看国外 | 后抗生素时代,如何解决生猪的细菌性肠道疾病?

看国外 2019-01-10 09:48:14

来源:WATTAgNet

How to fight bacteria related gut disorders in farm animals in the post-antibiotic era? Using phytogenics that interfere with the bacterial communication system is one of the solutions to do so.

在后抗生素时代,如何解决农场动物的细菌性肠道疾病?使用干扰细菌通讯系统的植物遗传学是其中一个解决方案。

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动物科学家Sandra Chamusco

You might have heard that bacteria communicate with each other using chemical words – their signalling molecules. Thereby, they use specific molecules as a language among the same species but can also communicate with other bacteria or even their hosts by release or recognition of different molecules, like the use of different languages.

你可能听说过,细菌使用化学物质 - 它们的信号分子 - 相互沟通。因此,它们使用特定分子作为同一物种中的一种语言,但也可以通过释放或识别不同分子与其他细菌甚至其宿主交流,就像我们使用不同语言。

Reducing the virulence of bacterial pathogens

减少细菌病原体的毒力

An important set of these ‘languages’ is called quorum sensing, which is used by bacteria to evaluate microbial populations and their conditions in their surroundings. According to the gathered information, they adapt their behaviour. This is essential for the optimal use of available resources, as individual bacteria might need to behave differently compared to being part of a group of the same kind. Besides this, many pathogenic bacteria use quorum sensing to switch from non-virulent to virulent. For example, it is used by enterotoxigenic E. coli (ETEC) to regulate their toxin production.

这些“语言”中的一组重要称为群体感应,细菌用它来评估微生物种群及其周围环境的状况。根据收集的信息,细菌再调整自己的行为。这对于可用资源的最佳利用至关重要,因为与作为同一类群体的一部分相比,个体细菌可能需要表现得不同。除此之外,许多致病菌使用群体感应从非毒力转变为毒力。例如,肠产毒性大肠杆菌(ETEC)使用它来调节毒素的产生。

Understanding such behaviour is therefore of practical importance, as ETEC strains are one of the most important causes of post-weaning diarrhoea in piglets. Active substances in phytogenic feed additives (PFAs) are now used to interfere with bacterial quorum sensing to reduce the virulence of bacterial pathogens like ETEC. As a result, the animals’ immune defences against bacterial infections are supported. This turns out to be an important pillar in fighting bacteria related gut disorders in farm animals in the post-antibiotic era.

因此,了解细菌的这种行为具有实际意义,因为ETEC菌株是造成仔猪断奶后腹泻的最重要病原菌之一。现在会使用植物性饲料添加剂(PFAs)中的活性物质来干扰细菌群体感应,以降低细菌病原体如ETEC的毒力,从而有利于动物对细菌感染的免疫防御。在后抗生素时代,这成为了解农场动物细菌性肠道疾病的重要支柱。

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The antioxidative activity of phytogenic feed additives depends on different molecular structures and acts in 2 different ways. Photo: Dreamstime

植物性饲料添加剂的抗氧化活性取决于不同的分子结构,并以两种不同的方式起作用

Synergistic effects of phytogenic actives protect the gut

植物活性物质的协同作用保护肠道

Ideally, animals will not encounter disease challenges. However, in practical conditions, they must deal with a wide range of different factors affecting their health status. PFAs are derived from plants and include herbs, spices, and extracts, offering a possibility to support animals in health challenging conditions. By carefully choosing appropriate combinations, they have a potential to exert synergistic effects by employing different modes of action.

理想情况下,动物不会生病。但是,在实际情况下,它们会面临各种理影响其健康状况的不同因素。植物性饲料添加剂来自于植物,包括草药、香料和提取物,可以帮助动物对抗健康问题。通过仔细选择适当的组合,它们有可能通过采用不同的作用方式发挥协同效应。

This is utilised in recent product development by combining different essential oils, flavonoids, and mucilages to support the piglet’s gut in its most stressful life phase – the weaning period. During the weaning period, the piglets’ digestive system and immune competence are subject to massive changes, leading to the vulnerability of the animals’ health. A brief introduction is given on some modes of action exerted by PFAs to help to protect the piglet and its gut during this time.

这被用于最近的产品开发中,通过精油、黄酮类和粘液的不同组合来帮助仔猪度过生命中应激最大的阶段 - 断奶期。在断奶期间,仔猪的消化系统和免疫能力发生了巨大的变化,因而健康状况很脆弱。以下简要介绍了植物性饲料添加剂在此期间保护仔猪及其肠道的一些作用方式。

Antioxidative and anti-inflammatory mode of action

抗氧化和抗炎作用方式

In addition to their quorum sensing inhibition capabilities, PFAs can support the intestinal integrity through their antioxidant properties. As the intestinal epithelium is only formed by a thin layer of epithelial cells, it is extremely vulnerable. A disruption of intestinal integrity leads to a “leaky gut,” which is determined by an increased permeability for food antigens and/or pathogens, thus burdening the immune system and reducing performance.

植物性饲料添加剂除了有群体感应抑制能力,还可以通过其抗氧化特性来维持肠道完整性。由于肠上皮仅由一层薄薄的上皮细胞形成,因此非常脆弱。肠道完整性的破坏会造成“肠道渗漏”,这是由食物抗原和/或病原体的渗透性增加引起的,从而加重免疫系统的负担并降低性能。

The antioxidative activity of PFAs depends on different molecular structures and acts in 2 different ways: either directly by capturing reactive oxygen species (ROS), or indirectly by stimulating the production of the animals own antioxidative enzymes. For example, superoxidase dismutase or glutathione peroxidase are 2 vital antioxidant enzymes that inactivate ROS. 

For both, it was shown, that certain PFAs can stimulate their production. As an excess of ROS leads to cell damage primarily to the intestinal epithelia, scavenging of those reactive molecules leads to fewer inflammations of the intestines, the increased integrity of the epithelial cell wall and thus improved performance.

植物性饲料添加剂的抗氧化活性取决于不同的分子结构,并以两种不同的方式起作用:直接捕获活性氧(ROS),或间接地刺激动物自身产生抗氧化酶。例如,超氧化酶歧化酶或谷胱甘肽过氧化物酶是二种使ROS失活的重要抗氧化酶。对于这两者,已经表明,某些植物性饲料添加剂可以刺激它们的产生。过量的活性氧造成的细胞损害主要是肠上皮细胞,清除这些反应性分子可以减少肠道炎症,增加上皮细胞壁完整性,从而改善性能。

In summary we can therefore say that active substances of PFAs work together to support the animals’ guts. Especially, the combination of specific essential oils, flavonoids, and mucilages offer benefits during the critical phase of weaning in the life of piglets.

总而言之,我们可以说,植物性饲料添加剂中的活性物质共同作用保护了生猪的肠道健康。 特别是,特定精油、黄酮类和粘液的组合在仔猪生命中的关键阶段——断奶期提供了益处。

Lessons learned

· Phytogenic feed additives derived from plants, including herbs, spices, and extracts, show synergistic effects if formulated properly

· Combinations of essential oils, flavonoids and mucilages can protect the gut of weaned piglets

· Phytogenic compounds are utilised to reduce the pathogenicity of certain intestinal pathogens via quorum sensing inhibition

· Anti-oxidative and anti-inflammatory effects support the functionality of the gut in post-weaning piglets

· Mucilages develop a thin layer on the intestinal mucous surface to prevent the attachment of intestinal pathogens, such as enterotoxigenic E. coli.

经验教训

•植物性饲料添加剂,包括草药、香料和提取物等,如果配制得当,可发挥协同效应

•精油、黄酮和粘液的组合可以保护断奶仔猪的肠道

•利用植物源化合物通过群体感应抑制可降低某些肠道病原体的致病性

•抗氧化和抗炎作用可维持断奶后仔猪肠道的功能

•粘液在肠粘膜表面形成薄层,以防止肠道病原体如肠毒素大肠杆菌的附着。

(文/爱猪网记者刘坤颖编译,爱猪网原创请勿转载)


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