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1.
To investigate the epizootic of swine influenza virus(SIV), 60 nasal swabs were collected from a clinical cases of pig farm in Tai'an City, Shandong Province of China in April 2017. SIV was isolated by inoculating into 10-day-old Special Pathogen Free embryonated eggs and the whole genome was sequenced. An H1N1 subtype SIV was isolated and designated as A/swine/Shandong/TA04/2017(H1N1). Phylogenetic analysis showed that apart from the polymerase A(PA) fragment belonging to the 2009 pandemic H1N1 branch, seven genome segments belonged to avian-like H1N1 influenza virus lineage. The cleavage site sequence of the hemagglutinin(HA) protein was PSIQSR↓G, which is a typical molecular biological characteristic. Five potential N-glycosylation sites(N14, N26, N277, N484 and N543) were found in the HA gene. To further investigate the epidemiology of SIV in this farm, the 995 serum samples were assessed with EAH1N1 2009 pandemic H1N1 and H3 N2 antigens. The results showed that the total positive rate was 65.43%. The positive rates of single virus infection detected by EAH1N1, 2009 pdmH1N1 and H3 N2 for serum HI(Hemagglutination inhibition) were 48.35, 30.85 and 7.47%, respectively. The results showed that SIV in Shandong Province has been reassorted in some segments and the SIV-positive rate was high on the SIV outbreak farm. These data provide evidence of an epizootic of SIV.  相似文献   
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Surveillance of hepatitis E virus (HEV) in risk groups is an important strategy to monitor its circulation pattern and to timely detect changes thereof. The aims of this cross-sectional study were to estimate the prevalence of HEV infections in pigs and humans from different regions of the country, to identify risk factors for increasing anti-HEV IgG prevalence and to characterize HEV strains. The presence of anti-HEV antibodies was assessed by commercial ELISA in serum samples from the general population, farm and slaughterhouse employees, as well as pigs sampled in the three regions of Cuba from February to September 2016. Overall, individuals with occupational exposure to swine or swine products (70/248, 28.2%) were 4 times more likely to be seropositive compared to the general population (25/285, 8.7%; OR: 4.18; p < .001). Within the risk group, risk factors included age, number of years working in a professional activity with direct exposure to swine, geographic region and distance between residence and closest professional swine setting, while wearing gloves had a protective effect. Prevalence of total anti-HEV antibodies in swine was 88.2% (165/187) and HEV RNA was detected by real-time RT-PCR in 9.2% (16/173) swine stools. All HEV strains sequenced clustered within genotype 3. Some strains clearly belonged to subtype 3a, while another group of strains was related with subtypes 3b and 3 k but partial HEV sequences did not allow unequivocal subtype assignment. These findings suggest that the high HEV exposure in Cuban individuals with swine-related occupations could be due to enzootic HEV in certain regions, direct contact with infectious animals or their products as well as environmental contamination.  相似文献   
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为了解莆田地区猪圆环病毒病的流行状况,2013—2014年间在莆田笏石、埭头、灵川、仙游地区等部分养猪场(户)共采集了322份未经PCV2疫苗免疫的猪血清样本,采用ELISA(酶联免疫吸附试验)方法对送检血清样品进行PCV2抗体水平检测。结果表明,322份被检血清中检出117份阳性血清,总阳性率为36.33%,其中以6~12周龄的小猪感染率最高,阳性率为55.56%。说明猪圆环病毒病在莆田市多数猪场中存在。  相似文献   
5.
Canine mammary gland tumour (MGT) is the most common neoplasm in female dogs and has similar biological characteristics to human MGT. Spontaneous canine MGT is a more attractive clinical model in oncological research than that of the murine experimental model. Tumour‐associated antigens (TAAs), which are produced in tumour cells, are applied as tumour markers, tumour vaccine antigens and molecular targets of therapeutic drugs. In this study, we have primarily identified 13 different TAAs of canine MGT by serological immunoscreening of cDNA expression library. The results of serological mini‐arrays of identified antigens showed that CCDC41 antigen specially reacted with 35% of sera from MGT‐dogs and did not react with control sera. We also found that HSPH1 mRNA expression levels increased significantly in MGT tissues. These findings will contribute to the development of diagnostic technologies and translational target therapies for dogs. Clinical relevance : HSPH1, which is strongly expressed in the tumour tissue, will be a possible vaccine antigen of canine MGT.  相似文献   
6.
The seroprevalence of Salmonella spp., pathogenic Yersinia spp., Toxoplasma gondii and Trichinella spp. was studied in 1353 finishing pigs from 259 farms that were allocated according to farm types: large fattening farms (≥1000 pig places), small fattening farms (< 1000 pig places) and farrow‐to‐finish farms. The antibodies were analysed with commercial ELISA kits in meat juice samples that were collected at Finnish slaughterhouses. Salmonella antibodies were rare (3% of pigs, 14% of farms) when the cut‐off optical density (OD) value 0.2 was used. Antibodies to pathogenic Yersinia spp. and T. gondii were detected in 57% of pigs and 85% of farms (OD ≥0.3) and in 3% of pigs and 9% of farms (OD ≥0.15), respectively. No antibodies to Trichinella spp. were detected (OD ≥0.3). The European Food Safety Authority (EFSA) considers Salmonella spp., Yersinia enterocolitica, T. gondii and Trichinella spp. as the most relevant biological hazards in the context of meat inspection of pigs. The seroprevalence of these important zoonotic pathogens was low in Finland, except that of Yersinia. The seroprevalence of Toxoplasma was significantly higher in pigs originating from small‐scale fattening farms (P < 0.05). Strong positive correlation was observed at the animal level between Salmonella and Yersinia seropositivity and between Salmonella and Toxoplasma seropositivity (P < 0.05). We suggest that these results reflect the level and importance of biosecurity measures applied on the farms. Meat juice serology at slaughter is a useful tool for targeting measures to control these pathogens. The information obtained from analyses should be used as part of the food chain information (FCI).  相似文献   
7.
马铃薯Y病毒(Potato virus Y,PVY)是世界范围内对茄科属植物造成影响的重要病毒,为了解PVY对新疆加工番茄的危害,本文采集205份加工番茄样品进行血清学检测,结果 PVY~O、PVY~(O\N\C)、PVY~N检出率分别为20%、18.05%和0%,且PVY不同株系总检出率达24.9%。根据血清学检测结果,在苋色藜(Chenopodium amaranticolor)上进行单斑分离获得2个PVY分离物S1-10、S2-12,其基因组序列分析结果显示,S1-10分离物是PVY~O与PVY~N的重组体,属于PVY~(N∶O)株系,S2-12属于PVY~O株系。本研究表明新疆加工番茄上的PVY主要为PVY~(N∶O)和PVYO株系。  相似文献   
8.
Rabies is endemic in wildlife or domestic carnivore populations globally. Infection of domestic dogs is of particular concern in many areas. In regions where domestic animals are at risk of exposure to rabies virus, dogs should be routinely vaccinated against rabies to protect both pet and human populations. Many countries require demonstration of an adequate level of serum rabies neutralizing antibodies to permit entry of dogs during international travel. We analysed rabies titres of dogs seeking travel certification in Israel to assess demographic and vaccine history factors associated with antibody titres below the acceptable threshold for travel certification. Having received only one previous rabies vaccination and a longer duration since the most recent vaccination was received were primary risk factors for not achieving an adequate rabies virus neutralizing antibody titre for travel certification. These risk factors had stronger effects in younger animals, but were consistent for dogs of all ages. In particular, these findings reiterate the importance of administering at least two rabies vaccinations (the primo vaccination and subsequent booster) to ensure population‐level protection against rabies in dogs globally.  相似文献   
9.
A sero-epidemiological study of cats and dogs in the Launceston area of Tasmania, Australia was undertaken to determine the prevalence of antibodies to spotted fever group (SFG) rickettsiae. Results showed that 59% of cats and 57% of dogs were positive for antibodies, but there was no correlation between the animal's health and seropositivity at the time of testing, suggesting that rickettsial exposure is unrelated to ill-health in these two species of domestic animals.  相似文献   
10.
应用正向间接血凝试验对东莞市采集的977份犬血清和126份猫血清进行了衣原体抗体检测,检测结果为犬抗体阳性28份,抗体阳性率2.87%;其中散养犬只抗体阳性数24份,抗体阳性率2.96%,三鸟批发市场肉用犬抗体阳性数3份,抗体阳性率3.61%,犬养殖抗体阳性数1份,抗体阳性率1.2%。猫抗体阳性3份,抗体阳性率2.38%。结果表明我市的犬、猫和外地输入东莞市的肉用犬都存在衣原体的感染。  相似文献   
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