Fernando Froner Argenta
Universidade Federal do Rio Grande do Sul
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Parasitology Research | 2017
Lismara Castro do Nascimento; Hilda Fátima de Jesus Pena; Ronaldo Viana Leite Filho; Fernando Froner Argenta; Bruna Farias Alves; Solange Oliveira; Solange Maria Gennari; David Driemeier
Toxoplasmosis is a widely distributed disease that infects birds and mammals, including humans. Acute clinical course of toxoplasmosis is considered to be rare among domestic rabbits (Oryctolagus cuniculus). The aim of this study was to present the first report of fatal acute disease caused by Toxoplasma gondii type BrIII genotype, a typical Brazilian clonal lineage, in a domestic rabbit. T. gondii was identified in histological sections of spleen and liver tissue, and these tissues were also immunohistochemically positive for T. gondii. After the histopathological and immunohistochemical confirmation of T. gondii, the genotype of this pathogen was determined via PCR-RFLP with 11 markers (SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, Apico, and CS3) and via microsatellite (MS) analysis with 15 markers (TUB2, W35, TgMA, B18, B17, M33, IV.1, X1.1, M48, M102, N60, N82, AA, N61, and N83). This study shows that type BrIII genotype, circulating in Brazil in different hosts, can cause acute disease in a naturally infected animal host. The described case also involves the first reported occurrence of the 291 allele for the typing marker TUB2 in a type BrIII strain, emphasizing the genetic diversity of T. gondii in Brazil.
Acta Scientiae Veterinariae | 2018
Fernando Froner Argenta; Paula Reis Pereira; Rafaela Albuquerque Caprioli; Andréia Vielmo; Luciana Sonne; Saulo Petinatti Pavarini; David Driemeier
Background: Testicular neoplasms are common in dogs, and their incidence is higher in older animals, and in cases of cryptorchidism. In general, they are benign and rarely metastasize. The aim of this study is to determine the frequency of testicular neoplasms in dogs in the Departament of Veterinary Pathology of the Universidade Federal do Rio Grande do Sul (SPV-UFGRS) in the period of January 2005 to December 2015. Materials, Methods & Results: Histopathological examination records of dogs conducted from January 2005 to December 2015 on SPV-UFRGS were reviewed searching for cases of testicular neoplasms in dogs. The general data of the dogs were analyzed, such as age, clinical history and clinical signs, when reported according to the requester. The classification of neoplasms in this study followed the histological criteria established by the World Health Organization. In the period studied, 4,764 biopsies were processed from male dogs, 305 (6.4%) of them were diagnosed with testicular neoplasms. The mean age range was 11.1 year-old. In 260 dogs, the neoplasms have affected a single testicle, and in 45, they were bilateral. From 305 dogs, 247 had a single neoplasm, while 58 dogs have developed more than one type of neoplasm, at once, totaling 415 diagnosis of testicular neoplasms. The most prevalent testicular neoplasms were Leydig cell tumor, followed by seminoma, and sertoli cell tumor, representing 50.8%, 35.2% and 14% respectively. Forty-five animals presented bilateral testicular neoplasms single or multiple, totaling 104 diagnoses. Leydig cell tumor was the most frequent bilateral neoplasm. Fifty dogs developed neoplasms in cryptorchid or ectopic testicles, representing 24.4% of cases with reported clinical data. Of these, nine were located in the inguinal region, nine in the subcutaneous, intra-abdominal 12, and in 20 cases the location was not informed. In these cases the mean age range was 9.5 year-old. Clinical signs of hyperestrogenism were reported in 4.9% of cases and histological changes of malignancy were reported in 5.5% of all diagnoses. Discussion: The frequency of testicular neoplasms in dogs in this study, and the average age, were similar to several studies. Leydig cell tumor, seminoma and sertoli cell tumor are the most common testicular neoplasms diagnosed in this paper, as described in some studies. Data relating to bilateral and multiple neoplasms cases are similar to several researchers. The combination of seminoma with Leydig cell tumor was the most frequent in this study, similar to the literature. The occurrence of cryptorchidism in dogs was described in 24.4% of cases while similar studies reported frequency of 4.5% to 56.3%. Histological changes with malignancy characteristics were described in 5.5% of all cases of this study, and were predominantly characterized by invasion of neoplasic cells into the lymphatic and blood vessels, of these, 95.6% were seminomas and 4.4% sertoliomas. This information agrees with researchers that reported that metastases occur in less than 15% of sertoli cell tumor or seminomas. Clinical manifestations of feminization were infrequent in cases of testicular neoplasms in dogs of this paper, and the sertolioma is the neoplasm most commonly associated with manifestations of hyperestrogenism. As described in literature, over 50% of dogs with sertoli cell tumor show signs of feminization, but most of the cases are asymptomatic, and often an incidental finding at the time of physical examination. Background: Testicular neoplasms are common in dogs, and their incidence is higher in older animals, and in cases of cryptorchidism. In general, they are benign and rarely metastasize. The aim of this study is to determine the frequency of testicular neoplasms in dogs in the Departament of Veterinary Pathology of the Universidade Federal do Rio Grande do Sul (SPV-UFGRS) in the period of January 2005 to December 2015. Materials, Methods & Results: Histopathological examination records of dogs conducted from January 2005 to December 2015 on SPV-UFRGS were reviewed searching for cases of testicular neoplasms in dogs. The general data of the dogs were analyzed, such as age, clinical history and clinical signs, when reported according to the requester. The classification of neoplasms in this study followed the histological criteria established by the World Health Organization. In the period studied, 4,764 biopsies were processed from male dogs, 305 (6.4%) of them were diagnosed with testicular neoplasms. The mean age range was 11.1 year-old. In 260 dogs, the neoplasms have affected a single testicle, and in 45, they were bilateral. From 305 dogs, 247 had a single neoplasm, while 58 dogs have developed more than one type of neoplasm, at once, totaling 415 diagnosis of testicular neoplasms. The most prevalent testicular neoplasms were Leydig cell tumor, followed by seminoma, and sertoli cell tumor, representing 50.8%, 35.2% and 14% respectively. Forty-five animals presented bilateral testicular neoplasms single or multiple, totaling 104 diagnoses. Leydig cell tumor was the most frequent bilateral neoplasm. Fifty dogs developed neoplasms in cryptorchid or ectopic testicles, representing 24.4% of cases with reported clinical data. Of these, nine were located in the inguinal region, nine in the subcutaneous, intra-abdominal 12, and in 20 cases the location was not informed. In these cases the mean age range was 9.5 year-old. Clinical signs of hyperestrogenism were reported in 4.9% of cases and histological changes of malignancy were reported in 5.5% of all diagnoses. Discussion: The frequency of testicular neoplasms in dogs in this study, and the average age, were similar to several studies. Leydig cell tumor, seminoma and sertoli cell tumor are the most common testicular neoplasms diagnosed in this paper, as described in some studies. Data relating to bilateral and multiple neoplasms cases are similar to several researchers. The combination of seminoma with Leydig cell tumor was the most frequent in this study, similar to the literature. The occurrence of cryptorchidism in dogs was described in 24.4% of cases while similar studies reported frequency of 4.5% to 56.3%. Histological changes with malignancy characteristics were described in 5.5% of all cases of this study, and were predominantly characterized by invasion of neoplasic cells into the lymphatic and blood vessels, of these, 95.6% were seminomas and 4.4% sertoliomas. This information agrees with researchers that reported that metastases occur in less than 15% of sertoli cell tumor or seminomas. Clinical manifestations of feminization were infrequent in cases of testicular neoplasms in dogs of this paper, and the sertolioma is the neoplasm most commonly associated with manifestations of hyperestrogenism. As described in literature, over 50% of dogs with sertoli cell tumor show signs of feminization, but most of the cases are asymptomatic, and often an incidental finding at the time of physical examination.
Acta Scientiae Veterinariae | 2017
Fernando Froner Argenta; Sissy Hobbhahn; Maria Inês Witz; Luiz Cezar Bello Fallavena; Anamaria Telles Esmeraldino
Background: Lobular dissecting hepatitis (LDH) is a rare condition of unknown etiology occurring in individuals or in litters of young dogs from some breeds, having poor prognosis and short survival time. Clinically, ascites, weight loss, anorexia, diarrhea and acquired portosystemic shunts are present. Hepatic encephalopathy may also occur. Biochemical blood tests usually show elevated ALT levels. Macroscopically, the liver shows changes in volume, color and regeneration nodules. Histologically, dissection of the parenchyma by connective tissue proliferation leads to disorganization of the liver architecture. The aim of this article is report LDH in two Golden Retriever dogs genetically unrelated. Cases: Two dogs genetically unrelated and of different owners - Golden Retriever breed - were referred to the Veterinary Medical Teaching Hospital of the Universidade Luterana do Brasil (ULBRA). The first case was a female with 17 months of age and the second, brought to examination one year later, was a male with nine months of age. The clinical signs, in both animals were similar, consisting in intense prostration, inapetence, caquexia and ascites for approximately two weeks. The female dog presented also ataxia, convulsion and diarrhea. Blood examination showed, for both dogs, arregenerative anemia, normal levels of alanine aminotransferase (ALT) and elevated levels of alkaline phosphatase. Total serum protein and albumin were also reduced. Both dogs were euthanized due to their critical condition. The necropsy showed similar lesions in both animals: approximately one liter of a free red colored fluid was observed in the abdominal cavity and hepatic changes consisting in pale green color, smooth surface, firm consistence, yellowish nodules at the surface and tissue proliferation at the margins. There was also congestion of the abdominal visceral veins (portal shunts). Histopathological examination showed, for both dogs, interstitial diffuse fibrosis causing dissection of the parenchyma and isolating hepatocytes in small groups, marked cholestasis and sinusoidal infiltration of inflammatory cells (mainly lymphocytes and plasma cells). Discussion: Lobular dissecting hepatitis is a rare form of hepatic cirrhosis, being unique only to dogs. Some breeds including German Shepherd, Poodle, Rottweiler, Cocker Spaniel and Golden Retriever are considered susceptible to the disease. The clinical signs, age, breed and macroscopic and microscopic lesions presented by the two dogs were consistent with LDH. In this disease, serum biochemistry analyses generally show hypoalbuminemia and increased levels of hepatic enzymes, mainly the ALT. In both animals herein described, albumin levels were decreased, but ALT levels were normal, indicating that a suspicion of this disease should not be discarded in similar cases. ALT levels, as well as of other hepatic enzymes, may not reflect the severity of chronic hepatopathies like LDH, in which the producer cells of this enzyme are being destroyed. These two animals, in spite of pertaining to the same breed, did not presented any genetic relationship, and were owned by different persons. The disease may have a great number of possible etiologies and historical data from the two dogs herein described did not indicated any relevant aspect which could be implicated as a cause of the condition. As affected animals are generally referred to a veterinary consultation in an advanced condition, the cause is difficult to be determined.
Acta Scientiae Veterinariae | 2017
Paula Reis Pereira; Fernando Froner Argenta; Veronica Machado Rolim; Eduardo Conceição de Oliveira; Luciana Sonne; Saulo Petinatti Pavarini; David Driemeier
Background: Aelurostrongylus abstrusus is a lungworm of cats with worldwide distribution. The adult forms of this parasite live in terminal bronchioles and alveoli, and can cause an asymptomatic disease or predominantly respiratory clinical signs, which can be occasionally cause of death. The aim of this study is to describe the epidemiological and pathological findings of infection by A. abstrusus through a necropsy retrospective study. Materials, Methods & Results: the necropsy records from the Department of Veterinary Pathology of the Universidade Federal do Rio Grande do Sul were recovered and cats diagnosed with lungworm by Aelurostrongylus abstrusus were selected since January 1998 until December 2015. General data, such as age, sex, breed, clinical signs, and macroscopic lesions, were analyzed and compiled. The histological slides were reviewed by optical microscopy and detailed the microscopic aspects. In this study, were identified 22 cats with varying degrees of lungworm by A. abstrusus, and in 45.5% of the cases, this was the cause of death. Most part of the cats were mixed breed (19/22), and there were no sex predisposition. The age of the cats ranged from four months to 11 years old, and the most frequent age group was three to six years, with nine cases reported. In 37.5% of the cases were reported respiratory clinical signs, such as dyspnea and nasal discharge, and in 62.5%, clinical signs were not specific. The gross findings of the lungs ranged from reddish, or yellowish or white areas, and presence of multiples small, firm, and whitish nodules, measuring more than two centimeters in diameter, with multifocal distribution in the lung surface. Histologically, there was varied amount of parasites in different stages in the alveolar spaces, associated with the inflammatory infiltrate composed of lymphocytes, plasma cells, macrophages, neutrophils and occasional multinucleated giant cells, and hypertrophy and hyperplasia of the pulmonary smooth muscle and the wall of the arteries. Discussion: Aelurostrongylus abstrusus is the principal parasite of lung of cats, with worldwide distribution. In this study, we observed that 40.9% of cases were reported as of 2012, and may be due to a larger propagation of definitive intermediate and paratenic hosts, climate changes and/or the increase of rearing cats, and the consequent increase of hospital routine. Agreeing with the others authors, there is no sex predilection, but differ in the age group, in to the present study, the most frequent age group was between “3 to 6 years” of age (52.9%). The gross findings observed were similar to those described by other authors. Histologically was observed varied amount of parasites, and the degree of inflammatory infiltrate were very similar, but with a slight difference in discrete infiltration (36.4%). Others researchers have identified predominantly severe inflammatory infiltrate (57.9%). Hypertrophy and hyperplasia of pulmonary smooth muscle and the wall of the arteries was moderate (50%), however, in previous studies were severe. The diagnosis of aelurostrongilosis through parasitological tests have proven the occurence this lung parasite in the study region, highlighting the importance of this study by adding epidemiological and pathological data on the disease.
Pesquisa Veterinaria Brasileira | 2015
Welden Panziera; Maiara Aline Gonçalves; Marina Paula Lorenzett; Pedro Damboriarena; Fernando Froner Argenta; Cláudio João Mourão Laisse; Saulo Petinatti Pavarini; David Driemeier
Poisoning by the toxic species of Baccharis is an important cause of death in farm animals. Baccharis coridifolia and Baccharis megapotamica are the most common and most important of this genus. Epidemiological, clinical and pathological aspects of a natural outbreak of intoxication by Baccharis megapotamica var. weiriiare described in goats. Eleven young goats from a herd of 152 goats were affected by an acute fatal disease. The cases occurred in a small farm in the municipality of Viamao, State of Rio Grande do Sul, southern Brazil. Large patches of blooming Baccharis megapotamica var. weirii were observed in the pastures where the goats were held, especially in wet and flooded spots. Affected goats were between six months to one year old and all showed signs including apathy, anorexia, weakness, diarrhea, dehydration, abdominal pain, bloat, decubitus and death. The clinical course was 12-24 hours. Three out of the eleven goats dead from the toxicosis were necropsied. Changes present in all necropsied goats included dehydration, liquid contents in the rumen, reddening, erosions and ulcers in the mucosae of the forestomachs, abomasum, and intestine. One goat had marked hemorrhage of mesenteric lymph nodes. Histological lesions of all animals included hyperemia as well as degenerative, necrotic, and ulcerative changes in the epithelial lining of rumen, reticulum, and omasum. Mucosae of the abomasum and of some sections of small and large intestines were also affected. Necrosis of lymphoid tissue was observed in mesenteric lymph nodes and in the lymphoid aggregates in intestine and in the follicles of spleen.
Acta Scientiae Veterinariae | 2017
Paula Reis Pereira; Fernando Froner Argenta; Veronica Machado Rolim; Eduardo Conceição de Oliveira; Luciana Sonne; Saulo Petinatti Pavarini; David Driemeier
Revista de Iniciação Científica da ULBRA | 2011
Renata Sesterhenn; Diego Tramontini; Fernando Froner Argenta; Celso Pianta; Anamaria Telles Esmeraldino; Luiz Cesar Bello Fallavena
Semina-ciencias Agrarias | 2018
Fernando Froner Argenta; M. E. Hammerschmitt; Matheus de Oliveira Reis; Raquel Aparecida Sales da Cruz; Cíntia de Lorenzo; Luciana Sonne; David Driemeier; Saulo Petinatti Pavarini
Pesquisa Veterinaria Brasileira | 2018
Fernando Froner Argenta; Veronica Machado Rolim; Cíntia de Lorenzo; Gustavo Geraldo Medina Snel; Saulo Petinatti Pavarini; Luciana Sonne; David Driemeier
Pesquisa Veterinaria Brasileira | 2018
Fernando Froner Argenta; Saulo Petinatti Pavarini; David Driemeier; Luciana Sonne