ABSTRACT
Background: Feline calicivirus (FCV) and felid herpesvirus type 1 (FeHV-1) are widely distributed in the feline population. These viruses are the main cause of upper respiratory tract disease in this species, and FCV can also causes oral disease characterized by stomatitis and ulcers. Furthermore, FCV has been associated with a systemic hemorrhagic syndrome named FCV-associated virulent systemic disease (FCV-VSD), which has not yet been reported in Brazil. The aim of the present study was to investigate the presence of antibodies against FCV and FeHV-1 in the population of domestic felines from some counties of the Rio Grande do Sul State (RS), using a virus neutralizing (VN) assay. Materials, Methods & Results: A total of 630 feline serum samples collected between the years 2007 and 2011 were analyzed to detect antibodies against FCV and FeHV-1 by a VN assay. The serum samples came from cats admitted in veterinary clinics, household cats and cats examined in veterinary hospitals at three universities from Rio Grande do Sul State (RS) [UFRGS, UFSM and UPF]. The serum samples were classified according to the origin, gender, age and vaccination status of the cat. All animal handling procedures were performed under veterinary supervision and following the recommendations of the Brazilian Committee on Animal Experimentation. The feline cell line CRFK (Crandell-Rees feline kidne
Background: Feline calicivirus (FCV) and felid herpesvirus type 1 (FeHV-1) are widely distributed in the feline population. These viruses are the main cause of upper respiratory tract disease in this species, and FCV can also causes oral disease characterized by stomatitis and ulcers. Furthermore, FCV has been associated with a systemic hemorrhagic syndrome named FCV-associated virulent systemic disease (FCV-VSD), which has not yet been reported in Brazil. The aim of the present study was to investigate the presence of antibodies against FCV and FeHV-1 in the population of domestic felines from some counties of the Rio Grande do Sul State (RS), using a virus neutralizing (VN) assay. Materials, Methods & Results: A total of 630 feline serum samples collected between the years 2007 and 2011 were analyzed to detect antibodies against FCV and FeHV-1 by a VN assay. The serum samples came from cats admitted in veterinary clinics, household cats and cats examined in veterinary hospitals at three universities from Rio Grande do Sul State (RS) [UFRGS, UFSM and UPF]. The serum samples were classified according to the origin, gender, age and vaccination status of the cat. All animal handling procedures were performed under veterinary supervision and following the recommendations of the Brazilian Committee on Animal Experimentation. The feline cell line CRFK (Crandell-Rees feline kidne
ABSTRACT
Background: Feline calicivirus (FCV) and felid herpesvirus type 1 (FeHV-1) are widely distributed in the feline population. These viruses are the main cause of upper respiratory tract disease in this species, and FCV can also causes oral disease characterized by stomatitis and ulcers. Furthermore, FCV has been associated with a systemic hemorrhagic syndrome named FCV-associated virulent systemic disease (FCV-VSD), which has not yet been reported in Brazil. The aim of the present study was to investigate the presence of antibodies against FCV and FeHV-1 in the population of domestic felines from some counties of the Rio Grande do Sul State (RS), using a virus neutralizing (VN) assay. Materials, Methods & Results: A total of 630 feline serum samples collected between the years 2007 and 2011 were analyzed to detect antibodies against FCV and FeHV-1 by a VN assay. The serum samples came from cats admitted in veterinary clinics, household cats and cats examined in veterinary hospitals at three universities from Rio Grande do Sul State (RS) [UFRGS, UFSM and UPF]. The serum samples were classified according to the origin, gender, age and vaccination status of the cat. All animal handling procedures were performed under veterinary supervision and following the recommendations of the Brazilian Committee on Animal Experimentation. The feline cell line CRFK (Crandell-Rees feline kidne
Background: Feline calicivirus (FCV) and felid herpesvirus type 1 (FeHV-1) are widely distributed in the feline population. These viruses are the main cause of upper respiratory tract disease in this species, and FCV can also causes oral disease characterized by stomatitis and ulcers. Furthermore, FCV has been associated with a systemic hemorrhagic syndrome named FCV-associated virulent systemic disease (FCV-VSD), which has not yet been reported in Brazil. The aim of the present study was to investigate the presence of antibodies against FCV and FeHV-1 in the population of domestic felines from some counties of the Rio Grande do Sul State (RS), using a virus neutralizing (VN) assay. Materials, Methods & Results: A total of 630 feline serum samples collected between the years 2007 and 2011 were analyzed to detect antibodies against FCV and FeHV-1 by a VN assay. The serum samples came from cats admitted in veterinary clinics, household cats and cats examined in veterinary hospitals at three universities from Rio Grande do Sul State (RS) [UFRGS, UFSM and UPF]. The serum samples were classified according to the origin, gender, age and vaccination status of the cat. All animal handling procedures were performed under veterinary supervision and following the recommendations of the Brazilian Committee on Animal Experimentation. The feline cell line CRFK (Crandell-Rees feline kidne
ABSTRACT
Feline calicivirus (FCV) and feline herpesvirus type 1 (FHV-1) are the two primary causes of upper respiratory tract disease in cats. The aim of this study was to demonstrate the distribution of FCV and FHV-1 among the feline population of several counties in Rio Grande do Sul State, Brazil. To this end, conjunctival and nasal swabs were collected from 302 cats from different locations, including households, breeding catteries, veterinary clinics, animal hospitals and experimental research facilities. The samples were collected between July 2006 to June 2009. The virus isolation was performed in CRFK cells and, subsequently, the identification was confirmed by PCR. FCV, FHV-1, or both were isolated from 55 cats from 28 different locations. FCV alone was isolated from 52.7% (29/55) of the animals that tested positively, FHV-1 alone was isolated from 38.2% (21/55) of the animals that tested positively, and co-infection were detected in 9.1% (5/55) of the animals that tested positively. Virus detection was more prevalent in cats that were less than 1 year old, among animals that shared a living space with other cats, and females. FCV and FHV-1 were isolated from vaccinated cats. In addition, both viruses were isolated from cats that showed no signs of disease. The results suggest that a carrier state is common for both viruses in the evaluated population. A search for other causes of respiratory disease in that population is necessary; and further studies relating to the molecular characterization of viruses and vaccine efficacy are also necessary.
ABSTRACT
West Nile virus (WNV) envelope glycoproteins preM/E were stably expressed in baby hamster kidney cells and tested as antigen in a fluorescent antibody assay for WNV antibodies. Sera from horses, mice and chicken immunized with an inactivated WNV vaccine and, less consistently, sera from horses acutely infected with WNV, reacted specifically with viral antigens present in preM/E-expressing cells.
ABSTRACT
Bovine herpesvirus type 5 (BoHV-5) is the agent of meningoencephalitis, an important disease of cattle in South America. The neuropathogenesis of BoHV-5 infection is poorly understood and most previous research focused on the role of envelope glicoproteins in neurovirulence. Thymidine kinase (TK) is a viral enzyme necessary for virus replication in neurons and, therefore, represents a potential target for virus attenuation. The selection and characterization of BoHV-5 variants resistant to the nucleoside analog brivudin (BVDU), which selects TK-defective viruses is here described. Several BVDU-resistant clones were obtained after multiple passages in tissue culture in the presence of BVDU and one clone (BoHV-5/R-27) was further characterized. The selected clone replicated to similar titers and produced plaques with similar size and morphology to those of wild-type virus (SV507/99). The genetic stability of the resistant virus was demonstrated after ten passages in cell culture in the absence of the drug. Moreover, the drug-resistant virus showed reduced virulence in a rabbit model: virus inoculation in four rabbits did not result in disease, in contrast with 75% morbidity (3/4) and 50% mortality (2/2) among rabbits inoculated with the parental virus. These results demonstrate that BoHV-5 is sensitive to BVDU and that drug-resistant mutants can be readily selected upon BVDU treatment. BVDU-resistant mutants, likely defective in TK, retained their ability to replicate in tissue culture yet were attenuated for rabbits. This strategy to obtain TK-defective BoHV-5 may be useful to study the role of TK in BoHV-5 neuropathogenesis and for vaccine development.
ABSTRACT
A 3-year-old, mixed breed, male horse showed multiple nodules in different areas of the skin. Lesions occurred predominantly on the lips, cheeks, and submandibular and right inguinal regions. The nodules were characterized as mixed, fibroblastic, verrucous and occult types of sarcoid. Histologically there was proliferation of dermal fibroblasts, with or without pseudoepitheliomatous hyperplasia of the epidermis (frequently ulcerated), and formation of small isolated groups of neoplastic fibroblasts in the superficial dermis. Three tissue samples were submitted to DNA extraction and PCR amplification with generic primers for the internal region of the papillomavirus L1 gene. The amplified products from two samples were sequenced and showed 99% identity with the bovine papillomavirus (BPV) BR-UEL-4. This is the first description of BPV BR-UEL-4 infecting a horse and causing sarcoid in this species. BPV BR-UEL-4 is a putative new BPV type recently identified in skin papillomas in a Brazilian cattle herd.
Um equino, sem raça definida, macho com três anos de idade apresentou múltiplos nódulos na pele, em diversas regiões do corpo. As lesões localizavam-se predominantemente nos lábios, nas bochechas, na região submandibular e na região inguinal direita. Os tumores caracterizavam-se como sarcoides dos tipos misto, fibroblástico, verrucoso e oculto. Histologicamente apresentaram proliferação de fibroblastos dérmicos, muitas vezes ulcerado, com ou sem hiperplasia pseudoepiteliomatosa da epiderme e formação de pequenos grupos isolados de fibroblastos neoplásicos na derme superficial. Três amostras de tecido foram submetidas à extração de DNA e amplificação por PCR com oligonucleotídeos iniciadores genéricos direcionados para uma região interna do gene L1 dos papilomavírus. Os produtos resultantes da amplificação de duas amostras foram sequenciados e demonstraram identidade de 99% com o papilomavírus bovino (BPV) BR-UEL-4. Essa é a primeira descrição da infecção de equinos, bem como de sua associação com sarcoide pelo BPV BR-UEL-4, um suposto novo tipo de BPV identificado recentemente no Brasil a partir de papilomas cutâneos em bovinos.
ABSTRACT
A 3-year-old, mixed breed, male horse showed multiple nodules in different areas of the skin. Lesions occurred predominantly on the lips, cheeks, and submandibular and right inguinal regions. The nodules were characterized as mixed, fibroblastic, verrucous and occult types of sarcoid. Histologically there was proliferation of dermal fibroblasts, with or without pseudoepitheliomatous hyperplasia of the epidermis (frequently ulcerated), and formation of small isolated groups of neoplastic fibroblasts in the superficial dermis. Three tissue samples were submitted to DNA extraction and PCR amplification with generic primers for the internal region of the papillomavirus L1 gene. The amplified products from two samples were sequenced and showed 99% identity with the bovine papillomavirus (BPV) BR-UEL-4. This is the first description of BPV BR-UEL-4 infecting a horse and causing sarcoid in this species. BPV BR-UEL-4 is a putative new BPV type recently identified in skin papillomas in a Brazilian cattle herd.
Um equino, sem raça definida, macho com três anos de idade apresentou múltiplos nódulos na pele, em diversas regiões do corpo. As lesões localizavam-se predominantemente nos lábios, nas bochechas, na região submandibular e na região inguinal direita. Os tumores caracterizavam-se como sarcoides dos tipos misto, fibroblástico, verrucoso e oculto. Histologicamente apresentaram proliferação de fibroblastos dérmicos, muitas vezes ulcerado, com ou sem hiperplasia pseudoepiteliomatosa da epiderme e formação de pequenos grupos isolados de fibroblastos neoplásicos na derme superficial. Três amostras de tecido foram submetidas à extração de DNA e amplificação por PCR com oligonucleotídeos iniciadores genéricos direcionados para uma região interna do gene L1 dos papilomavírus. Os produtos resultantes da amplificação de duas amostras foram sequenciados e demonstraram identidade de 99% com o papilomavírus bovino (BPV) BR-UEL-4. Essa é a primeira descrição da infecção de equinos, bem como de sua associação com sarcoide pelo BPV BR-UEL-4, um suposto novo tipo de BPV identificado recentemente no Brasil a partir de papilomas cutâneos em bovinos.
ABSTRACT
Two Brazilian isolates of bovine viral diarrhea virus type 2 (BVDV-2) were inoculated in calves to evaluate their virulence and to study the pathogenesis of the infection. Previously to virus inoculation, the calves were immunossupressed with dexamethasone. Four 45 to 90-days-old calves (group A) were inoculated with isolate SV-260 (n=2) or LV-96 (n=2), and four 6 to 8-months-old calves (group B) were inoculated with isolate SV-260. Following virus inoculation, group A calves showed anorexia, depression, hyperthermia, signs of respiratory infection and profuse diarrhea, bloody in two cases. The respiratory and digestive signs progressed and the animals died or were euthanized in extremis between days 7 and 12 post-inoculation. Ulcers and erosions in the digestive tract (tongue, n=4; esophagus, n=1; rumen, n=1 and abomasum, n=3), edema of the lung (n=4) and abomasal mucosa (n=3); echimosis and suffusions in the spleen serosa (n=2), rumen, small intestine and ceccum (n=1), heart (n=1) and urinary bladder mucosa (n=1) and intestinal intussuseption (n=1) were the most prominent findings. Ulcerations and erosions accompanied by mononuclear cell infiltrates in the digestive tract mucosa and submucosa, and lymphoid depletion in lymph nodes and Peyers patches were frequently observed. Infectious virus was detected in several tissues and organs. Viral antigens were detected by immunohistochemistry mainly in epithelial cells of the digestive tract, in mononuclear cells of the perivascular and peribronchial spaces; in lymph node septae and capsule; and in lymphocytes and other mononuclear cells of the spleen and Peyers patches. Group B calves showed depression, hyperthermia, moderate signs of respiratory and digestive infection, small ulcerations in the tongue and recovered after a few days. These results demonstrate that the Brazilian BVDV-2 isolates were capable of producing an acute disease in calves upon experimental inoculation, and that the clinical and pathological consequences of the infection were more severe in young calves.
Duas amostras brasileiras do vírus da Diarréia Viral Bovina tipo 2 (BVDV-2) foram inoculadas em bezerros com o objetivo de avaliar a sua virulência e estudar a patogenia da infecção. Previamente à inoculação, os animais foram imunodeprimidos com dexametasona. Quatro bezerros com idades entre 45 e 90 dias (grupo A) foram inoculados com a amostra SV-260 (n=2) ou LV-96 (n=2) e quatro bezerros com 6 a 8 meses de idade foram inoculados com a amostra SV-260 (grupo B). Após a inoculação, os bezerros do grupo A apresentaram anorexia, depressão, hipertermia, sinais de infecção respiratória e diarréia profusa, acompanhada de melena em dois animais. Os sinais respiratórios e digestivos progrediram, e os animais morreram ou foram sacrificados in extremis entre os dias 7 e 12 pós-inoculação. Úlceras e erosões no trato digestivo (língua, n=4; esôfago, n=1; rúmen, n=1 e abomaso, n=3), edema pulmonar (n=4) e na mucosa do abomaso (n=3); equimoses e sufusões na serosa do baço (n=2), no rúmen, no intestino delgado e no ceco (n=1), no coração (n=1) e na mucosa da bexiga (n=1) e intussuscepção intestinal (n=1) foram os achados macroscópicos mais marcantes. Úlceras e erosões, acompanhadas de infiltrado mononuclear na mucosa e submucosa do trato digestivo e depleção linfóide nos linfonodos e placas de Peyer, foram as alterações microscópicas mais freqüentes. O vírus foi detectado em vários tecidos e órgãos. Antígenos virais foram demonstrados por imuno-histoquímica, principalmente em células epiteliais do trato digestivo; em células mononucleares nos espaços perivasculares e peribronquiais; na cápsula e septos de linfonodos; e em linfócitos e células mononucleares das placas de Peyer e baço. Os animais do grupo B apresentaram depressão, hipertermia, sinais moderados de infecção respiratória e digestiva, ulcerações na língua e bochecha, mas recuperaram-se após alguns dias. Esses resultados demonstram que as amostras de BVDV-2 foram capazes de reproduzir a enfermidade aguda quando inoculadas em bezerros e que as conseqüências clínico-patológicas da infecção foram mais severas nos animais mais jovens.
ABSTRACT
Two Brazilian isolates of bovine viral diarrhea virus type 2 (BVDV-2) were inoculated in calves to evaluate their virulence and to study the pathogenesis of the infection. Previously to virus inoculation, the calves were immunossupressed with dexamethasone. Four 45 to 90-days-old calves (group A) were inoculated with isolate SV-260 (n=2) or LV-96 (n=2), and four 6 to 8-months-old calves (group B) were inoculated with isolate SV-260. Following virus inoculation, group A calves showed anorexia, depression, hyperthermia, signs of respiratory infection and profuse diarrhea, bloody in two cases. The respiratory and digestive signs progressed and the animals died or were euthanized in extremis between days 7 and 12 post-inoculation. Ulcers and erosions in the digestive tract (tongue, n=4; esophagus, n=1; rumen, n=1 and abomasum, n=3), edema of the lung (n=4) and abomasal mucosa (n=3); echimosis and suffusions in the spleen serosa (n=2), rumen, small intestine and ceccum (n=1), heart (n=1) and urinary bladder mucosa (n=1) and intestinal intussuseption (n=1) were the most prominent findings. Ulcerations and erosions accompanied by mononuclear cell infiltrates in the digestive tract mucosa and submucosa, and lymphoid depletion in lymph nodes and Peyers patches were frequently observed. Infectious virus was detected in several tissues and organs. Viral antigens were detected by immunohistochemistry mainly in epithelial cells of the digestive tract, in mononuclear cells of the perivascular and peribronchial spaces; in lymph node septae and capsule; and in lymphocytes and other mononuclear cells of the spleen and Peyers patches. Group B calves showed depression, hyperthermia, moderate signs of respiratory and digestive infection, small ulcerations in the tongue and recovered after a few days. These results demonstrate that the Brazilian BVDV-2 isolates were capable of producing an acute disease in calves upon experimental inoculation, and that the clinical and pathological consequences of the infection were more severe in young calves.
Duas amostras brasileiras do vírus da Diarréia Viral Bovina tipo 2 (BVDV-2) foram inoculadas em bezerros com o objetivo de avaliar a sua virulência e estudar a patogenia da infecção. Previamente à inoculação, os animais foram imunodeprimidos com dexametasona. Quatro bezerros com idades entre 45 e 90 dias (grupo A) foram inoculados com a amostra SV-260 (n=2) ou LV-96 (n=2) e quatro bezerros com 6 a 8 meses de idade foram inoculados com a amostra SV-260 (grupo B). Após a inoculação, os bezerros do grupo A apresentaram anorexia, depressão, hipertermia, sinais de infecção respiratória e diarréia profusa, acompanhada de melena em dois animais. Os sinais respiratórios e digestivos progrediram, e os animais morreram ou foram sacrificados in extremis entre os dias 7 e 12 pós-inoculação. Úlceras e erosões no trato digestivo (língua, n=4; esôfago, n=1; rúmen, n=1 e abomaso, n=3), edema pulmonar (n=4) e na mucosa do abomaso (n=3); equimoses e sufusões na serosa do baço (n=2), no rúmen, no intestino delgado e no ceco (n=1), no coração (n=1) e na mucosa da bexiga (n=1) e intussuscepção intestinal (n=1) foram os achados macroscópicos mais marcantes. Úlceras e erosões, acompanhadas de infiltrado mononuclear na mucosa e submucosa do trato digestivo e depleção linfóide nos linfonodos e placas de Peyer, foram as alterações microscópicas mais freqüentes. O vírus foi detectado em vários tecidos e órgãos. Antígenos virais foram demonstrados por imuno-histoquímica, principalmente em células epiteliais do trato digestivo; em células mononucleares nos espaços perivasculares e peribronquiais; na cápsula e septos de linfonodos; e em linfócitos e células mononucleares das placas de Peyer e baço. Os animais do grupo B apresentaram depressão, hipertermia, sinais moderados de infecção respiratória e digestiva, ulcerações na língua e bochecha, mas recuperaram-se após alguns dias. Esses resultados demonstram que as amostras de BVDV-2 foram capazes de reproduzir a enfermidade aguda quando inoculadas em bezerros e que as conseqüências clínico-patológicas da infecção foram mais severas nos animais mais jovens.