David Driemeier - Academia.edu (original) (raw)
Papers by David Driemeier
Acta Scientiae Veterinariae, Aug 17, 2019
Background: Anaplastic carcinoma of the mammary gland is considered a highly invasive and maligna... more Background: Anaplastic carcinoma of the mammary gland is considered a highly invasive and malignant neoplasia, which usually leads to neoplastic thrombosis and epidermal ulceration due to invasiveness of lymphatic vessels by tumor emboli. Loss of epidermal barrier predisposes to secondary bacterial infection, mainly by commensal bacteria of the skin, and septicemia can be observed in cases of systemic dissemination. Neoplastic emboli and septic thrombi can lead to vascular obstruction, which can predispose to infarction in multiple organs. The aim of this case report is to describe a case of hemorrhagic stroke in a dog with anaplastic carcinoma of the mammary gland. Case: A 12-year-old, mixed breed, female spayed canine presented with mammary tumor with plaque formation, associated with skin ulceration which extended to the medial region of pelvic limbs. The animal also displayed neurologic clinical signs characterized by stupor, opisthotonos and apathy. Due to poor prognosis, the canine was euthanized and submitted to necropsy. During external examination, the animal was in a good body condition, had moderately pale mucosae, and it was noted a nodular plaque in the abdominal ventral area extending from thoracic to inguinal mammary gland. The mass was firm and white, extensively ulcerated, and extending from the thoracic to inguinal mammary gland. There was a well circumscribed area of infarction in the spleen and kidney. In the cerebral cortex it was observed an extensive area of hemorrhage with adhered blood clot from frontal to temporal lobe. There were multiple well circumscribed, firm, and white areas in the myocardium. Histologically, the neoplastic proliferation was composed by epithelial cells with high pleomorphism, features of malignancy, and no delimitations, leading to the diagnosis of anaplastic carcinoma of the mammary gland. Admixed with tumor cells there were multiple areas of hemorrhage, necrosis and thrombosis. In the cerebral cortex there was a focally extensive area of hemorrhage, multifocal thrombosis, abundant amount of gitter cells, and moderate perivascular inflammatory infiltrate of lymphocytes. There was neoplastic infiltrate in the bladder, adrenal glands, and lungs. There were multiple areas of necrosis and thrombosis in spleen and heart. Bacterial examination was performed in fragments of cerebral cortex and kidney, and Staphylococcus pseudintermedius was isolated. Discussion: Anaplastic carcinoma of the mammary gland has an epithelial origin and is considered the most malignant neoplasm with worst prognosis due to its characteristic of high cellular pleomorphism and the ability of invasiveness of vessels and adjacent tissues. Therapeutic options are scarce and palliative, and surgical removal is not indicated. Dermal ulceration usually is infected by opportunistic bacteria that can lead to inflammation and pain, and treatment in these cases is focused on pain management with analgesics. The bacterial infection can evolve to septicemia with decrease of endogenous anticoagulants and consequent blood hypercoagulability. Moreover, studies demonstrate the higher risk of clotting abnormalities when associated to progression of mammary carcinomas, which includes anaplastic carcinoma of the mammary gland. In this study, two causes which may have led to thromboembolism and cerebral hemorrhage are discussed: septicemia after invasion of lymphatic vessels by the anaplastic carcinoma or hypercoagulability caused by the systemic neoplasia, which could have reduce the blood flow to vessels of the cerebral cortex.
Ticks and Tick-borne Diseases, Jul 1, 2020
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Ciencia Rural, 2017
Causes of bird losses recorded in a captive-bred wild bird flock between 2011 and 2015.
Parasitology Research, Jun 30, 2021
Naegleria fowleri, a free-living and thermophilic ameba, is the etiological agent of primary ameb... more Naegleria fowleri, a free-living and thermophilic ameba, is the etiological agent of primary amebic meningoencephalitis (PAM). PAM is a rare and highly fatal neurologic disease in humans, and has been rarely documented in animal species. This report describes the pathological and etiological findings of a fatal case of N. fowleri-associated meningoencephalitis in a cow in Southern Brazil. Microscopic findings were consistent with severe, multifocal, hemorrhagic, and necrosuppurative meningoencephalitis associated with a large number of amebic trophozoites compatible with N. fowleri. Brain samples subjected to molecular assays generated a 315 bp fragment, which presented 99% identity with a N. fowleri sequence previously deposited in GenBank. This is the first study reporting the molecular detection of N. fowleri in a case of cattle meningoencephalitis in Latin America, and the obtained sequence represents the first GenBank deposit of N. fowleri identified in Brazil to this day. Additionally, the case reported is the second occurrence of N. fowleri-associated disease in the same city, drawing attention to the local importance of infection by this ameba and potential risk for human infections.
Brazilian Journal of Microbiology, May 22, 2021
Porcine encephalomyelitis can be associated with many etiologies, including viral agents, such as... more Porcine encephalomyelitis can be associated with many etiologies, including viral agents, such as Porcine teschovirus (PTV), Porcine sapelovirus (PSV), and Porcine astrovirus (PoAstV). In this study, we investigated the presence of these viruses in a neurological disease outbreak in a swine farm in Southern Brazil. The piglet production farm unity had 1200 weaning piglets, and 40 piglets with neurological signs such as motor incoordination, paresis, and paralysis of hind limbs, with an evolution time of approximately 4 days. Among these, 10 piglets were submitted to postmortem examination. Gross lesions were restricted to a mild enlargement of the nerve roots and ganglia of spinal cord segments. The microscopic lesions were characterized by nonsuppurative encephalomyelitis and ganglioneuritis with evident neuronal degeneration and necrosis. Samples of the central nervous system (CNS), cerebrospinal fluid, and feces were collected and submitted to molecular analysis. PTV was identified in all samples of the CNS, while eight of the piglets were also positive for PSV, and seven were positive for Porcine enterovirus (EV-G). PoAstV was identified in a pool of feces of healthy animals used as controls. This study demonstrates the occurrence of encephalomyelitis associated with PTV on a swine farm in Southern Brazil, as well as the presence of other viruses such as PSV, EV-G, and PoAstV in the swineherd. Sequences of the fragments that were previously amplified by PCR showed a high similarity to PTV 6. Herein, we describe the first case report of severe swine polioencephalomyelitis associated with PTV in South America.
Ciencia Rural, 2021
Salmonellosis is a bacterial disease that affects several domestic animal species, and is commonl... more Salmonellosis is a bacterial disease that affects several domestic animal species, and is commonly diagnosed in cattle, horses, and pigs. This study aimed to describe the epidemiological and pathological findings of eleven cases of enteric salmonellosis and two cases of salmonellosis with pulmonary involvement in cattle in Rio Grande do Sul State, Brazil. Clinical signs included fever, yellow diarrhea, sometimes with blood streaks, and dyspnea, with a clinical course ranging from 1 to 30 days. Eight cases occurred as outbreaks, whereas five cases occurred individually. Risk factors included inadequate handling practices, such as overcrowded facilities and comorbidities, including anaplasmosis. The main gross finding of the enteric presentation was fibrinonecrotic enterocolitis, occasionally associated with button ulcers, mesenteric lymphadenomegaly, splenomegaly, cholecystitis and hepatomegaly. In addition, one steer with a chronic clinical progression presented severe segmental thickening of the ileum, associated with intestinal rupture and peritonitis. In the respiratory system, the main findings were reddened, non-collapsed lungs, with multifocal areas of atelectasis. The main microscopic findings were observed in the small and large intestines, and these were characterized by severe necrosis and mucosal ulceration, associated with marked inflammatory infiltrate of neutrophils and fibrin deposition intermixed by rod-shaped bacterial aggregates, and fibrosis, as well as interstitial pneumonia. Seven cases yielded positive bacterial cultures for Salmonella spp. and three serovars, namely Typhimurium, Dublin, and Panama were identified. All cases exhibited immunolabeling for Salmonella spp. using immunohistochemistry.
Brazilian Journal of Microbiology, Apr 27, 2022
Visna-maedi is a multisystemic and progressive inflammatory disease caused by a non-oncogenic ret... more Visna-maedi is a multisystemic and progressive inflammatory disease caused by a non-oncogenic retrovirus (Visna-maedi virus, VMV). An outbreak of visna-maedi occurred in Southern Brazil in sheep with clinical signs of blindness and stumbling gait. At post-mortem examination, all animals had similar lesions, including heavy non-collapsed lungs and multifocal yellow areas in the cerebral white matter, affecting mainly the periventricular region. These lesions corresponded histologically to lymphocytic interstitial pneumonia and histiocytic periventricular encephalitis surrounding areas of necrosis, in addition to significant demyelination in the brain. Serology was performed in all the sheep from the flock and 14% were seropositive for VMV. The presence of VMV was confirmed through PCR and partial sequencing of the 5′LTR. Sequencing demonstrated that the virus had 89.7 to 90.0% of nucleotide identity with VMV strains reported in the USA. This is the first description of clinical disease related to VMV in Brazil leading to economic losses. This study calls for the need to implement control measures to prevent the spread of small ruminant lentiviruses in Brazil.
Revista Brasileira De Medicina Veterinaria, Sep 15, 2016
Occurrence of anti-Neospora caninum antibodies in dairy cattle in the western of Santa Catarina, ... more Occurrence of anti-Neospora caninum antibodies in dairy cattle in the western of Santa Catarina, Brazil.] Ocorrência de anticorpos anti-Neospora caninum em bovinos leiteiros no oeste do estado de Santa Catarina, Brasil.
Acta Scientiae Veterinariae, Jun 27, 2017
Background: Infectious diseases have expanded their host and geographic ranges, increasing impact... more Background: Infectious diseases have expanded their host and geographic ranges, increasing impacts on both human and animal health. Mycoplasma gallisepticum usually causes avian chronic respiratory conditions and Histomonas meleagridis infects the cecum and the liver of poultry. Although these diseases have been reported in several bird species, information associated with their prevalence and impact in local flocks of ornamental birds is scarce. This communication describes severe outbreaks of mycoplasmosis and histomoniasis that affected a southern Brazilian commercial flock of ornamental birds. Case: The outbreaks occurred in an ornamental bird flock that contained 2,340 birds from 39 different species, distributed mostly in the orders Galliformes, Anseriformes, and Psittaciformes. Mycoplasma gallisepticum affected 12 chukar partridges, 12 Indian peacocks, 19 ornamental chickens and 46 individuals of 4 species of pheasant. The disease cases were distributed between April and July 2015. A total of 36 birds died due to the disease' complications and most surviving birds suffered from severe ocular sequels, which determined their subsequent culling, despite attempts of different treatment protocols. The main signs included coughing, sneezing, infraorbital swelling, wasting, and death which were mostly associated with caseous sinusitis. Affected birds had positive samples when stained with anti-Mycoplasma gallisepticum immunohistochemistry and tested by Mycoplasma gallisepticum-Polymerase Chain Reaction. The application of 2 doses of a Mycoplasma gallisepticum vaccine in early 2016 to all the Galliformes in the flock reduced the annual prevalence to 4 clinical cases. Histomoniasis affected and killed 19 out of 27 chukar partridges that were being kept with ring-necked pheasants in the same enclosure. The disease occurred between September and December 2016 and a high prevalence of Heterakis gallinarum was detected in the flock. The main findings included apathy and death linked to hepatic and cecal necrosis. Admixed in the necrotic areas, there were numerous round to oval, eosinophilic, protozoal trophozoites of 15-20 µm in diameter, occasionally containing a 3-5 µm centrally located basophilic nucleus (histomonads) surrounded by a clear halo. Anthelmintic dosing, exchanging and liming the bedding material of the enclosures, and keeping the remaining partridges in an aerial aviary with a wire mesh floor prevented additional cases of histomoniasis. Discussion: In Brazil, as in other countries, the sanitary management practices applied in commercial chicken production reached high levels of technification. However, this is not the case in ornamental bird breeding systems, which may still suffer the impacts of diseases that are practically extinct in industrial chicken flocks. For both diseases, diagnosis was based on typical clinical signs and detection of the pathogens in association with characteristic pathological findings. The occurrence of mycoplasmosis and histomoniasis was associated with improper management practices at the farm; the main risk factors observed were a high turnover of birds, the absence of quarantine, the absence of basic health care, overcrowding and poor hygiene. The prevention of further cases of both diseases was mostly established with the application of basic sanitary measures, including vaccination and anthelmintic dosing, for mycoplasmosis and histomoniasis respectively. This report alerts bird keepers and avian veterinarians of the importance of establishing proper sanitary management in local ornamental bird flocks. Because some of the ornamental bird species that have been commercially propagated worldwide may be included in the list of threatened species, the findings described here also show that simple health care may promote the fight against extinctions.
Tropical Animal Health and Production, Apr 17, 2019
Enzootic nasal tumor (ENT) is a contagious neoplasm associated with enzootic nasal tumor virus (E... more Enzootic nasal tumor (ENT) is a contagious neoplasm associated with enzootic nasal tumor virus (ENTV), which may induce disease in sheep (ENTV-1) and goats (ENTV-2). This study aimed to describe the occurrence of ENT in two Texel sheep (Ovis aries) from a 75-sheep flock, located in the city of Gravataí, southern Brazil. Animals used to be purchased from different origins, and no specific tests for disease monitoring or quarantine procedure were performed. Affected animals presented respiratory distress, anorexia with severe weight loss, and mucopurulent unilateral nasal discharge. Necropsy was performed in both animals and nasal cavity masses were observed. Histopathological analysis demonstrated an epithelial neoplasm compatible with nasal adenocarcinoma. PCR using a protocol that amplifies a 591 bp sequence of 5'LTR-gag region of ENTV1 was performed followed by DNA sequencing. Both samples were positive, and the sequences obtained presented highest identity (97%) with ENTV strain TN28 (GenBank accession number MH899613) detected in a Texel sheep from Scotland. This is the first report of ENTV-1 leading to enzootic nasal tumor in sheep in Latin America, which confirms the presence of the retrovirus in sheep flocks in the Brazilian territory.
Revista Brasileira De Parasitologia Veterinaria, 2022
This is an Open Access article distributed under the terms of the Creative Commons Attribution Li... more This is an Open Access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Outbreak of toxoplasmosis associated with muscular lesions in finishing pigs caused by an atypical Toxoplasma gondii genotype Surto de toxoplasmose associado a lesões musculares em suínos de terminação causado por um genótipo atípico de T. gondii
Pesquisa Veterinaria Brasileira, 2022
RESUMO.-[Osteoporose em suínos.] Quarenta e seis suínos apresentaram fraqueza muscular, paresia e... more RESUMO.-[Osteoporose em suínos.] Quarenta e seis suínos apresentaram fraqueza muscular, paresia e paralisia de membros pélvicos, perda de peso, decúbito lateral e morte, com um curso clínico de 7 a 10 dias. Dois suínos foram submetidos a necropsia e exibiram fragilidade óssea, formação de calo ósseo, e múltiplas fraturas em membros, costelas e vértebras. Microscopicamente notou-se difusamente um marcado decréscimo na espessura e número de trabéculas ósseas. Essas estavam desconexas, com uma aparência de flutuação, enquanto o córtex dos ossos longos estava afinado, com um aumento da porosidade pela dilatação dos canais de Haversian, erosão endosteal e diminuição da atividade osteoblástica. Espectrofotometria por chama foi realizada em amostras de fígado, e revelou um excesso de zinco (>2300ppm) e deficiência de cobre (<33.1ppm). Neste trabalho, apresentamos a primeira descrição patológica de um surto de osteoporose em suínos, além de fornecer uma breve revisão de doenças metabólicas em suínos.
Pesquisa Veterinaria Brasileira, 2021
RESUMO.-[Causas de morte em ovinos no Sul do Brasil: análise de 523 casos (2004-2019).] O aumento... more RESUMO.-[Causas de morte em ovinos no Sul do Brasil: análise de 523 casos (2004-2019).] O aumento da comercialização de produtos ovinos requer um aumento equivalente na sanidade do rebanho e uma rápida identificação de doenças. Os dados sobre as causas de morte em ovinos foram revisados no banco de dados do Setor de Patologia Veterinária da Universidade Federal do Rio Grande do Sul, entre janeiro de 2004 e dezembro de 2019. Aspectos epidemiológicos, como raça, sexo e idade, além das características clínicas e patológicas, foram compilados. Nesse período, foram avaliados tecidos de 523 ovinos, em que o diagnóstico conclusivo foi obtido em 457 (87%) dos casos. A grande maioria dos ovinos era da mesorregião metropolitana de Porto Alegre. A raça mais comum foi Texel 171/523 (33%). De todos os diagnósticos conclusivos, 158/457 (35%) corresponderam a doenças infecciosas não-parasitárias, 117/457 (26%) foram causadas por doenças tóxicas, 95/457 (21%) doenças infecciosas parasitárias, 42/457 (9%) foram incluídos na categoria nutricional e metabólica, 38/457 (8%) foram classificadas na categoria "outros", e 7/457 (1,5%) eram defeitos congênitos. A faixa etária das ovelhas incluídas neste estudo foi de um dia a sete anos de idade. Entre os casos com diagnóstico conclusivo, a principal causa de óbito foi hemoncose com 83/457 (18%) dos casos, seguida de pneumonia 29/457 (6%), intoxicação por Baccharis sp. 25/457 (5%), e infecção pelo vírus da língua azul 22/457 (5%).
Journal of Comparative Pathology
Brazilian Journal of Microbiology
Ciencia Rural, 2021
Cardiac malformations are reported to be relatively rare in bovine species, with ventricular sept... more Cardiac malformations are reported to be relatively rare in bovine species, with ventricular septal defects being the most common abnormality observed predominantly in young calves. This report aims to describe the cardiac malformations observed in bovids and review the literature related to those malformations in this species. The necropsy reports of 1,783 bovids were reviewed, and 0.4% were diagnosed with a cardiac congenital defect. The most common cardiac congenital malformation detected in this study was ventricular septal defect, observed alone or associated with other anomalies (in one case, as part of tetralogy of Fallot); followed by atrial septal defect, also alone or with other cardiac malformations. Secondary findings in the lungs and liver were observed in 75% of all cases. Histologic cardiac lesions were identified in 25% of all cases, characterized mainly by fibrosis. Other congenital malformations in different organs were observed in 25% of the cases. Considering the importance of cardiac congenital malformations observed in this study, these conditions should be considered as a differential diagnosis for calves who died with no specific clinical signs. Furthermore, macroscopic evaluation is crucial for the diagnosis of cardiac congenital malformations.
Ciência Rural, 2021
ABSTRACT: Salmonellosis is a bacterial disease that affects several domestic animal species, and ... more ABSTRACT: Salmonellosis is a bacterial disease that affects several domestic animal species, and is commonly diagnosed in cattle, horses, and pigs. This study aimed to describe the epidemiological and pathological findings of eleven cases of enteric salmonellosis and two cases of salmonellosis with pulmonary involvement in cattle in Rio Grande do Sul State, Brazil. Clinical signs included fever, yellow diarrhea, sometimes with blood streaks, and dyspnea, with a clinical course ranging from 1 to 30 days. Eight cases occurred as outbreaks, whereas five cases occurred individually. Risk factors included inadequate handling practices, such as overcrowded facilities and comorbidities, including anaplasmosis. The main gross finding of the enteric presentation was fibrinonecrotic enterocolitis, occasionally associated with button ulcers, mesenteric lymphadenomegaly, splenomegaly, cholecystitis and hepatomegaly. In addition, one steer with a chronic clinical progression presented severe seg...
Ciência Rural, 2018
ABSTRACT: In this work, we describe an unusual case of fibrinous pleuropneumonia caused by Pasteu... more ABSTRACT: In this work, we describe an unusual case of fibrinous pleuropneumonia caused by Pasteurella multocida associated with generalized lymphadenomegaly in a bovine. The animal had a one-month history of generalized superficial lymphadenomegaly that progressed to anorexia and submandibular oedema, resulting in spontaneous death. At necropsy, the parenchyma of the lymph nodes and multiple organs was obliterated by a dense proliferation of round neoplastic cells (lymphoma). Additionally, the neoplasm presented multifocal areas of haemorrhage and necrosis, characteristic of lymphoma. The parietal and visceral pleura and parietal pericardium were enlarged and covered diffusely with large amounts of a yellowish fibrillary material. The lungs were mildly enlarged, non-collapsed, and firm and exhibited interlobular septae that were thickened with a gelatinous material. Histopathological examination showed that the parietal and visceral pleura were enlarged due to a diffuse and severe ...
Ciência Rural, 2021
ABSTRACT: Cardiac malformations are reported to be relatively rare in bovine species, with ventri... more ABSTRACT: Cardiac malformations are reported to be relatively rare in bovine species, with ventricular septal defects being the most common abnormality observed predominantly in young calves. This report aims to describe the cardiac malformations observed in bovids and review the literature related to those malformations in this species. The necropsy reports of 1,783 bovids were reviewed, and 0.4% were diagnosed with a cardiac congenital defect. The most common cardiac congenital malformation detected in this study was ventricular septal defect, observed alone or associated with other anomalies (in one case, as part of tetralogy of Fallot); followed by atrial septal defect, also alone or with other cardiac malformations. Secondary findings in the lungs and liver were observed in 75% of all cases. Histologic cardiac lesions were identified in 25% of all cases, characterized mainly by fibrosis. Other congenital malformations in different organs were observed in 25% of the cases. Consi...
Acta Scientiae Veterinariae, Aug 17, 2019
Background: Anaplastic carcinoma of the mammary gland is considered a highly invasive and maligna... more Background: Anaplastic carcinoma of the mammary gland is considered a highly invasive and malignant neoplasia, which usually leads to neoplastic thrombosis and epidermal ulceration due to invasiveness of lymphatic vessels by tumor emboli. Loss of epidermal barrier predisposes to secondary bacterial infection, mainly by commensal bacteria of the skin, and septicemia can be observed in cases of systemic dissemination. Neoplastic emboli and septic thrombi can lead to vascular obstruction, which can predispose to infarction in multiple organs. The aim of this case report is to describe a case of hemorrhagic stroke in a dog with anaplastic carcinoma of the mammary gland. Case: A 12-year-old, mixed breed, female spayed canine presented with mammary tumor with plaque formation, associated with skin ulceration which extended to the medial region of pelvic limbs. The animal also displayed neurologic clinical signs characterized by stupor, opisthotonos and apathy. Due to poor prognosis, the canine was euthanized and submitted to necropsy. During external examination, the animal was in a good body condition, had moderately pale mucosae, and it was noted a nodular plaque in the abdominal ventral area extending from thoracic to inguinal mammary gland. The mass was firm and white, extensively ulcerated, and extending from the thoracic to inguinal mammary gland. There was a well circumscribed area of infarction in the spleen and kidney. In the cerebral cortex it was observed an extensive area of hemorrhage with adhered blood clot from frontal to temporal lobe. There were multiple well circumscribed, firm, and white areas in the myocardium. Histologically, the neoplastic proliferation was composed by epithelial cells with high pleomorphism, features of malignancy, and no delimitations, leading to the diagnosis of anaplastic carcinoma of the mammary gland. Admixed with tumor cells there were multiple areas of hemorrhage, necrosis and thrombosis. In the cerebral cortex there was a focally extensive area of hemorrhage, multifocal thrombosis, abundant amount of gitter cells, and moderate perivascular inflammatory infiltrate of lymphocytes. There was neoplastic infiltrate in the bladder, adrenal glands, and lungs. There were multiple areas of necrosis and thrombosis in spleen and heart. Bacterial examination was performed in fragments of cerebral cortex and kidney, and Staphylococcus pseudintermedius was isolated. Discussion: Anaplastic carcinoma of the mammary gland has an epithelial origin and is considered the most malignant neoplasm with worst prognosis due to its characteristic of high cellular pleomorphism and the ability of invasiveness of vessels and adjacent tissues. Therapeutic options are scarce and palliative, and surgical removal is not indicated. Dermal ulceration usually is infected by opportunistic bacteria that can lead to inflammation and pain, and treatment in these cases is focused on pain management with analgesics. The bacterial infection can evolve to septicemia with decrease of endogenous anticoagulants and consequent blood hypercoagulability. Moreover, studies demonstrate the higher risk of clotting abnormalities when associated to progression of mammary carcinomas, which includes anaplastic carcinoma of the mammary gland. In this study, two causes which may have led to thromboembolism and cerebral hemorrhage are discussed: septicemia after invasion of lymphatic vessels by the anaplastic carcinoma or hypercoagulability caused by the systemic neoplasia, which could have reduce the blood flow to vessels of the cerebral cortex.
Ticks and Tick-borne Diseases, Jul 1, 2020
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Ciencia Rural, 2017
Causes of bird losses recorded in a captive-bred wild bird flock between 2011 and 2015.
Parasitology Research, Jun 30, 2021
Naegleria fowleri, a free-living and thermophilic ameba, is the etiological agent of primary ameb... more Naegleria fowleri, a free-living and thermophilic ameba, is the etiological agent of primary amebic meningoencephalitis (PAM). PAM is a rare and highly fatal neurologic disease in humans, and has been rarely documented in animal species. This report describes the pathological and etiological findings of a fatal case of N. fowleri-associated meningoencephalitis in a cow in Southern Brazil. Microscopic findings were consistent with severe, multifocal, hemorrhagic, and necrosuppurative meningoencephalitis associated with a large number of amebic trophozoites compatible with N. fowleri. Brain samples subjected to molecular assays generated a 315 bp fragment, which presented 99% identity with a N. fowleri sequence previously deposited in GenBank. This is the first study reporting the molecular detection of N. fowleri in a case of cattle meningoencephalitis in Latin America, and the obtained sequence represents the first GenBank deposit of N. fowleri identified in Brazil to this day. Additionally, the case reported is the second occurrence of N. fowleri-associated disease in the same city, drawing attention to the local importance of infection by this ameba and potential risk for human infections.
Brazilian Journal of Microbiology, May 22, 2021
Porcine encephalomyelitis can be associated with many etiologies, including viral agents, such as... more Porcine encephalomyelitis can be associated with many etiologies, including viral agents, such as Porcine teschovirus (PTV), Porcine sapelovirus (PSV), and Porcine astrovirus (PoAstV). In this study, we investigated the presence of these viruses in a neurological disease outbreak in a swine farm in Southern Brazil. The piglet production farm unity had 1200 weaning piglets, and 40 piglets with neurological signs such as motor incoordination, paresis, and paralysis of hind limbs, with an evolution time of approximately 4 days. Among these, 10 piglets were submitted to postmortem examination. Gross lesions were restricted to a mild enlargement of the nerve roots and ganglia of spinal cord segments. The microscopic lesions were characterized by nonsuppurative encephalomyelitis and ganglioneuritis with evident neuronal degeneration and necrosis. Samples of the central nervous system (CNS), cerebrospinal fluid, and feces were collected and submitted to molecular analysis. PTV was identified in all samples of the CNS, while eight of the piglets were also positive for PSV, and seven were positive for Porcine enterovirus (EV-G). PoAstV was identified in a pool of feces of healthy animals used as controls. This study demonstrates the occurrence of encephalomyelitis associated with PTV on a swine farm in Southern Brazil, as well as the presence of other viruses such as PSV, EV-G, and PoAstV in the swineherd. Sequences of the fragments that were previously amplified by PCR showed a high similarity to PTV 6. Herein, we describe the first case report of severe swine polioencephalomyelitis associated with PTV in South America.
Ciencia Rural, 2021
Salmonellosis is a bacterial disease that affects several domestic animal species, and is commonl... more Salmonellosis is a bacterial disease that affects several domestic animal species, and is commonly diagnosed in cattle, horses, and pigs. This study aimed to describe the epidemiological and pathological findings of eleven cases of enteric salmonellosis and two cases of salmonellosis with pulmonary involvement in cattle in Rio Grande do Sul State, Brazil. Clinical signs included fever, yellow diarrhea, sometimes with blood streaks, and dyspnea, with a clinical course ranging from 1 to 30 days. Eight cases occurred as outbreaks, whereas five cases occurred individually. Risk factors included inadequate handling practices, such as overcrowded facilities and comorbidities, including anaplasmosis. The main gross finding of the enteric presentation was fibrinonecrotic enterocolitis, occasionally associated with button ulcers, mesenteric lymphadenomegaly, splenomegaly, cholecystitis and hepatomegaly. In addition, one steer with a chronic clinical progression presented severe segmental thickening of the ileum, associated with intestinal rupture and peritonitis. In the respiratory system, the main findings were reddened, non-collapsed lungs, with multifocal areas of atelectasis. The main microscopic findings were observed in the small and large intestines, and these were characterized by severe necrosis and mucosal ulceration, associated with marked inflammatory infiltrate of neutrophils and fibrin deposition intermixed by rod-shaped bacterial aggregates, and fibrosis, as well as interstitial pneumonia. Seven cases yielded positive bacterial cultures for Salmonella spp. and three serovars, namely Typhimurium, Dublin, and Panama were identified. All cases exhibited immunolabeling for Salmonella spp. using immunohistochemistry.
Brazilian Journal of Microbiology, Apr 27, 2022
Visna-maedi is a multisystemic and progressive inflammatory disease caused by a non-oncogenic ret... more Visna-maedi is a multisystemic and progressive inflammatory disease caused by a non-oncogenic retrovirus (Visna-maedi virus, VMV). An outbreak of visna-maedi occurred in Southern Brazil in sheep with clinical signs of blindness and stumbling gait. At post-mortem examination, all animals had similar lesions, including heavy non-collapsed lungs and multifocal yellow areas in the cerebral white matter, affecting mainly the periventricular region. These lesions corresponded histologically to lymphocytic interstitial pneumonia and histiocytic periventricular encephalitis surrounding areas of necrosis, in addition to significant demyelination in the brain. Serology was performed in all the sheep from the flock and 14% were seropositive for VMV. The presence of VMV was confirmed through PCR and partial sequencing of the 5′LTR. Sequencing demonstrated that the virus had 89.7 to 90.0% of nucleotide identity with VMV strains reported in the USA. This is the first description of clinical disease related to VMV in Brazil leading to economic losses. This study calls for the need to implement control measures to prevent the spread of small ruminant lentiviruses in Brazil.
Revista Brasileira De Medicina Veterinaria, Sep 15, 2016
Occurrence of anti-Neospora caninum antibodies in dairy cattle in the western of Santa Catarina, ... more Occurrence of anti-Neospora caninum antibodies in dairy cattle in the western of Santa Catarina, Brazil.] Ocorrência de anticorpos anti-Neospora caninum em bovinos leiteiros no oeste do estado de Santa Catarina, Brasil.
Acta Scientiae Veterinariae, Jun 27, 2017
Background: Infectious diseases have expanded their host and geographic ranges, increasing impact... more Background: Infectious diseases have expanded their host and geographic ranges, increasing impacts on both human and animal health. Mycoplasma gallisepticum usually causes avian chronic respiratory conditions and Histomonas meleagridis infects the cecum and the liver of poultry. Although these diseases have been reported in several bird species, information associated with their prevalence and impact in local flocks of ornamental birds is scarce. This communication describes severe outbreaks of mycoplasmosis and histomoniasis that affected a southern Brazilian commercial flock of ornamental birds. Case: The outbreaks occurred in an ornamental bird flock that contained 2,340 birds from 39 different species, distributed mostly in the orders Galliformes, Anseriformes, and Psittaciformes. Mycoplasma gallisepticum affected 12 chukar partridges, 12 Indian peacocks, 19 ornamental chickens and 46 individuals of 4 species of pheasant. The disease cases were distributed between April and July 2015. A total of 36 birds died due to the disease' complications and most surviving birds suffered from severe ocular sequels, which determined their subsequent culling, despite attempts of different treatment protocols. The main signs included coughing, sneezing, infraorbital swelling, wasting, and death which were mostly associated with caseous sinusitis. Affected birds had positive samples when stained with anti-Mycoplasma gallisepticum immunohistochemistry and tested by Mycoplasma gallisepticum-Polymerase Chain Reaction. The application of 2 doses of a Mycoplasma gallisepticum vaccine in early 2016 to all the Galliformes in the flock reduced the annual prevalence to 4 clinical cases. Histomoniasis affected and killed 19 out of 27 chukar partridges that were being kept with ring-necked pheasants in the same enclosure. The disease occurred between September and December 2016 and a high prevalence of Heterakis gallinarum was detected in the flock. The main findings included apathy and death linked to hepatic and cecal necrosis. Admixed in the necrotic areas, there were numerous round to oval, eosinophilic, protozoal trophozoites of 15-20 µm in diameter, occasionally containing a 3-5 µm centrally located basophilic nucleus (histomonads) surrounded by a clear halo. Anthelmintic dosing, exchanging and liming the bedding material of the enclosures, and keeping the remaining partridges in an aerial aviary with a wire mesh floor prevented additional cases of histomoniasis. Discussion: In Brazil, as in other countries, the sanitary management practices applied in commercial chicken production reached high levels of technification. However, this is not the case in ornamental bird breeding systems, which may still suffer the impacts of diseases that are practically extinct in industrial chicken flocks. For both diseases, diagnosis was based on typical clinical signs and detection of the pathogens in association with characteristic pathological findings. The occurrence of mycoplasmosis and histomoniasis was associated with improper management practices at the farm; the main risk factors observed were a high turnover of birds, the absence of quarantine, the absence of basic health care, overcrowding and poor hygiene. The prevention of further cases of both diseases was mostly established with the application of basic sanitary measures, including vaccination and anthelmintic dosing, for mycoplasmosis and histomoniasis respectively. This report alerts bird keepers and avian veterinarians of the importance of establishing proper sanitary management in local ornamental bird flocks. Because some of the ornamental bird species that have been commercially propagated worldwide may be included in the list of threatened species, the findings described here also show that simple health care may promote the fight against extinctions.
Tropical Animal Health and Production, Apr 17, 2019
Enzootic nasal tumor (ENT) is a contagious neoplasm associated with enzootic nasal tumor virus (E... more Enzootic nasal tumor (ENT) is a contagious neoplasm associated with enzootic nasal tumor virus (ENTV), which may induce disease in sheep (ENTV-1) and goats (ENTV-2). This study aimed to describe the occurrence of ENT in two Texel sheep (Ovis aries) from a 75-sheep flock, located in the city of Gravataí, southern Brazil. Animals used to be purchased from different origins, and no specific tests for disease monitoring or quarantine procedure were performed. Affected animals presented respiratory distress, anorexia with severe weight loss, and mucopurulent unilateral nasal discharge. Necropsy was performed in both animals and nasal cavity masses were observed. Histopathological analysis demonstrated an epithelial neoplasm compatible with nasal adenocarcinoma. PCR using a protocol that amplifies a 591 bp sequence of 5'LTR-gag region of ENTV1 was performed followed by DNA sequencing. Both samples were positive, and the sequences obtained presented highest identity (97%) with ENTV strain TN28 (GenBank accession number MH899613) detected in a Texel sheep from Scotland. This is the first report of ENTV-1 leading to enzootic nasal tumor in sheep in Latin America, which confirms the presence of the retrovirus in sheep flocks in the Brazilian territory.
Revista Brasileira De Parasitologia Veterinaria, 2022
This is an Open Access article distributed under the terms of the Creative Commons Attribution Li... more This is an Open Access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Outbreak of toxoplasmosis associated with muscular lesions in finishing pigs caused by an atypical Toxoplasma gondii genotype Surto de toxoplasmose associado a lesões musculares em suínos de terminação causado por um genótipo atípico de T. gondii
Pesquisa Veterinaria Brasileira, 2022
RESUMO.-[Osteoporose em suínos.] Quarenta e seis suínos apresentaram fraqueza muscular, paresia e... more RESUMO.-[Osteoporose em suínos.] Quarenta e seis suínos apresentaram fraqueza muscular, paresia e paralisia de membros pélvicos, perda de peso, decúbito lateral e morte, com um curso clínico de 7 a 10 dias. Dois suínos foram submetidos a necropsia e exibiram fragilidade óssea, formação de calo ósseo, e múltiplas fraturas em membros, costelas e vértebras. Microscopicamente notou-se difusamente um marcado decréscimo na espessura e número de trabéculas ósseas. Essas estavam desconexas, com uma aparência de flutuação, enquanto o córtex dos ossos longos estava afinado, com um aumento da porosidade pela dilatação dos canais de Haversian, erosão endosteal e diminuição da atividade osteoblástica. Espectrofotometria por chama foi realizada em amostras de fígado, e revelou um excesso de zinco (>2300ppm) e deficiência de cobre (<33.1ppm). Neste trabalho, apresentamos a primeira descrição patológica de um surto de osteoporose em suínos, além de fornecer uma breve revisão de doenças metabólicas em suínos.
Pesquisa Veterinaria Brasileira, 2021
RESUMO.-[Causas de morte em ovinos no Sul do Brasil: análise de 523 casos (2004-2019).] O aumento... more RESUMO.-[Causas de morte em ovinos no Sul do Brasil: análise de 523 casos (2004-2019).] O aumento da comercialização de produtos ovinos requer um aumento equivalente na sanidade do rebanho e uma rápida identificação de doenças. Os dados sobre as causas de morte em ovinos foram revisados no banco de dados do Setor de Patologia Veterinária da Universidade Federal do Rio Grande do Sul, entre janeiro de 2004 e dezembro de 2019. Aspectos epidemiológicos, como raça, sexo e idade, além das características clínicas e patológicas, foram compilados. Nesse período, foram avaliados tecidos de 523 ovinos, em que o diagnóstico conclusivo foi obtido em 457 (87%) dos casos. A grande maioria dos ovinos era da mesorregião metropolitana de Porto Alegre. A raça mais comum foi Texel 171/523 (33%). De todos os diagnósticos conclusivos, 158/457 (35%) corresponderam a doenças infecciosas não-parasitárias, 117/457 (26%) foram causadas por doenças tóxicas, 95/457 (21%) doenças infecciosas parasitárias, 42/457 (9%) foram incluídos na categoria nutricional e metabólica, 38/457 (8%) foram classificadas na categoria "outros", e 7/457 (1,5%) eram defeitos congênitos. A faixa etária das ovelhas incluídas neste estudo foi de um dia a sete anos de idade. Entre os casos com diagnóstico conclusivo, a principal causa de óbito foi hemoncose com 83/457 (18%) dos casos, seguida de pneumonia 29/457 (6%), intoxicação por Baccharis sp. 25/457 (5%), e infecção pelo vírus da língua azul 22/457 (5%).
Journal of Comparative Pathology
Brazilian Journal of Microbiology
Ciencia Rural, 2021
Cardiac malformations are reported to be relatively rare in bovine species, with ventricular sept... more Cardiac malformations are reported to be relatively rare in bovine species, with ventricular septal defects being the most common abnormality observed predominantly in young calves. This report aims to describe the cardiac malformations observed in bovids and review the literature related to those malformations in this species. The necropsy reports of 1,783 bovids were reviewed, and 0.4% were diagnosed with a cardiac congenital defect. The most common cardiac congenital malformation detected in this study was ventricular septal defect, observed alone or associated with other anomalies (in one case, as part of tetralogy of Fallot); followed by atrial septal defect, also alone or with other cardiac malformations. Secondary findings in the lungs and liver were observed in 75% of all cases. Histologic cardiac lesions were identified in 25% of all cases, characterized mainly by fibrosis. Other congenital malformations in different organs were observed in 25% of the cases. Considering the importance of cardiac congenital malformations observed in this study, these conditions should be considered as a differential diagnosis for calves who died with no specific clinical signs. Furthermore, macroscopic evaluation is crucial for the diagnosis of cardiac congenital malformations.
Ciência Rural, 2021
ABSTRACT: Salmonellosis is a bacterial disease that affects several domestic animal species, and ... more ABSTRACT: Salmonellosis is a bacterial disease that affects several domestic animal species, and is commonly diagnosed in cattle, horses, and pigs. This study aimed to describe the epidemiological and pathological findings of eleven cases of enteric salmonellosis and two cases of salmonellosis with pulmonary involvement in cattle in Rio Grande do Sul State, Brazil. Clinical signs included fever, yellow diarrhea, sometimes with blood streaks, and dyspnea, with a clinical course ranging from 1 to 30 days. Eight cases occurred as outbreaks, whereas five cases occurred individually. Risk factors included inadequate handling practices, such as overcrowded facilities and comorbidities, including anaplasmosis. The main gross finding of the enteric presentation was fibrinonecrotic enterocolitis, occasionally associated with button ulcers, mesenteric lymphadenomegaly, splenomegaly, cholecystitis and hepatomegaly. In addition, one steer with a chronic clinical progression presented severe seg...
Ciência Rural, 2018
ABSTRACT: In this work, we describe an unusual case of fibrinous pleuropneumonia caused by Pasteu... more ABSTRACT: In this work, we describe an unusual case of fibrinous pleuropneumonia caused by Pasteurella multocida associated with generalized lymphadenomegaly in a bovine. The animal had a one-month history of generalized superficial lymphadenomegaly that progressed to anorexia and submandibular oedema, resulting in spontaneous death. At necropsy, the parenchyma of the lymph nodes and multiple organs was obliterated by a dense proliferation of round neoplastic cells (lymphoma). Additionally, the neoplasm presented multifocal areas of haemorrhage and necrosis, characteristic of lymphoma. The parietal and visceral pleura and parietal pericardium were enlarged and covered diffusely with large amounts of a yellowish fibrillary material. The lungs were mildly enlarged, non-collapsed, and firm and exhibited interlobular septae that were thickened with a gelatinous material. Histopathological examination showed that the parietal and visceral pleura were enlarged due to a diffuse and severe ...
Ciência Rural, 2021
ABSTRACT: Cardiac malformations are reported to be relatively rare in bovine species, with ventri... more ABSTRACT: Cardiac malformations are reported to be relatively rare in bovine species, with ventricular septal defects being the most common abnormality observed predominantly in young calves. This report aims to describe the cardiac malformations observed in bovids and review the literature related to those malformations in this species. The necropsy reports of 1,783 bovids were reviewed, and 0.4% were diagnosed with a cardiac congenital defect. The most common cardiac congenital malformation detected in this study was ventricular septal defect, observed alone or associated with other anomalies (in one case, as part of tetralogy of Fallot); followed by atrial septal defect, also alone or with other cardiac malformations. Secondary findings in the lungs and liver were observed in 75% of all cases. Histologic cardiac lesions were identified in 25% of all cases, characterized mainly by fibrosis. Other congenital malformations in different organs were observed in 25% of the cases. Consi...