- 阅读权限
- 10
- UID
- 60877
- 积分
- 52
- 主题
- 0
- 帖子
- 52
- 精华
- 0
- 经验
- 52 点
- 金币
- 282 元
- 注册时间
- 2014-11-3
该用户从未签到 - 帖子
- 52
- 精华
- 0
- 经验
- 52 点
- 金币
- 282 元
- 注册时间
- 2014-11-3
|
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)不显示任何的证据,尽管其影响被观察到的是在一些地区“减弱”。我们知道一些环境似乎更一致的生产率比其他人,尽管很难得出全面广泛的结论。目前正在努力描述可能存在共同的特征来解释为什么有些什么影响,而其他的则不能。我不相信这将解决这个问题,但如果我们幸运的话可能会提供一些额外的解释这些模式,已经很明显的领域。如果你想要更多的信息,问。
弧菌菌株(如做许多(如果不是大多数的细菌菌株)容易交换遗传物质从而不断发展的。这是不幸的,但在大多数领域的影响,没有通用的协议,实际发生的是什么。的事实在太多虾世界的农业地区,但很少注意生物安全,虾是不考虑他们可能携带的风险,公司正在推动non-proven伪科学的解决方案,等没有帮助。很有可能,这个问题将继续蔓延。许多农民其实不知道为什么他们的虾死亡。
考虑到不同看法正在发生什么事情,我认为许多被报道是类似于战争的报道,起源于雾。事实是有,但它不是那么糟糕,或者是好的,因为它被描述。弧菌(年代)负责AHPNS很可能是选择的方法,对预防这种性质的问题被广泛提倡。
天真地认为细菌问题是相对简单的与病毒问题的一部分。弧菌病由于许多不同的物种/株弧菌是一种常见的疾病影响虾农民无处不在。弧菌属的回收甲壳素至关重要。试图消除他们在户外环境中(实际上即使在室内环境),在我看来,一个傻瓜的使命。进一步延续的神话,细菌在某些方面总是坏。有证据表明,压力会是这种疾病的一个关键因素的过程(如在大多数疾病过程)是bio-amplification(这实际上可能是控制影响的关键),氯消毒虾池的广泛使用,而不是使用一个有条不紊的池塘准备的过程,允许一个相对成熟和平衡的生态发展,部分(很大程度上)负责的问题。机制(s)的菌株产生的疾病变得理解选项,这个时候可能变得明显不明显。目前尽管农民会更好欣赏很多,有科学养殖,忽略它他们做了自己的危险。我不会赌这个更改任何时间在不久的将来。
疾病是自然的。没有不是。单一生产环境,不能占的角色压力和临界性质的自然微生物过程保持平衡是非常脆弱的。没有谈论可持续生产会阻止这种性质的问题。而负责任的做法可能会降低这些华丽的问题在未来的发展,这一过程的本质可以确保我们将继续看到周期性严重的潜在的行业广泛疾病问题到可预见的未来。
|
|
[复制链接]
本站会员
发表于 2014-11-4 10:23:53
匿名卡
显身卡
狗仔卡
发表于 2014-11-4 10:33:55
