause of death was hypovolemic shock from extensive retroperitoneal haemorrhage and neoplastic thrombosis may have contributed to the fatal outcome. To our knowledge, this is the first report of sex cord-stromal tumour in non-domestic felids.

Fatal haemorrhage and neoplastic thrombosis in a captive African lion (Panthera leo) with metastatic testicular sex cord­stromal tumour

Background: The study of neoplasia in wildlife species contributes to the understanding of cancer biology, management practices, and comparative pathology. Higher frequencies of neoplasms among captive non-domestic felids have been reported most commonly in aging individuals. However, testicular tumours have rarely been reported. This report describes a metastatic testicular sex cord­stromal tumour leading to fatal haemorrhage and thrombosis in a captive African lion (Panthera leo). Case presentation: During necropsy of a 16-year-old male African lion, the left testicle and spermatic cord were found to be intra-abdominal (cryptorchid), semi-hard and grossly enlarged with multiple pale-yellow masses. Encapsulated haemorrhage was present in the retroperitoneum around the kidneys. Neoplastic thrombosis was found at the renal veins opening into the caudal vena cava. Metastases were observed in the lungs and mediastinal lymph nodes. Histology revealed a poorly differentiated pleomorphic neoplasm comprised of round to polygonal cells and scattered spindle cells with eosinophilic cytoplasm. An immunohistochemistry panel of inhibin-α, Ki-67, human placental alkaline phosphatase, cytokeratin AE1/AE3, cKit, vimentin and S100 was conducted. Positive cytoplasmic immunolabeling was obtained for vimentin and S100. Conclusions: The gross, microscopic and immunohistochemical findings of the neoplasm were compatible with a poorly differentiated pleomorphic sex cord­stromal tumour. Cause of death was hypovolemic shock from extensive retroperitoneal haemorrhage and neoplastic thrombosis may have contributed to the fatal outcome. To our knowledge, this is the first report of sex cord­stromal tumour in non-domestic felids.

Antecedentes: O estudo da neoplasia em espécies silvestres contribui para a compreensão da biologia do câncer, manejo práticas e patologia comparada. Maiores frequências de neoplasias em felinos não domésticos em cativeiro foram relatados mais comumente em indivíduos idosos. No entanto, tumores testiculares raramente foram relatados. este O relatório descreve um tumor estromal do cordão sexual testicular metastático, levando a hemorragia fatal e trombose em um leão africano em cativeiro (Panthera leo). Apresentação do caso: Durante a necropsia de um leão africano de 16 anos, o testículo esquerdo e o cordão espermático foram encontrado intra-abdominal (criptorquídeo), semi-rígido e grosseiramente aumentado com várias massas amarelo-pálidas. Encapsulado hemorragia estava presente no retroperitônio ao redor dos rins. Trombose neoplásica foi encontrada em as veias renais se abrem para a veia cava caudal. Metástases foram observadas nos pulmões e na linfa mediastinal nós. A histologia revelou uma neoplasia pleomórfica pouco diferenciada composta por células redondas a poligonais e células fusiformes dispersas com citoplasma eosinofílico. Um painel de imuno-histoquímica de inibina-α, Ki-67, humano foram realizadas fosfatase alcalina placentária, citoqueratina AE1 / AE3, cKit, vimentina e S100. Citoplasmático positivo a marcação imunológica foi obtida para vimentina e S100. Conclusões: Os achados macroscópicos, microscópicos e imuno-histoquímicos da neoplasia foram compatíveis com tumor estromal do cordão sexual pleomórfico pouco diferenciado. A causa da morte foi choque hipovolêmico de extensa hemorragia retroperitoneal e trombose neoplásica podem ter contribuído para o desfecho fatal. Para nosso conhecimento, este é o primeiro relato de tumor do cordão sexual estroma em felinos não domésticos.

Evaluation of activity of triclabendazole against Taenia solium metacestode in naturally infected pigs.

OBJECTIVE: To assess the efficacy of triclabendazole (TCBZ) in porcine cysticercosis. METHODS: Eighteen naturally infected cysticercosis pigs were divided into 3 groups of 6 individuals each. The first group was treated orally with TCBZ at a single dose of 30 mg/kg of body weight, the second group was treated orally with oxfendazole at a single dose of 30 mg/kg of body weight and the third group received a placebo (control group). All animals were kept under the same management conditions. The pigs were euthanized 17 wk post-treatment and the number of surviving cysts in muscles was assessed and compared between groups. RESULTS: All pigs treated with oxfendazole had only degenerated cysts in their carcasses. In contrast, TCBZ had very little effect against the parasitic cysts. Cysts from pigs in the TCBZ group looked apparently normal after treatment. However, histological evaluation showed a mild to moderate degree of inflammation. CONCLUSIONS: TCBZ is not an efficacious drug against Taenia solium cysticercosis in swine using a single dose.

The taruca (Hippocamelus antisensis) and the red brocket deer (Mazama americana) as intermediate hosts of Taenia hydatigena in Peru, morphological and molecular evidence.

In the present report metacestodes were collected from the mesentery of a taruca (Hippocamelus antisensis) and from the omentum of a red brocket deer (Mazama americana) in Peru. Various metacestodes parameters, including rostellar hook characteristics, were measured. Molecular analysis was performed to amplify the mitochondrial cytochrome c oxidase subunit 1 gene from metacestode isolates. Metacestodes were identified as T. hydatigena by morphology and molecular methods. This constitutes the first molecular detection of T. hydatigena metacestodes in the taruca and the red brocket deer and demonstrates that these animal species are natural intermediate hosts for this parasite.

Histopathological Aspects and Etiology of Pneumonias in Stranded Marine Mammals from Lima, Peru

This study presents the histopathologic features of pneumonia in stranded marine mammals on the coast of Lima, Peru during the period of May 2003 to December 2008. Lung samples of 24 South American sea lions (Otaria flavescens), four bottlenose dolphins (Tursiops truncatus), one dusky dolphin (Lagenorhynchus obscurus), one Burmeister´s porpoise (Phocoena spinipinnis) and one marine otter (Lontra felina) were fixed in 10% formalin and then processed and stained with haematoxylin and eosin, periodic acid-Shiff (PAS) and trichromic of Masson. From the 31 samples collected only 29 were suitable for microscopic evaluation. The results show a rate of 29/29 pneumonias (100%), five of which were associated to parasites (17%), six of bacteria (21%), four of mixed (parasites and bacteria) (14%) and 14 were of nonspecific cause (48%). The present research indicates that those marine mammals from Lima, Peru are exposed to lungworms, flukes and bacteria that alone or mixed may cause pneumonias, which could be contributed or to be the primary cause of the stranding in these animals.(AU)

Histopathological aspects and etiology of pneumonias in stranded marine mammals from Lima, Peru

Peru during the period of May 2003 to December 2008. Lung samples of 24 South American sea lions (Otaria flavescens), four bottlenose dolphins (Tursiops truncatus), one dusky dolphin (Lagenorhynchus obscurus), one Burmeister´s porpoise (Phocoena spinipinnis) and one marine otter (Lontra felina) were fixed in 10% formalin and then processed and stained with haematoxylin and eosin, periodic acid-Shiff (PAS) and trichromic of Masson. From the 31 samples collected only 29 were suitable for microscopic evaluation. The results show a rate of 29/29 pneumonias (100%), five of which were associated to parasites (17%), six of bacteria (21%), four of mixed (parasites and bacteria) (14%) and 14 were of nonspecific cause (48%). The present research indicates that those marine mammals from Lima, Peru are exposed to lungworms, flukes and bacteria that alone or mixed may cause pneumonias, which could be contributed or to be the primary cause of the stranding in these animals.