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Misguided optimism? EMS is here to stay.
By Stephen Newman
Published on 25 June, 2014
EMS (AHPNS) is not showing any evidence of going away, although its impact has been observed as “waning” in some areas. We know that some environments seem to be more consistent in terms of productivity than others, although it is difficult to draw broad across the board conclusions. Currently efforts are under way to characterize what common features might be present to explain why some are affected and others are not. I do not believe that this is going to solve the problem, although if we are lucky it may shed some additional light on those patterns that are already apparent to those in the field. If you want more information, ask.
Vibrio strains (as do many if not most strains of bacteria) readily exchange genetic material thus they are constantly evolving. It is unfortunate, but in most of the areas that are being affected, there is no universal agreement as to what is actually occurring. The fact that in all too many shrimp farming areas of the world, little attention is paid to biosecurity, shrimp are moved without regard to what they may be at risk of carrying, companies are pushing non-proven pseudo scientific solutions, etc. does not help. It is highly likely that this problem will continue to spread. Many farmers actually have no idea why their shrimp are dying.
Given the varying opinions about what is currently happening, I would characterize a lot of what is being reported as being akin to the reporting that originates in the fog of war. The truth is there to be had, but it is not as bad, or as good, as it is being depicted. The vibrio(s) responsible for AHPNS may have been selected for by the very methodologies that have been widely advocated for preventing problems of this nature.
The naïve view that bacterial problems are relatively simple contrasted with viral problems is part of this. Vibriosis due to any of many different vibrio species/strains is a common disease affecting shrimp farmers everywhere. Vibrios are essential for the recycling of chitin. Trying to eliminate them in outdoor environments (and indeed even in indoor environments) is, in my opinion, a fool’s mission. It further perpetuates the myth that bacteria are in some way always bad. The evidence suggests that stress can be a critical factor in this disease process (as it is in most disease processes) as is bio-amplification (this may actually be the key to controlling the impact) and that the widespread use of chlorine to disinfect shrimp ponds, rather than the use of a methodical process of pond preparation that allows a relatively mature and well balanced ecology to develop, is partly (largely?) to blame for the problem. As the mechanism(s) by which the strains produce disease becomes understood options that are not apparent at this time may become evident. For the time being though farmers would be a lot better off appreciating that there is a science to aquaculture and that ignoring it is something that they have done at their own peril. I would not bet on this changing any time in the near future.
Disease is natural. Its absence is not. Monoculture production environments that fail to account for the role of stress and the critical nature of the natural microbial processes in maintaining a balance are highly vulnerable. No talk of sustainable production will prevent problems of this nature. While responsible practices might be able to mitigate the development of problems of this ilk in the future, the very nature of the process ensures that we will continue to see periodic severe potentially industry wide disease problems well into the foreseeable future.
EMS(AHPNS)不顯示任何的證據(jù),盡管其影響被觀察到的是在一些地區(qū)“減弱”。我們知道一些環(huán)境似乎更一致的生產(chǎn)率比其他人,盡管很難得出全面廣泛的結(jié)論。目前正在努力描述可能存在共同的特征來(lái)解釋為什么有些什么影響,而其他的則不能。我不相信這將解決這個(gè)問題,但如果我們幸運(yùn)的話可能會(huì)提供一些額外的解釋這些模式,已經(jīng)很明顯的領(lǐng)域。如果你想要更多的信息,問。
弧菌菌株(如做許多(如果不是大多數(shù)的細(xì)菌菌株)容易交換遺傳物質(zhì)從而不斷發(fā)展的。這是不幸的,但在大多數(shù)領(lǐng)域的影響,沒有通用的協(xié)議,實(shí)際發(fā)生的是什么。的事實(shí)在太多蝦世界的農(nóng)業(yè)地區(qū),但很少注意生物安全,蝦是不考慮他們可能攜帶的風(fēng)險(xiǎn),公司正在推動(dòng)non-proven偽科學(xué)的解決方案,等沒有幫助。很有可能,這個(gè)問題將繼續(xù)蔓延。許多農(nóng)民其實(shí)不知道為什么他們的蝦死亡。
考慮到不同看法正在發(fā)生什么事情,我認(rèn)為許多被報(bào)道是類似于戰(zhàn)爭(zhēng)的報(bào)道,起源于霧。事實(shí)是有,但它不是那么糟糕,或者是好的,因?yàn)樗幻枋觥；【?年代)負(fù)責(zé)AHPNS很可能是選擇的方法,對(duì)預(yù)防這種性質(zhì)的問題被廣泛提倡。
天真地認(rèn)為細(xì)菌問題是相對(duì)簡(jiǎn)單的與病毒問題的一部分。弧菌病由于許多不同的物種/株弧菌是一種常見的疾病影響蝦農(nóng)民無(wú)處不在。弧菌屬的回收甲殼素至關(guān)重要。試圖消除他們?cè)趹敉猸h(huán)境中(實(shí)際上即使在室內(nèi)環(huán)境),在我看來(lái),一個(gè)傻瓜的使命。進(jìn)一步延續(xù)的神話,細(xì)菌在某些方面總是壞。有證據(jù)表明,壓力會(huì)是這種疾病的一個(gè)關(guān)鍵因素的過程(如在大多數(shù)疾病過程)是bio-amplification(這實(shí)際上可能是控制影響的關(guān)鍵),氯消毒蝦池的廣泛使用,而不是使用一個(gè)有條不紊的池塘準(zhǔn)備的過程,允許一個(gè)相對(duì)成熟和平衡的生態(tài)發(fā)展,部分(很大程度上)負(fù)責(zé)的問題。機(jī)制(s)的菌株產(chǎn)生的疾病變得理解選項(xiàng),這個(gè)時(shí)候可能變得明顯不明顯。目前盡管農(nóng)民會(huì)更好欣賞很多,有科學(xué)養(yǎng)殖,忽略它他們做了自己的危險(xiǎn)。我不會(huì)賭這個(gè)更改任何時(shí)間在不久的將來(lái)。
疾病是自然的。沒有不是。單一生產(chǎn)環(huán)境,不能占的角色壓力和臨界性質(zhì)的自然微生物過程保持平衡是非常脆弱的。沒有談?wù)摽沙掷m(xù)生產(chǎn)會(huì)阻止這種性質(zhì)的問題。而負(fù)責(zé)任的做法可能會(huì)降低這些華麗的問題在未來(lái)的發(fā)展,這一過程的本質(zhì)可以確保我們將繼續(xù)看到周期性嚴(yán)重的潛在的行業(yè)廣泛疾病問題到可預(yù)見的未來(lái)。
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