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981.
982.
983.
Habronemiasis, otherwise known as summer sores, is a parasitic disease of horses, donkeys and other equids, commonly encountered in subtropical and tropical regions. It occurs as a result of nematode infestation of the skin and typically manifests as ulcerative granulating lesions or masses. Habronema muscae, Habronema microstoma and Draschia megastoma are the usual invaders, usually transmitted by house flies, face flies and stable flies. In this case report, an eosinophilic granuloma on the urethral process of a 15-year-old gelding is presented, followed by successful surgical excision without further medical treatment. To the authors’ knowledge, equine eosinophilic granuloma on the urethral process associated with habronemiasis has not previously been documented in southern Europe and should be considered as a potential differential diagnosis for penile masses.  相似文献   
984.
985.
Following a series of H5N1 cases in chickens and birds in a few states in Malaysia, there was much interest in the influenza A viruses subtypes that circulate among the local pig populations. Pigs may act as a mixing vessel for avian and mammal influenza viruses, resulting in new reassorted viruses. This study investigated the presence of antibodies against influenza H1N1 and H3N2 viruses in pigs from Peninsular Malaysia using Herdcheck Swine Influenza H1N1 and H3N2 Antibody Test Kits. At the same time, the presence of influenza virus was examined from the nasal swabs of seropositive pigs by virus isolation and real time RT-PCR. The list of pig farms was obtained from the headquarters of the Department of Veterinary Services, Malaysia, and pig herds were selected randomly from six of 11 states in Peninsular Malaysia. A total of 727 serum and nasal swab samples were collected from 4- to 6-month-old pigs between May and August 2005. By ELISA, the seroprevalences of swine influenza H1N1 and H3N2 among pigs were 12.2% and 12.1% respectively. Seropositivity for either of the virus subtypes was detected in less than half of the 41 sampled farms (41.4%). Combination of both subtypes was detected in 4% of all pigs and in 22% of sampled farms. However, no virus or viral nucleic acid was detected from nasal samples. This study identified that the seropositivity of pigs to H1N1 and H3N2 based on ELISA was significantly associated with factors such as size of farm, importation or purchase of pigs, proximity of farm to other pig farms and the presence of mammalian pets within the farm.  相似文献   
986.
Municipal waste is a potential source of infection for Toxoplasma gondii as it may contain contaminated meat with parasite tissue cysts and cat excrement with parasite oocysts. Therefore, we sought to determine the prevalence of T. gondii infection and associated characteristics in two populations exposed to municipal solid waste in Durango, Mexico. Ninety waste pickers and 83 waste workers of Durango City, Mexico were examined for T. gondii infection. They were tested for anti-T. gondii IgG and IgM antibodies using enzyme-linked immunoassays. In addition, socio-demographic and behavioural characteristics from each participant were obtained. Nineteen (21.1%) of the 90 waste pickers and seven (8.4%) of the 83 waste workers were positive for anti-T. gondii IgG antibodies. The difference in prevalence among the groups was statistically significant (P =0.03). Waste pickers aged 31-50 years showed a significantly higher prevalence (40.9%) than waste workers of the same age group (2.9%, P < 0.001). Anti-T. gondii IgM antibodies were found in two (2.2%) of the waste pickers but in none of the waste workers. The seroprevalence of T. gondii was significantly higher in workers of the waste transfer station (25.0%) than in drivers or helpers of waste vehicles (2.5%) (P =0.03). Multivariate analysis showed that T. gondii infection was associated with consuming food found in the garbage [adjusted odds ratio (OR) = 4.4; 95% confidence interval (CI) 1.6-11.8] and with lack of education (adjusted OR = 3.2; 95% CI 1.1-8.8). From this study, we conclude: (i) waste pickers may represent a risk group for T. gondii infection; (ii) lack of education might be a contributing factor for T. gondii infection; (iii) the higher the exposure to garbage, the higher the seroprevalence of T. gondii infection; (iv) Eating food products from the garbage may represent an important route for T. gondii infection.  相似文献   
987.
刘凯  穆月英  韩婷 《中国蔬菜》2018,1(2):63-70
基于ARCH类模型,采用2007年6月至2015年11月北京市蔬菜总体按月平均价格数据,对蔬菜市场价格波动引起的风险集簇性、"杠杆效应"等特征进行了系统分析。主要研究结论是,蔬菜价格波动具有ARCH效应,蔬菜价格受前期波动的正向影响,但价格冲击对其价格波动的影响持续时间比较短,价格波动具有高风险高回报的特征,且存在"杠杆效应"。最后,针对结论提出了相关政策建议。  相似文献   
988.
989.
试验应用统计过程控制(SPC)分析饲料生产中蛋白质原料配料保真现状,并对配料误差存在原因进行探讨,旨在为饲料企业配料质量管理提供借鉴。收集两家饲料厂(饲料厂A、B)2015年仔猪料中豆粕、鱼粉和膨化大豆3种蛋白质原料的配料设定值和实际称量值,应用单值-移动极差控制图和生产过程能力评价方法对蛋白质原料的配料保真现状进行分析。结果显示,饲料厂A豆粕、鱼粉和膨化大豆生产过程能力指数CPK分别为0.20、0.11和0.01,膨化大豆的配料保真度最差,且3种原料的配料实际称量值远高于设定值;饲料厂B豆粕、鱼粉和膨化大豆生产过程能力指数CPK分别为0.24、0.12和0.24,鱼粉的配料保真度最差,膨化大豆的配料过程存在失控情况;两家饲料厂的蛋白质原料配料误差均超过了饲料行业动态配料精度±0.3% FS的要求,配方保真性较差,需采取措施进行改进。综合分析两家饲料厂配方保真性差的原因是,配料秤工艺参数配置不合理,空中落料量和快慢进料量参数需进一步优化,饲料厂B存在人为操作错误。结果提示,应用SPC方法可较为直观的监控饲料配料过程,提升蛋白质原料的配料精度,减少蛋白质原料的浪费,降低饲料生产成本,从而提高饲料厂配料质量管理水平。  相似文献   
990.
Shiga toxin‐producing Escherichia coli (STEC) is a zoonotic pathogen of public health concern whose sources and transmission routes are difficult to trace. Using a combined source attribution and case–control analysis, we determined the relative contributions of four putative livestock sources (cattle, small ruminants, pigs, poultry) to human STEC infections and their associated dietary, animal contact, temporal and socio‐econo‐demographic risk factors in the Netherlands in 2010/2011–2014. Dutch source data were supplemented with those from other European countries with similar STEC epidemiology. Human STEC infections were attributed to sources using both the modified Dutch model (mDM) and the modified Hald model (mHM) supplied with the same O‐serotyping data. Cattle accounted for 48.6% (mDM) and 53.1% (mHM) of the 1,183 human cases attributed, followed by small ruminants (mDM: 23.5%; mHM: 25.4%), pigs (mDM: 12.5%; mHM: 5.7%) and poultry (mDM: 2.7%; mHM: 3.1%), whereas the sources of the remaining 12.8% of cases could not be attributed. Of the top five O‐serotypes infecting humans, O157, O26, O91 and O103 were mainly attributed to cattle (61%–75%) and O146 to small ruminants (71%–77%). Significant risk factors for human STEC infection as a whole were the consumption of beef, raw/undercooked meat or cured meat/cold cuts. For cattle‐attributed STEC infections, specific risk factors were consuming raw meat spreads and beef. Consuming raw/undercooked or minced meat were risk factors for STEC infections attributed to small ruminants. For STEC infections attributed to pigs, only consuming raw/undercooked meat was significant. Consuming minced meat, raw/undercooked meat or cured meat/cold cuts were associated with poultry‐attributed STEC infections. Consuming raw vegetables was protective for all STEC infections. We concluded that domestic ruminants account for approximately three‐quarters of reported human STEC infections, whereas pigs and poultry play a minor role and that risk factors for human STEC infection vary according to the attributed source.  相似文献   
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