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1.
V. Leroy Young Mary K. Seaton Christine A. Feely Cynthia Arfken Dorothy F. Edwards Carolyn M. Baum Samuel Logan 《American journal of industrial medicine》1995,27(3):419-431
On-site testing of 157 poultry processors disclosed that 50% had three or more abnormal upper extremity findings out of a total of 22 possibles. The average worker had five to six abnormal findings. Impaired pinch strength, decreased vibration sensitivity in the fingertips, and reports of current numbness were the most prevalent. Of workers with signs, 25% reported no symptoms, whereas only 8% of workers reported symptoms but had no signs. The investigators concluded that this measurement method has utility for assessments of worker populations to determine prevalence of CTDs and, potentially, for preclinical detection of these disorders to permit early intervention, reduce medical costs, and minimize disability. The need for accurate measurement to enhance early detection and prevention is discussed. 相似文献
2.
ABSTRACT Coronaviruses (CoVs) mainly cause enteric and/or respiratory signs. Mammalian CoVs including COVID-19 (now officially named SARS-CoV-2) belong to either the Alphacoronavirus or Betacoronavirus genera. In birds, the majority of the known CoVs belong to the Gammacoronavirus genus, whilst a small number are classified as Deltacoronaviruses. Gammacoronaviruses continue to be reported in an increasing number of avian species, generally by detection of viral RNA. Apart from infectious bronchitis virus in chickens, the only avian species in which CoV has been definitively associated with disease are the turkey, pheasant and guinea fowl. Whilst there is strong evidence for recombination between gammacoronaviruses of different avian species, and between betacoronaviruses in different mammals, evidence of recombination between coronaviruses of different genera is lacking. Furthermore, the recombination of an alpha or betacoronavirus with a gammacoronavirus is extremely unlikely. For recombination to happen, the two viruses would need to be present in the same cell of the same animal at the same time, a highly unlikely scenario as they cannot replicate in the same host! 相似文献
3.
Regiane R. Santos Ajay Awati Petra J. Roubos-van den Hil Theo A. T. G. van Kempen Monique H. G. Tersteeg-Zijderveld Peter A. Koolmees 《Avian pathology》2019,48(6):582-601
ABSTRACTWe evaluated a blend of medium-chain fatty acids (MCFA), organic acids, and a polyphenol antioxidant on gut integrity. Eighty Ross Broilers were exposed to 20–22°C (control – normothermic) or to 35–39.5°C (heat stress) for eight hours a day for a period of 1 or 5 days. Birds were fed a standard diet, or a diet supplemented with the test blend. Thereafter, birds were euthanized, and intestinal sections were excised for morphological, morphometric and gene expression analyses. Blood samples were collected for glucose-6-phosphate dehydrogenase (G6PD), glutathione peroxidase (GSH-Px) activity and trolox equivalent antioxidant capacity (TEAC) determination. Heart and liver tissues were used to quantify the expression of heat shock proteins 60 and 70 (HSP60 and HSP70, respectively) and inhibitor of kappa light chain gene enhancer in B cells alpha (IKBA). The jejunum was the most sensitive intestinal section, where heat stress modulated the expression of HSP70, of the inflammatory markers IKBA, interleukin 8 (IL-8), interferon gamma (IFNγ), and toll-like receptor 4 (TLR4). Moreover, expression of tight junctions (CLDN1, ZO1 and ZO2) and nutrient transporters (PEPT1 and EAAT3) was modulated especially in the jejunum. In conclusion, the feed additive blend protected intestines during heat stress from the decrease in villus height and crypt depth, and from the increase in villus width. Especially in the jejunum, heat stress played an important role by modulating oxidative stress and inflammation, impairing gut integrity and nutrient transport, and such deleterious effects were alleviated by the feed additive blend.RESEARCH HIGHLIGHTS
Jejunum is the most sensitive intestinal segment during heat stress.
Heat stress affects the expression of tight junctions and nutrient transporters.
Feed management helps to alleviate the disturbances caused by heat stress.
A blend of MCFA, organic acids and a polyphenol protects broilers under heat stress.
4.
Mattias Delpont Manon Racicot Andr Durivage Lucie Fornili Jean‐Luc Guerin Jean‐Pierre Vaillancourt Mathilde C. Paul 《Transboundary and Emerging Diseases》2021,68(1):51-61
Biosecurity is crucial for infectious disease prevention, more importantly in the absence of vaccination. The need for improving the implementation of biosecurity practices was highlighted in French duck farms following the 2016–2017 H5N8 Highly Pathogenic Avian Influenza (HPAI) epidemic. Farmers have multiple reasons for not implementing biosecurity practices: external (time, money) and internal (socio‐psychological). The purpose of this study was to determine how sets of socio‐psychological factors (i.e. knowledge on biosecurity and avian influenza transmission, attitudes, personality traits, social background) affect the adoption of on‐farm biosecurity practices. Biosecurity practices and socio‐psychological determinants were assessed during 127 duck farm visits, in South West France, using both questionnaires and on‐farm observations. Factorial analysis of mixed data (FAMD) and hierarchical clustering analysis (HCA) identified three groups of farmers with different socio‐psychological profiles: the first group was characterized by minimal knowledge, negative attitudes towards biosecurity, little social pressure and a low level of conscientiousness. The second group was characterized by more extensive experience in poultry production, higher stress and social pressure. The third group was characterized by less experience in poultry production, better knowledge and positive attitudes towards biosecurity, increased self‐confidence and orientation towards action. The first group had a significantly lower adoption of biosecurity measures than the two other groups. A better understanding of the factors involved in farmers' decision‐making could improve the efficiency of interventions aiming at improving and maintaining the level of on‐farm biosecurity in the duck industry. 相似文献
5.
目的:以商售 Charm 细菌四环素族受体与四环素族的特异性结合反应为基础,应用其对活体禽类动物血清中四环素族抗生素残留总量进行快速筛选,重点对方法的灵敏度、选择性、基质影响和准确性等进行综合评价。方法:血清经缓冲液稀释,其中的四环素族抗生素残留与~3H 标记的金霉素竞争结合特异性细菌受体。竞争反应温育时间5 min,温度35℃。3300r·min~(-1),5 min 离心分离倾去未结合的游离化合物,复合物沉淀用水溶解,加入闪烁液混匀后放置1 min,进行[~3H]通道的60s 液体闪烁计数。结果:在大于95%的置信水平,血清中四环素、土霉素和金霉素的检测低限分别为80,55,15μg·L~(-1);样本测试表明筛选水平为200μg·L~(-1)时,假阴性率为0,阳性检出结果中假阳性率不超过15%。结论:与色谱法相比,其快速、灵敏、选择性高,可对活体禽类动物血清中四环素族残留物进行高通量筛选。 相似文献
6.
Human influenza A (H5N1) cases, urban areas of People's Republic of China, 2005-2006 总被引:1,自引:0,他引:1
Yu H Feng Z Zhang X Xiang N Huai Y Zhou L Li Z Xu C Luo H He J Guan X Yuan Z Li Y Xu L Hong R Liu X Zhou X Yin W Zhang S Shu Y Wang M Wang Y Lee CK Uyeki TM Yang W;Avian Influenza HN study Group 《Emerging infectious diseases》2007,13(7):1061-1064
We investigated potential sources of infection for 6 confirmed influenza A (H5N1) patients who resided in urban areas of People's Republic of China. None had known exposure to sick poultry or poultry that died from illness, but all had visited wet poultry markets before illness. 相似文献
7.
在受检的10种常见动物中发现,鹌鹑、猫、狗、猪、鸡、鸭和牛的胆汁中弯曲菌带菌率分别为23.64%、14.29%、7.14%、6.64%、5.88%、5.55%和3.63%。体外实验证明,弯曲菌在胆汁中可存活4~7周。动物肠内容物的带菌率普遍高于同种动物的胆汁带菌率。进一步提示,这些家畜、家禽是弯曲菌的重要传染源。 相似文献
8.
Timm Harder Sebastian Maurer-Stroh Anne Pohlmann Elke Starick Detlef H?reth-B?ntgen Karin Albrecht Gunter Pannwitz Jens Teifke Vithiagaran Gunalan Raphael T.C. Lee Carola Sauter-Louis Timo Homeier Christoph Staubach Carola Wolf Günter Strebelow Dirk H?per Christian Grund Franz J. Conraths Thomas C. Mettenleiter Martin Beer 《Emerging infectious diseases》2015,21(5):860-863
Highly pathogenic avian influenza (H5N8) virus, like the recently described H5N8 strain from Korea, was detected in November 2014 in farmed turkeys and in a healthy common teal (Anas crecca) in northeastern Germany. Infected wild birds possibly introduced this virus. 相似文献
9.
Hyun-Mi Kang Eun-Kyoung Lee Byung-Min Song Jipseol Jeong Jun-Gu Choi Joojin Jeong Oun-Kyong Moon Hachung Yoon Youngmi Cho Young-Myong Kang Hee-Soo Lee Youn-Jeong Lee 《Emerging infectious diseases》2015,21(2):298-304
An outbreak of highly pathogenic avian influenza, caused by a novel reassortant influenza A (H5N8) virus, occurred among poultry and wild birds in South Korea in 2014. The aim of this study was to evaluate the pathogenesis in and mode of transmission of this virus among domestic and wild ducks. Three of the viruses had similar pathogenicity among infected domestic ducks: the H5N8 viruses were moderately pathogenic (0%–20% mortality rate); in wild mallard ducks, the H5N8 and H5N1 viruses did not cause severe illness or death; viral replication and shedding were greater in H5N8-infected mallards than in H5N1-infected mallards. Identification of H5N8 viruses in birds exposed to infected domestic ducks and mallards indicated that the viruses could spread by contact. We propose active surveillance to support prevention of the spread of this virus among wild birds and poultry, especially domestic ducks. 相似文献
10.
A novel H10N8 influenza A virus has been detected in three humans in China since December 2013. Although this virus was hypothesized to be a novel reassortant among influenza viruses from wild birds and domestic poultry, its evolutionary path leading to human infection is unknown. Sporadic surveillance at the live poultry market (LPM) suspected to be the source of infection for the first H10N8 patient has shown a gradual increase in influenza virus prevalence culminating with a predominance of H10N8 viruses. Influenza viruses detected in the LPM up to 8 months prior to human infection contributed genetic components to the zoonotic virus. These H10N8 viruses have continued to evolve within this LPM subsequent to the human infection, and continuous assessments of these H10N8 viruses will be necessary. Serological surveillance showed that the virus appears to have been present throughout the LPM system in Nanchang, China. Reduction of the influenza virus burden in LPMs is essential in preventing future emergence of novel influenza viruses with zoonotic and pandemic potential. 相似文献