Do you think stress causes Ich?

[Terry B]

It seems that it is a common opinion that stress causes Ich. I believe that a parasite causes Ich and no amount of stress can cause fish to become infected unless the parasite is in the system. Cryptocaryon irritans is an obligate pathogen. This means that this parasite must have a host fish or it will die. Facultative (oportunistic)pathogens can survive by feeding on things other than the fish. These pathogens include some parasites, most bacterial infections, and many fungus infections. Viral infections are obligate pathogens, but stress can still play a part. Stress is a much more important factor for infection with oportunistic pathogens than with obligate ones. Falcutative pathogens usually only infect fish that are weakened in some way. Vibrio (a type of bacteria), for example, could probably be found in most any aquarium, but it only causes problems when the water quality is poor or the fish is weakened by something like a wound. Anyone care to talk about it?
Terry B



[This message has been edited by Terry B (edited 09-22-2000).]

[jimmy n]

Agreed.

Ich is probably present in many home aquaria and just not evident because it's host in not overwhelmed with infection. When the host becomes stressed an outbreak of ich ensues. Not unlike humans, who have a multitude of endogenous flora, do not become sick unless they become susceptible. Good points, no arguements here.

Jim

[Terry B]

Hey Jimmy,
I see that you live in the area. It's nice to see someone local on this message board.
Terry B

[smpolyp]

You have a point. I never had ich in my reef for first 4 months that itwas up. But I had stress and did not know it. Forgot to turn on the pump on my reactor when I refilled my co2. About 3 days after the that I introduced a morish idol and a few days later almost all the fish had ick. The morish idol had the least of all the fish that had crpyt.Out of 2 fridmanis.2 true percs,black tang and 2 barber poles(never had crypt) the 2 barbers,one perc and the morish made it. I should have quarantined the morish for the full 2 weeks.

[Doug]

HI Terry,

This is an interesting topic for me. I have been sitting here for the last hour or so searching through the cobwebs in my brain trying to remember what caused Ich in my tanks before.

From what I can remember the only times that my fish got Ich was after I added a new fish to the tank. The tank would be fine for a period of time but then I would add a new fish and within days most of the fish in the tank would have it also. Now, I will admit that I have never used a Q-tank and have always added the fish right from the LFS to the tank.

Now the thing that I am wondering about is since I have added fish to my tanks over the last year or so (I haven't had to deal with Ich for over a year now) is it safe to assume that I have been very lucky that the fish I bought did not have Ich to start with or are my tanks just healthy enough to keep the Ich that they may be carrying from becoming a problem when adding a new fish.

As I was re-reading what I typed above something else came to front of my mind about stress. About 6 months ago I setup my 90g tank and moved all of the fish from my 2-29g tanks in to it. I moved many fish but there are 4 of them that have had more stress more than the others. The first two fish are a Flame Hawkfish (Neocirrhitus armatus) and Lawnmower Blenny (Salarias fasciatus). Both of these fish lived in the same tank for about 7 months and never showed any signs of aggression towards each other. After moving them into the 90g, which I am sure was stressful in itself, the Lawnmower started chasing the Flame Hawk every chance he had. Even though the Lawnmower could not catch the Hawk I am sure that the Hawk could not have had much more stress than this. The other two fish are a Tomato Clown (Amphiprion frenatus), Which I think is a direct descendant of Satan, and a Sailfin Tang (Zebrasoma veliferum). The Tomato Clown would chase the Sailfin back and fourth at every chance also. Now even with all of the stress of the move and all the chasing they did not show any signs of Ich. Now the Tomato did have a few wounds on his body from bumping the rockwork but all of them healed within days. I also feed the tank well each day and use Selcon at least weekly. Luckily for me and the fish the aggression ended about a month after the fish were in the tank. I would have to assume if stress could cause Ich there is a good chance that at least the Hawk and the Sailfin would have had it.

Now please remember that what I have typed above is just my own observations and that I have zero scientific proof to back it up but it does seem to make what you have said about Ich not being caused by stress correct.

Thanks for the interesting topic.

Doug

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Doug's Reef and Fish Page

Before you break the door down with an axe, try the doorknob first!

[Aquaman]

Terry

quote:

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It seems that it is a common opinion that stress causes Ich

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That statment seems kind of loaded,

quote:

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I believe that a parasite causes Ich

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DOH! Nobody I know has ever argued that! BUT, Perhaps a stressed fish is more susceptible to getting ick if the ick is already present in the tank. No expert here but seem to have read somewhere their is a dormant stage to ick?

Their are many illness that humans can get without stress, But many of these same illness can be contracted when said human is under extreme stress.

Did you know that when you contract chicken pox the virus mutates and remains dormant in your dorsal root ganglia nerves. Every person that has had chicken pox is susceptable to contracting shingles, You already have the latent virus in your system, but studies have shown that stress and a/or weakend immune system seems to be the most prevelent cause to the outbreak of shingles.

Both my coworker and my boss have contracted the shingles desease within the last year. and yes I can say having worked with both of them for the last 6 years and they both were under great stress this past year.

IMO Stress is a major factor in a fish contracting ick. My tank has had fish contract ick, I have done nothing other than remove the stress factor! which was a large temp swing during a normal 24hr period, The Ick has not returned to the fish for the last 3 months???



[This message has been edited by Aquaman (edited 09-22-2000).]

[Lobster]

Ummm... I think its pretty well known that the parasite is the "ich", and your fish cant catch ich unless the parasite already exists in the system or is introduced.

From what I have read and heard from others, fish have a resistance to the parasite (this is over-simplified Im sure). If a fish is living in unsatisfactory conditions (poor water, harassment by tankmates, malnutrition, etc) or has adjacent health issues, its resistance may be weakened.

My experience has been consistent with this thinking. I accept the fact that ich exists in my system, but I also believe fish should be resistant to it normally. If a fish is affected by the ich, I know that something is wrong: a) with the fish's health, b) with the fish's environment, or c) with the fish's diet. These are very broad conditions of course, which can be even further encapsulated in the broader term "STRESS". Any of the things mentioned above constitute stress, per my perception anyway.

Personally, I have never witnessed any of my own fish spontaneously contract ich. There was always something that triggered it, and I have been fortunate enough to be able to correct it every time (about four cases total). Here are a couple of my ich experiences.

I had two yellow coris wrasse for approximately six months. One somehow damaged his left fin quite badly, and it became infected. The next day, he also was affected by ich. The second yellow coris was never affected. I was able to get rid of the ich four days later, but the fish did perish as a result of the fin infection despite my efforts.

In this same tank about a month later, there was a power outage and the tank dropped nine degrees one night, to the low 70's. The next morning, all fish (a six-line and two neon gobies) had spots. I slowly corrected the temperature, fed heavily several times a day with garlic supplemented food, and all fish returned to normal by the second day (third for one of the gobies).

I battled my next case of ich by choice. While in a local store, I did something I knew better than to do and purchased a tiny sailfin tang that was covered with spots and lying on his side. He looked physically healthy, clear eyes and good color, other than an obvious case of malnutrition. I was heartbroken, and something told me I could nurse this little guy back to health. Well I did! Im ecstatic about it. I brought him home last sunday, started feeding a varied diet four times a day (formula 1/2, primereef, minced krill, brine shrimp) and made sure he had selcon-soaked nori and caulerpa available at all times. Getting him to eat the first day was tough, but he took to the nori quickly and then things got easier. By Wednesday, the third day I had him, he was clear of all ich and swimming quite happily. He's also got one hell of a gut!

So, while none of us may know what causes ich, I have my theories. Help the fish gain his resistance back and he will do the rest. This is all just my opinion, of course.

[Biosystems]

quote:

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Originally posted by Terry B:
Stress is a much more important factor for infection with oportunistic pathogens than with obligate ones. Falcutative pathogens usually only infect fish that are weakened in some way.

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Terry:

While I agree with your assessment that the disease state can not be caused without the presence of the pathogen (in this case crypto), stress is more likely a much more important factor for activation or exacerbation of infection of obligate pathogens including parasites and viruses. Obligate pathogens can also be quite oportunistic-taking full advantage of stressful situations and the responses or lack thereof that occur from this situation. Stressors are capable of producing a reduced ability of the immune system to respond to infection, as well as a decrease in the slime layer on fish, amongst other problems.
I myself work on an obligate pathogen of humans and the effects of stress have been well documented to produce the disease state. Not that crypto can remain latent in our system in the truest sense of latency, but it can without doubt be maintained at subclinical levels and maintained for quite some time evading our detection. If you consider that tomonts have been shown to remain viable (here defined as capable of releasing threonts) in systems in the absence of fish for greater than 2.5 months it would take only a subclinical episode 6 times a year to perpetually have parasite present in the system. We do tank cleanings and water changes more often than this and these tasks are in themselves stressful-making it possible for the potential of our fish to be more susceptable.

This is not to argue against you contention that this parasite can be eradicated and prevented. I believe it can and if it was a problem in nature or in food fish hatcheries in the US maybe cures would be more forthcoming for the aquarium industry. But the truth is, this is not an important pathogen-unless you ask me, or you, or any other aquarist that has had to combat the darn thing.

Thanks to your articles and efforts to introduce hyposalinity treatments to the average aquarist, people are now armed with an efficacious and safe method of treatment. I just hope that in the near future an invertebrate safe method of treatment will also be introduced so that we can treat the disease in our reef tanks.


My arguements are open for discussion.....


Tim

[LisaJill]

Well I'll quickly be 'in over my head' in this, but I thought I would share my experience...

I have not had a bout of ich since I set up my 45 gallon tank. This tank is a reef and it's been through a lot of changes - it's always been overstocked (according to popular opinion) Even when I had a pair of very aggressive maroon's in there I never managed to get Ich.

This is on top of the fact that I don't quarantine, and could not at this point even if a needed to. My LFS has UV's on all their fish tanks and this may help.
I only shop at one LFS.

But what interests me is that I HAVE brought home infested fish. Never badly infested - one or two spots and some scratching noticeable. These fish have always cleared up within 2 days in my tank and it has never 'caught on'.

The tank's been going a year now. I do not know if I'm just really lucky. I do know that even with the overstocking, and the maroon clowns, I have never had ongoingstress. Any aggression was quickly over with. Even thought the number of fish in my system was, is and always will be high, I always make it a point to add fish with different territorial and usually differnet food niches.

I have no stress in my system now due to the above (removign those damned maroons was the best thing I could have done )

i don't really know what the point of this is - according to most of what I've read, my approach to the numbers I can keep has always been dead wrong - yet it works.

I'm not a disease expert, or even an amateur. I've never had any reason to research Ich or any other disease. But because my experience seems to differ to everyone elses, I wanted to share it. Maybe because the Ich never caught on,and new fish always cleared, it is now not present in the tank regardless of the high number of hosts? Or maybe I'm really good at keeping fishies

I doubt I'll take much part in this. I've seen your other threads Terry and they're so in depth that they make me nervous.



Lisa

OH! If I may add - I live in Australia. All of my fish are of indo-pacific origin. Maybe the shorter shipping times, possibly (probably) collectors with better collectin practices etc have helped?

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www.lisa-jill.com

[Staceon]

How do you determine cryptocaryon irritans are obligate pathogens? Why do they have to have a fish as host?

[john f]

Cannot complete life cycle without a fish host.
This has been well known for years.

John

[Staceon]

I know that part, but WHY?

[jameso]

doh, double post

[This message has been edited by jameso (edited 09-22-2000).]

[jameso]

Hi Terry,

Of course stress does not cause Ich. That would be like saying stress causes the common cold, or even that stress causes AIDS. (Yes, this was actually a hotly debated subject in the 80's).

NOW, what we all know is that it is a heckofalot easier to get a cold (or even HIV infection) if you are immunosupressed, and as you have stated before, stress is a powerful immunosuppresant.

Now, as to the second question, yes, ICH organisms (in whatever stage) are pretty much always present in marine aquaria, be they home aquaria, collectors/holding facilities, or wholesalers tanks. I would hypothesize that if we tested 100 marine aquaria (from the groups listed above) and we tested 100% of the water, rocks, inverts, clams, fish, and sand in each system, that we would find ICH in 90% of them.

With that said...what to do about it? Well, if you are 90% sure that you have ICH in your system, but your animals don't show any outward signs of being bothered by it, then of course, don't worry. Shoot, this can go on for literally years. But, what happens when your heater sticks in the off position? Blamo! Your fish start to exibit ICH spots. Under the abovesaid conditions, the ich did not cause the "disease," the water temp drop did, wouldn't you agree?

So then, we could change your statement ("ICH organisms cause ICH Disease") to The ICH organisms are necessary, but not sufficient to cause the ICH disease. A combination of the presence of stress AND ich organisms causes ICH disease.

I hope that was clear.

James Wiseman www.reefs.org

[This message has been edited by jameso (edited 09-22-2000).]

[Steve Richardson]

It seems that it is a common opinion that stress causes Ich.

hmmm. I think your assumption is bad. I dont think anyone really believes that stress spontaneously creates Ich. Doesnt seem that way to me at all...

...but it only causes problems when the water quality is poor or the fish is weakened by something like a wound.

or.... (drumroll please....)

Stress?



-S

[Terry B]

Hi Doug,
Skipping quarantine is certainly the quickest way to introduce Ich into your tank. I wouldn’t say that it's been well researched yet, but there is some evidence that fish that have previously recovered from Cryptocaryonosis will have a limited immunity to reinfection. This means it is possible to have a low-level infection in your tank without seeing spots. When the new addition is added that does not have the same level of resistance there can be in outbreak. If you're established fish have built-up some resistance to an existing infection you may not see any obvious symptoms until something happens to upset to this precarious balance. Yes, you can be lucky and purchase fish that are not infected. However, this is a bit like playing Russian roulette, sooner or later you usually get burned. This is just one reason why practicing quarantine is highly advisable. I would not say that stress is an unimportant factor with Ich, but even the healthiest fish can become infected when the population level of parasites becomes too dense.
Terry B

[Terry B]

Aquaman
Don’t say that no one has ever argued that stress causes Ich. There are a couple people that have argued this continually. Yes, of course fish are more susceptible to infection when stressed. However stress is not necessarily required before fish become infected in an aquarium. There is not a dormant stage to ich apart from a host being present per-say. What is often confused as a dormant stage is when the parasite is in the tomont or reproductive stage off of the fish. Usually, the life-cycle lasts less than two weeks. Most people recommend that treatment lasts for three or four weeks. Leaving the tank fish-less for four to 6 weeks is long enough for the parasite to die out.
A virus cannot be compared in any way to an obligate parasite. They have little in common other than the fact that both are pathogens. A virus can live inside the body and remain dormant for some time. Ich is not a virus and does not behave as one. Again, I will repeat that stress is often a factor with ick, but in my opinion, stress is over emphasized. Fish can sometimes fight off a light infection. The fact remains that unstressed fish often become infected also.

[Terry B]

Lobster,
Healthy unstressed fish can become infected with Ich. Sometimes it's just a matter of the population level of parasites becoming so dense that the fish are overwhelmed. This explains why Ich usually appears on one or two fish before the entire tank becomes infected. The healthiest fish can have a perfectly high resistance, but it comes to a point where they can no longer fight it off by themselves.
Terry B

[Terry B]

Hi Biosystems,
I would disagree that stress is a more important factor with infections from obligate pathogens vs. facultative ones.
Here is a quote from G. A. Wedemeyer in the book “ to Fish stress and health in aquaculture.� “Of all the stressed mediated fish disease problems identified to date, those due to facultative bacterial pathogens are probably the most frequently encountered.� Facultative pathogens are only a problem when the fish are stressed, obligate pathogens can infect perfectly healthy specimens. I do agree that obligate pathogens can also be opportunistic. I am also aware that stress can certainly be immunosuppressive. As far as the slime layer goes, a temperature drop can reduce the mucous layer by as much as 50 percent.
You are also correct when saying tomonts can remain to system for couple months. However, the longer this period of time goes on, the less likely to theronts will be able to attach to a host. After a long period of time they can still hatch from the tomonts but the theronts are much less likely to succeed in infecting a host.
Thank you for your encouragement about helping to make hyposalinity well known to hobbyists. What do you think about garlic as a reef safe method of treatment?
Terry B

[lori344]

Tim & Terry,

I want to say the information you share is just wonderful. Thank you so much for your discussions on this board! I love it when you two post or hop into a thread. You two are so interesting and informative. I've learned much; I thank you, my reefs thank you, & my fish thank you! We are lucky to have you around!

~lori


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Like fine wine, reefs take patience & time

[This message has been edited by lori344 (edited 09-22-2000).]

[Terry B]

Staceon
Good question, obligate pathogens cannot obtain the nutrients required to survive and remain infectious when suspended in the water column or attached to sediment particles and require a living host in order to the grow and reproduce.
Terry B

[RobertK]

Hi Terry,
Long time no see. One of the things that struck me the most in my past readings on this topic was that the hormonal response to stress is remarkably similar in fish and other vertebrates, including humans. As you know, it has been well documented that various stressors in aquariums (aggression, overcrowding, poor water quality, sudden temperature change, etc.) lead to this hormonal response in fish, indeed a stressor is defined as a stimulus that leads to the release of stress hormones. As Biosystems has pointed out, it has been well documented in humans (and less well in fish) that stress hormones have a negative impact on the immune system, increasing one's susceptibility to infection if exposed to a pathogen or allowing a subclinical infection to worsen. In my experience, this has become accepted as common knowledge among many hobbyists (especially on this board), thanks in part to the efforts of people like you to dispel old myths.
Best regards,
Robert

[Terry B]

Jameso
I have to disagree on two points. First I do not believe at all that ich is pretty much always present in marine aquariums. This has been disproved with a sufficient amount of evidence. I can give you quote from the previously mentioned book to support this if you like. I also think you're percentage is way off. Secondly, Cryptocaryon irritans ARE sufficient to cause a disease outbreak. Perfectly healthy fish can become infected. Yes, stress can be an important factor in infection. However, stress is not necessarily vital for infection to occur. Yes of
Terry B

[Terry B]

Steve,
When you quoted me you should have looked at what I said a little closer.
"...but it only causes problems when the water quality is poor or the fish is weakened by something like a wound."
I was speaking about falcultative pathogens at that point not obligate ones.
Terry B to

[Biosystems]

TerryB:

It is interesting that you mention the temp drop decreasing the slime layer as many hobbyist have had crypto problems following temperature changes.

Have you noticed as well that crypto is a little known disease outside of the hobby? Often texts on marine parsitology completely do not cover the topic. I do not know if this is a case in A. Wedemeyer's book or not as I am not familiar with his/her writings. I do know from working in a dept. of veterinary micro and paras. for some years that parasites even in veterinary situations(where they are much more problematic) are often a forgotten issue. Often they are not referred to simply because there is not that many people that work on them.

For example in most texts they often refer to the most active part of a telost immune system is the antibody response (similar to what immunologist once thought for mammalian systems) yet in the case of fish the affinity of antibodies only increases 10 fold over continued exposure.....Leading me to believe that like mammalian systems other systems may be more active than previously thought. I only mention this, because I feel the feild is evolving and hopefully some time soon we will be able to introduce hobbyist to methods of treating if not preventing parasitic diseases.
As far as my thoughts on garlic-I ran a study that was described here some time ago on the use of garlic treatment for crypto infections. I do not know if it still exists but often times my results were misinterpreted. I do not think that garlic is a cure for crypto as this is not how ingestion of this product functions. It has been used for some time in the prevention of arthropods attachment in the vet. feild and it seems to perform the same task for fish. You know better than I do that often times people log on and write "My ich is cured" after only treating their fish the morning of.... You and I know that this is a normal course of the disease for the syptoms to subside in the evenings but often times they don't. There is no doubt in my mind that garlic was effective in my tests with P. hepatus-but it did not cure the disease per say. It did buy time for immune responses to counter the disease and take it to at least subclinical levels. I did however notice one or two spots in the specimens. This method was somewhat skewed as the control group was in an interconnected tank and this of course was a source of subsequent infection of the treated group. I wish I could have persued this and other tests forward if it were not for me torching my house.

\
Please keep up the conversation as it is only through these means that us as hobbyists will solve these problems.

BEst regards,
Tim