Detection of respiratory viruses in shelter dogs maintained under varying environmental conditions

Abstract Three dog shelters in Rio Grande do Sul were investigated for associations between the occurrence of respiratory viruses and shelter environmental conditions. Nasal secretions randomly collected during the cold season were tested via PCR, and this data collection was followed by nucleotide sequencing of the amplicons. In shelter #1 (poor sanitary and nutritional conditions, high animal density and constant contact between dogs), 78% (58/74) of the nasal samples were positive, 35% (26/74) of which were in single infections and 44% (32/74) of which were in coinfections. Shelters #2 and #3 had satisfactory sanitary and nutritional conditions, outdoors exercise areas (#2) and animal clustering by groups (#3). In shelter #2, 9% (3/35) of the samples were positive for Canine parainfluenza virus (CPIV), and 6% (2/35) were positive for Canid herpesvirus 1 (CaHV-1). In shelter #3, 9% (7/77) of the samples were positive for Canine adenovirus type 2 (CAdV-2), and 1% (1/77) were positive for Canine distemper virus (CDV). The amplicon sequences (CPIV and CDV nucleoprotein gene; CAdV-2 E3 gene; CaHV-1 glycoprotein B gene) showed 94-100% nucleotide identity with GenBank sequences. Our results demonstrate that CPIV, CAdV-2 and CDV are common in dog shelters and that their frequencies appear to be related with environmental and nutritional conditions. These results indicate the need for control/prevention measures, including vaccination and environmental management, to minimize these infections and improve dog health.

Equine influenza in Brazil / A influenza equina no Brasil

Equine influenza virus (EIV) (H3N8 and H7N7) is the causative agent of equine influenza, or equine flu. The H7N7 subtype has been considered to be extinct worldwide since 1980. Affected animals have respiratory symptoms that can be worsened by secondary bacterial respiratory infection, thereby leading to great economic losses in the horse-breeding industry. In Brazil, equine influenza outbreaks were first reported in 1963 and studies on hemagglutination antibodies against viral subtypes in Brazilian horses have been conducted since then. The objective of the present review was to present the history of the emergence of EIV around the world and in Brazil and the studies that have thus far been developed on EIV in Brazilian equines...

O vírus da influenza equina (EIV) (H3N8 e H7N7) é o agente causador da influenza equina, ou gripe equina. O subtipo viral H7N7 é considerado como mundialmente extinto desde 1980. Os animais afetados têm sintomas respiratórios característicos que podem ser agravados por uma infecção respiratória bacteriana secundária causando grandes prejuízos no ramo equestre. No Brasil, os surtos da EI têm sido relatados desde 1963 e desde então vem sendo efetuados estudos sobre a presença de anticorpos hemaglutinantes contra os subtipos virais nos equídeos brasileiros. O presente artigo tem o objetivo de apresentar um histórico sobre o surgimento do EIV no mundo e no Brasil destacando os estudos conduzidos no Brasil até o momento acerca da infecção pelo EIV nos equídeos brasileiros...

Protective roles of free avian respiratory macrophages in captive birds

In the mammalian lung, respiratory macrophages provide front line defense against invading pathogens and particulate matter. In birds, respiratory macrophages are known as free avian respiratory macrophages (FARM) and a dearth of the cells in the avian lung has been purported to foreordain a weak first line of pulmonary defense, a condition associated with high mortality of domestic birds occasioned by respiratory inflictions. Avian pulmonary mechanisms including a three tiered aerodynamic filtration system, tight epithelial junctions and an efficient mucociliary escalator system have been known to supplement FARM protective roles. Current studies, however, report FARM to exhibit an exceptionally efficient phagocytic capacity and are effective in elimination of invading pathogens. In this review, we also report on effects of selective synthetic peroxisome proliferator activated receptor gamma (PPAR γ) agonists on non phlogistic phagocytic properties in the FARM. To develop effective therapeutic interventions targeting FARM in treatment and management of respiratory disease conditions in the poultry, further studies are required to fully understand the role of FARM in innate and adaptive immune responses.

Aspergillus fumigatus from normal and condemned carcasses with airsacculitis in commercial poultry / Pesquisa de Aspergillus fumigatus em carcaças de frango de corte normais e condenadas por aerossaculite

Carcass inspection is important for the detection of certain diseases and for monitoring their prevalence in slaughterhouses. The objective of this study was to assess the occurrence of aspergillosis caused by Aspergillus fumigatus in commercial poultry, through mycological and histopathological diagnosis, and to verify the causal association between the aspergillosis diagnosis criteria and condemnation due to airsacculitis in broilers through a case-control study. The study was carried out with 380 samples. Lungs were collected from broilers that were condemned (95) or not condemned (285) due to airsacculitis directly from the slaughter line. Forty-six (12%) lung samples were positive for A. fumigatus in mycological culture. Among all samples, 177 (46.6%) presented histopathological alterations, with necrotic, fibrinous, heterophilic pneumonia; heterophilic pneumonia and lymphoid hyperplasia being the most frequent. Out of the 380 lungs analyzed, 65.2% (30) showed histopathological alterations and isolation of fungi. The statistical analysis (McNemar's chi-square test) indicated a significant association between the presence of histopathological lesions and the isolation of A. fumigatus. Mycological cultivation and histopathological diagnosis increase the probability of detecting pulmonary alterations in birds condemned by the Final Inspection System, which suggests that such diagnostic criteria can improve the assessment and condemnation of birds affected by airsacculitis.

Nos abatedouros, a inspeção das carcaças é fundamental para a detecção e monitoramento da prevalência de certas doenças. Os objetivos do trabalho foram avaliar a ocorrência de aspergilose causada por Aspergillus fumigatus em aves comerciais através do diagnóstico micológico e histopatológico e verificar a possibilidade de associação causal entre os critérios de diagnóstico de aspergilose e condenação por aerossaculite em frangos de corte através de um estudo de caso-controle. O estudo foi realizado com 380 amostras. Foram coletados pulmões de frangos condenados (95) e não condenados (285) por aerossaculite, diretamente na linha de abate de um frigorífico. Quarenta e seis (12%) amostras de pulmão foram positivas na cultura micológica. Do total de amostras, 177 (46,6%) apresentaram alterações histopatológicas, sendo os mais frequentes pneumonia fibrinoheterofílica necrótica, pneumonia heterofílica e hiperplasia linfóide. Do total de 380 pulmões analisados, 65,2% (30) apresentaram alterações histopatológicas e isolamento fúngico. A relação entre a presença de lesões histopatológicas e isolamento de A. fumigatus testada por McNemar indicou que houve associação significativa entre a presença de alterações histopatológicas e o isolamento de A. fumigatus. O cultivo micológico e o exame histopatológico aumentam as chances de se detectar alterações pulmonares em aves condenadas pelo Sistema de Inspeção Final do que nas aves normais, sugerindo que tais critérios de diagnóstico são eficazes para aprimorar a avaliação e condenação de aves por aerossaculite.

Occurrence of Chlamydophila felis in a cattery in Osasco city, São Paulo state / Ocorrência de Chlamydophila felis em um gatil na região de Osasco, São Paulo

Chlamydophila felis is associated with upper respiratory tract infections. In the present study, 31 cats from a noncommercial shelter located in Osasco, SP, Brazil, were examined. The cats presented with clinical manifestations, which were classified from grade 1 to 4, with 4 indicating severe manifestations. In total, 16.13% of the cats presented with grade 1 severity of clinical manifestations, 25.81% presented with grade 2, 38.71% presented with grade 3, and 19.35% presented with grade 4. PCR was used to detect C. felis in samples taken from the oral mucosa and ocular conjunctiva of both eyes using sterile, dry cotton swabs. Overall, 58% of the samples were positive for C. felis. Of these animals, none showed clinical manifestations that were classified as grade 1, whereas 5.56% of cats were classified as grade 2, 61.11% were classified as grade 3, and 33.33% were classified as grade 4. The median clinical manifestation intensity score for the first group was 3 and ranged from 2 to 4. In the second group not positive for C. felis, 38.45% of the animals (5/13) presented with manifestations classified as grade 1, 53.85% (7/13) were classified as grade 2, 7.69% (1/13) were classified as grade 3, and no animals were classified as grade 4. The median clinical manifestation intensity score for the second group was 2 and ranged from 1 to 3. In this study, there was a high occurrence of C. felis in animals with clinical manifestations.

A Chlamydophila felis está associada à infecção de trato respiratório superior. No presente estudo, foram utilizados 31 felinos de um gatil não comercial, localizado em Osasco/SP. Os gatos apresentavam manifestações clínicas, classificadas de 1 a 4, sendo 4 atribuído àqueles que apresentavam pior manifestação clínica. Foi observada a intensidade de manifestação clínica grau 1 em 16,13% dos gatos, a 2 em 25,81%, a 3 em 38,71% e a 4 em 19,35%. A detecção de C. felis foi realizada por técnica de PCR em amostras obtidas com suabes de algodão, seco e estéril, de mucosa oral e de conjuntiva ocular de ambos os olhos. Verificou-se que 58% das amostras para C. felis foram positivas, entre esses animais, nenhum apresentou manifestação clínica classificada como grau 1, o grau 2 foi observado em 5,56% dos gatos, 61,11% para o 3 e 33,33% dos animais apresentava a intensidade 4. Verificou-se que para o primeiro grupo a mediana dos escores de intensidade das manifestações clínicas observadas foi de 3, variando de 2 a 4. No segundo grupo, foi observado 38,45% (5/13) dos animais para a intensidade 1, 53,85% (7/13) para a 2 e 7,69% (1/13) para a 3, nenhum animal deste grupo apresentou o grau 4. Verificou-se para o segundo grupo, a mediana dos escores de intensidade das manifestações clínicas observadas foi de 2, variando de 1 a 3. Neste trabalho foi observada uma elevada ocorrência de C. felis em animais com manifestação clínica.

Ocorrência de Mannheimia haemolytica e de Pasteurella multocida em ovinos sadios e com enfermidade respiratória / Mannheimia haemolytica and Pasteurella multocida occurrence in healthy and affected lambs

Frequency of Mannheimia haemolytica and Pasteurella multocida in the respiratory tract of lambs in the region of Botucatu, SP, Brazil, was studied. Nasopharingeal and oropharingeal swabs were obtained from 262 animals: 180 from healthy and 82 from animals with respiratory diseases. M. haemolytica was the most prevalent (47 percent), followed by the association of M. haemolytica and P. multocida (27 percent), and P. multocida (11 percent). Animals with respiratory disease presented higher occurrence of P. multocida in the nasopharynx as compared to healthy animals (P<0.05). No significant difference in isolation rate of M. haemolytica, P. multocida, and association of these microorganisms in the oropharynx of healthy and affected animals was observed

Enfermidade gastroentérica e respiratória em bezerros inoculados com amostras brasileiras do vírus da Diarréia Viral Bovina tipo 2 (BVDV-2) / Gastroenteric and respiratory disease in calves inoculated with brazilian isolates of Bovine Viral Diarrhea virus type 2 (BVDV - 2)

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 infecçäo. Previamente à inoculaçäo, 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 inoculaçäo, os bezerros do grupo A apresentaram anorexia, depressäo, hipertermia, sinais de infecçäo 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-inoculaçäo. Ulceras e erosöes no trato digestivo (língua, n=4; esôfago, n=1; rúmen, n=1 e abomasso, n=3), edema pulmonar (n=4) e na mucosa do abomasso (n=3); equimoses e sufusöes na serosa do baço (n=2), no rúmen, no intestino delgado e no ceco (n=1), no coraçäo (n=1) e na mucosa da bexiga (n=1) e intussuscepçäo intestinal (=1) foram os achados macroscópicos mais marcantes. Ulceras e erosöes, acompanhadas de infiltrado mononuclear na mucosa e submucosa do trato digestivo e depleçäo linfóide nos linfonodos e placas de Peyer, foram as alteraçöes microscópicas mais freqüentes. O vírus foi detectado em vários tecidos e órgäos. 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 Peye e baço. Os animais do grupo B apresentaram depressäo, hipertermia, sinais moderados de infecçäo respiratória e digestiva, ulceraçöes 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 infecçäo foram mais severas nos animais mais jovens.

Prevalence of porcine reproductive and respiratory syndrome virus, porcine circovirus type 2 and porcine parvovirus from aborted fetuses and pigs with respiratory problems in Korea

Porcine reproductive and respiratory syndrome virus(PRRSV)0, porcine circovirus type 2(PCV-2) and porcine parvovirus (PPV)0 infections were investigated as possible causes of the postweaning multisystemic wasting syndrome(PMWS). Specific primers for RT-PCR and PCR were designed for the differential detection of PRRSV, PCV-2 and PPV. Using PCR, these viruses were detected in homogenized tissue samples from pigs that had respiratory of reproductive problems in the time period between 1998 and 2000; the overall prevalences were: PRRSV 31.4%, PCV-2 46.5%, and PPV 8.1%. PCV-2 was also detected in aborted fetal tissues.