弯曲杆菌 Campylobacter-----stress hormone noradrenalin

食用冷冻禽肉会降低食物中毒风险
http://www.cyol.net 2009-07-17
　 本报讯 据英国布里斯托大学网站报道，该校最新研究表明，当禽类饱受惊恐等压力折磨时，其体内的弯曲杆菌会更具进攻性。因此，相较于经过长途运输后宰杀的肉禽来讲，也许冷冻的禽肉相对更安全一些。

　　弯曲杆菌在鸡肉中比较常见，英国每年会有大约40万例由弯曲杆菌引起的食物中毒病例。一直以来，人们普遍认为不当的烹饪方式是导致禽肉食物中毒的重要原因。过去针对弯曲杆菌的研究都没有考虑到生产环境的影响，不能反映最真实的情况。而许多研究都表明，在经过长距离运输后，肉食动物肠道内的弯曲杆菌水平要远高于农场中的动物。

　　布里斯托大学临床兽医学系的汤姆·汉弗莱教授领导的研究小组对肉鸡体内弯曲杆菌的行为模式进行了仔细的研究，结果发现，压力下肉鸡体内弯曲杆菌水平增高与应激激素去甲肾上腺素的释放有关。这种激素会促进弯曲杆菌的生长繁殖，使其变得更具活力和侵略性，从而导致其毒性致病能力的提高。进一步研究表明，弯曲杆菌还会与动物肠道内的其他生物体相互作用，从而变得更具感染性。

　　汉弗莱教授指出，英国禽类产业一直在努力控制弯曲杆菌，而产学研结合进行研究显得至关重要。他们的研究有助于禽肉生产厂商在生产环节对有毒细菌进行控制，使禽肉更安全，从而减少食物中毒病例。 (刘海英)

Chilled-out animals: a lower risk for food poisoning

Press release issued 7 July 2009

Food poisoning bacteria become more invasive in animals that are stressed, according to new research from the University of Bristol in collaboration with the UK poultry industry. The results will be presented at the Society for Applied Microbiology summer conference in Manchester tomorrow [8 July].

Led by Professor Tom Humphrey from the University’s Department of Clinical Veterinary Science, the research examined the behaviour of Campylobacter in chickens, of which there are approximately 400,000 cases of Campylobacter food poisoning in the UK each year.

Improperly cooked poultry is an internationally important infection vehicle, particularly because this organism can be found in chicken muscle. Studies on bacteria like Campylobacter are traditionally carried out in conditions which may not reflect the production environment. Research in many countries has shown that after transport, levels of bacteria like Campylobacter are higher in the gut of food animals than on the farm. Work at Bristol has demonstrated that this may be associated with the release of the stress hormone noradrenalin. This hormone makes Campylobacter grow more quickly, become highly motile and invasive, leading to an increase in its ability to cause disease - its virulence.

A further finding in the studies at Bristol is that Campylobacter can interact with other organisms in the gut of food animals. When this happens it can become even more infective. The results of this study provide vital information to enable the control of infection in the production environment, making chicken safer and decreasing cases of food poisoning.

Professor Humphrey said: “The UK poultry industry is working hard to control Campylobacter. It is essential that this effort is supported by UK scientists and that research involves industry and is relevant to commercial production.”

Professor Humphrey will be presenting his work at 14.00 BST on Wednesday 8 July 2009 at the Geoffrey Manton Building of Manchester Metropolitan University.