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Well, I'd be interetested in anything someone can turn up on this, but one more question needs to be addressed:

When a fish cannot develop to its normal size due to stunting - intentional or otherwise, is the lifespan shortened?

If I take the same fish or two genetically similar fish from the same batch of fry and intentionally stunt one, then keep them both in pristine environments for the rest of their lives, does the stunted one see significant shortage of lifespan, in contrast to its sibling allowed to grow normally?

Bignose,

I think this is a fantastic post and I would also love to see proof on this. Not to say it doesn't occur, but IMHO a lot of what's said in the aquarium world are old wive's tales or marketing tactics to sell products. Very little of what's said is ever furthered by anything more then "my-friend-of-a-friend" statements.

Again, I believe stunting does occur and is detrimental to aquarium fish as most of us would agree, but to see actual proof would be very interesting.

Next time a customer at work brings in an exttremely deformed 12" oscar that spent the last 10 years of its life in a 30 gallon tank, I'll be sure to get a picture of it before we toss it in with the redtail cats.

Many people have brought in stunted fish, and this is a firsthand account from somebody who actually works at the LFS. It's truly a horrific sight to see, fish with twisted spines and lop-sided heads...

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I'm not your neighbor, you Bakersfield trash.

While I have no hard and fast proof like Cory Addict does, I take my proof from other cases.
Take a tree and bind a limb tightly, let it grow for a few years then remove the bindings. The tree will be deformed for life. Take a human and bind it's foot, the foot will be deformed for life. Take a human and put enough bands around the neck, soon the neck will be unable to support the head without the bands.

While some people might need to see proof I can understand from other examples that fish do stunt and that it's not a good idea to put them in a situation where they might become stunted.

^_^[hr width='40%']"I'm alright, I'm alright
It only hurts when I breathe"

The reason I ask is that bulging organs, to me, does not seem to be the way nature works. Stunted populations occur all the time in nature -- limitations on food or pollution in the native waters frequently result in populations that are smaller than norms. Predation can also be a common cause. Sport fishermen know this when the state wildlife and fishing commissions restrict fishing in a lake or stream in order to give the populations a chance to recover.

In fact, long-term stunting is the reason we have the dwarf varieties of some of our favorite fish: dwarf gouramies, dwarf cichlids, etc.

One must differentiate between environment-induced stunting and natural selection for smaller body sizes; "stunting" of game fish typically results from the tendency of fisherman to capture and cull larger, more impressive specimens of a given species, handing an advantage to smaller fish that might otherwise have difficulty openly competing for resources with their less diminutive kin - in turn, the mean adult size decreases. [In other instances, however, overpopulation may act similarly, hastening conspecific competition and once again favoring smaller organisms (having lesser metabolic demands)].

Last edited by Veneer at 18-Mar-2005 20:08

As far as I know, I think I was the first one, or one of the first, to bring this semi-factoid to the boards. Since then it has blossomed to unforeseen proportions; all from the mouth of a boy who people thought knew what he was talking about. Or maybe my memory is just fuzzy and I only THINK I was the first person to bring this to the forum. I guess I'm going crazy. Whatever.

Anyway, though stunting and the organs continuing to grow has some ground in truth, there have been some crazy turns with how people have expressed this. I've even seen once mentioned how the bones also contine growing and the skeleton eventually pierces through the fish. But I digress. However, I have seen for myself some of the effects of stunting.

Oscars I have seen often have bulginb eyeballs and hunched backs; stunted and distorted for sure, but those eyeballs are probably from bad water conditions rather than stunting. I have seen one real extreme example of stunting; it was of a Tiger Shovelnose. This Tiger Shovelnose seemed like a rather healthy fish except for one thing: the head was too big for it's little body. That's right. The head was disproportionately large. This implies that the body slowed down or even ceased growing.

BTW, what do you mean when you say stunting is responsible for giving us dwarf gourami and dwarf cichlids? Those are naturally found species of fish, unless of course you mean some sort of environmental or evolutionary issue. In any case, I'd like to know your source on that, as that's a pretty bold claim without proof on your own part.

Last edited by Shinigami at 10-Mar-2005 22:15

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The aquarist is one who must learn the ways of the biologist, the chemist, and the veterinarian.

Just because it is deformed doesnt mean it is because its organs grew too big for the fish.

Bone structure and organs are different.

When a women is pregnante, her bone structure changes (bones get more far apart, and their back bends more) but her organs arent bulging, and exploding in her body.

Also, when a stunted fish dies, shouldnt it literally be all exploded looking, and bulgy?

I am interested in finding real, first-person, actual experience proof of the oft-repeated warning about stunted fish. Specifically, the advice and warning that many, many people give that stunting a fish "causes its organs to keep growing, while its body stops growing, resulting in a deformed fish from the bulged organs.

I am not arguing that stunting does not exist, and I agree that it can have some dire consquences on the health of the fish. The lifespan and health of a fish kept in a too small tank is seriously comprimised. However, the bulging organs theory is repeated a lot, but I have never seen proof.

I do not want, friend-of-a-friend-had-a-stunted fish sotries, I do not want, well so-and-so on the Internet/chat board/webpage said so, I do not want LFS employee/owner/customer said so.

I do want proof that the organs keep growing, and this will probably require some brave soul to perform an autopsy. Not just some brave soul, but a knowledgeable scientist who will know what the normal fish organs are meant to be, and that the bulges from a case of stunting are not tumors or infections or other diseases that the fish will be more e to b/c of the stunting. I want real proof that stunting, and only stunting, has caused bulging organs.

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The reason I ask is that bulging organs, to me, does not seem to be the way nature works. Stunted populations occur all the time in nature -- limitations on food or pollution in the native waters frequently result in populations that are smaller than norms. Predation can also be a common cause. Sport fishermen know this when the state wildlife and fishing commissions restrict fishing in a lake or stream in order to give the populations a chance to recover.

In fact, long-term stunting is the reason we have the dwarf varieties of some of our favorite fish: dwarf gouramies, dwarf cichlids, etc.

Finally, from "Development and aging of the liver and pancreas in the domestic carp, Cyprinus carpio: From embryogenesis to 15-year-old fish" by Fishelson L and Becker K in ENVIRONMENTAL BIOLOGY OF FISHES Vol 61 Issume (1) pages 85-97, 2001,

In 15-year-old experimentally stunted fish (110-120 mm TL) the liver and pancreas resemble those of juvenile fish appearing much healthier than those of 8-10 year old large carp from commercial ponds.

Sure, those are only a few organs and a general assumption about all the organs cannot be completely made completlely accurately, but the liver is a fairly sensiitve organ since it does a lot of the housekeeping of the fish's immune system.

Here is another from "Effect of stunting of juvenile bighead carp Aristichthys nobilis (Richardson) on compensatory growth and reproduction" by Santiago CB, Gonzal AC, Aralar EV, Arcilla RP in AQUACULTURE RESEARCH Vol 35 Issue (9) pages 836-841, JUL 23 2004:

The carp stunted for 6, 12 and 18 months showed growth compensation, although their weights and lengths were slightly lower than those of the control fish. The body weight and length of fish stunted for 24 months were the lowest throughout the rearing period. Sexual maturation occurred only in the control fish and those stunted for 6 and 12 months. However, the onset of gonad maturity was delayed significantly (P<0.05) in males stunted for 12 months and in both groups of stunted female fish.

Stunting delayed the development of the fish, but no mention of bulging organs or other deformities.
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So, I suppose I have dropped the gauntlet for anyone who has proof. I am not arguing to go ahead and stunt a fish in a small tank, but I do not think that overstating the effects and using effectively scare tactics of telling people that "your fish's organs will explode!" is fair, either. I have a very open mind, and would like to see some proof for the other side of the argument. At this point, I can really only find hearsay and rumor.

Thanks

I will admit to doing this.

I bought 2 yabbies, Cherax destructor.

One was kept in a 2 gallon tank, one was kept in a 33 gallon tank, both unheated, both fed earthworms every few days, and the odd pellets and flakes.

The 2 gal yabbie stunted rather severely. There was no physical deformities other than the fact he was small.

The 33 gal yabbie grew to be full size.


The yabbie in the 2 gal outlived the yabbie in the 30 gal by about 6 months. They were about 6 years old.


Now i'd bet that fish would handle this situation slightly differently, but its interesting none the less.

I have some platies in my 33 that i moved from my 26. In the 26, tey had room to move, but probably got less food than the adult platies. now they are in the 33, they are STILL tiny.


Obviously the period for that type of growth hjad passed, and now they are stuck, because they didn't get enough nutrients at that crucial time.


I don't actually have a point here.

I have never seen organs grow too large unless there was an illness involved.

I HAVE seen spinal deformities and gill problems, but its entirely possible they could have been affected by ammonia and nitrite uptake, as if you are housing a fish in a tiny tank, that is probably going to be an issue.

For animals, the entire universe has been neatly divided into things to (a) mate with, (b) eat, (c) run away from, and (d) rocks. - Terry Pratchett

Working link:

http://img.photobucket.com/albums/v398/Kleevage/stunt.jpg

Your link doesn't work, noodles. :#( Maybe it's just photobucket having issues again today.

Stunting has no genetic basis; this being the case, "stunted genes" (which in reality, do not exist) are not passed on to prodgeny. In relation to evolutionary induced resizing, Veneer has got all the mechanics of the process down cold.

I do not believe that organs grow out of proportion relative to the fish. I find myself agreeing with the topic creator in that they will stop enlarging at a certain point. Growth factors in cells will inhibit growth as cell density reaches a maximum. However, premature inhibition results in deformities in organ structure, as certain areas of the fish continue to grow to suit functionality. The same is true for the skeletal system. Bones, by all technical and mechanical definitions, can be considered as "organs", and they stunt is a similar fashion.

There are certain regions neccesitating growth with increased age and size, those being the spinal cord and all nervous related structures (which is why stunted fish are often seen with huge, deformed heads and bent spines).

While the advice may be "plain wrong" (I am, admittedly, often wrong), it is not to say that one should keep fish in smaller tanks.


EDIT: Forgot--you want firsthand experience.
[link=http:// img.photobucket.com/albums/v398/Kleevage/stunt.jpg ]http:// img.photobucket.com/albums/v398/Kleevage/stunt.jpg [/link]

I bought this angel labelled as a naja gold veil, after much discussion with heaven (thanks for clearing this up), it was discovered that these were not only not najas, but they had been severly stunted by previous aquarists. He lived for 5 more years with a sibling, and they spawned several times. Eventually, he was sold with a great deal of the rest of my fish on account of having to relocate.




Last edited by Cup_of_Lifenoodles at 17-Mar-2005 01:19

To a small degree this has gotten away from my main and foremost question. Specifically, is there any real evidence that stunting causes the skeleton to stop growing, but the organs do continue to grow?

I was using all the other references and theories as contrary evidence... that is, several studies have been undertaken about stunting in nature, but no mention of overgrown bluging organs. The theory about long-term malnutrition and the smaller fish having a greater chance to reproduce is just that, a theory. It is no more than possible further evidence that stunting in nature can and does occur, but I have never seen a report or article that mentions overgrown organs.

Again, the oft-repeated advice to members on this and many other Internet message boards is that stunting of your fish causes their organs to overgrow and bulge. Mainly, I feel that nature does not work that way, but would change my mind if someone can show me evidence of these larger organs caused only by stunting alone. To date, no evidence yet, so I feel that this advice is just plain wrong.

i agree with the above from acidrain

cooler temps slow metabolism and therefore less nutrients r taking in thus slowing growth

in canada a prime example of this is in wild pickeral

lake erie which has a warmer body of water n a longer summer season walley grow rather large n quick as do salmon
but jsut a 15 hour drive north walley n salsom grow much slower n stay much smaller
an erie lake walley at 2 years should weigh bout 2-3lbs n b bout 24" long where as more northern fish wood b 5-6years of age to reach the same size
colder water is to blame

and for most fish if the temp drops where done gradually over time the fish can n will adapt for the most part
after all piranhas r now survivng canadian winters

"Those are naturally found species of fish, unless of course you mean some sort of environmental or evolutionary issue. In any case, I'd like to know your source on that, as that's a pretty bold claim without proof on your own part."

I certinaly do not have proof as this is more of an evolutionary issue. However, I have seen it theorized that the dwarf varities have come about because of stunting if you consider a food/nutrient shortage. If every fish recieves an equal proportion (no tank bullies), a smaller fish may develop quicker, since its smaller body does not require as many nutrients. It develops faster, mates sooner, and its genes get passed on. However, this kind of stunting only occurs over several, several generations, with undoubtedly several, several premature deaths becuase of emaciation of the larger malnurished members of the population.

I am lost here, as you say you don't have proof as this is more of an evolutionary issue, but your statement is of an evolutionary/environmental issue. What you have described is in no way stunting. It is a definition that states the better equipped fish are the survivors. And thus an adaptation/evolutionary statement. Through adaptation and evolution, the strongest/more well equipped/adaptable living organisms will be the survivors. The dwarf fish from the wild, have evolutionarily adapted to their environment. Not been stunted, but have adapted and evolved to live in their environment.

If your statement were true about stunting, then it could be said/interpreted that all fish, less only the largest sharks and such, are all stunted fish. And not just what we have named as dwarfs. In other words, the whale shark is the only truly correct sized, unstunted fish. Any fish smaller than the whale shark, is a stunted fish.

Take a tree and bind a limb tightly, let it grow for a few years then remove the bindings. The tree will be deformed for life. Take a human and bind it's foot, the foot will be deformed for life. Take a human and put enough bands around the neck, soon the neck will be unable to support the head without the bands.

Many of you, are mixing up deformity and stunting. As is common knowledge, fish continue to grow till they die. Even stunted fish continue to grow, no matter what size their tank is, until they die. Crooked spines, bulging organs, bent fins, and others, are more deformities from the situation than what can be considered stunting. Any deformity fish can develop from a situation, are just that, deformities, not stunting. For this reason, is why I rarely post in any threads of this nature. As they are not the same thing. But it is an on going debate. That many people have a strong passion about. To truely stunt a fishes growth, the fish must retain its development in a normal and natural way. Just in at slower rate. As well as a smaller complete size. Placing a fish in a smaller tank is not a way to stunt a size out come of a fish. But a way to make the fish grow deformed.

Finally, from "Development and aging of the liver and pancreas in the domestic carp, Cyprinus carpio: From embryogenesis to 15-year-old fish" by Fishelson L and Becker K in ENVIRONMENTAL BIOLOGY OF FISHES Vol 61 Issume (1) pages 85-97, 2001,

"In 15-year-old experimentally stunted fish (110-120 mm TL) the liver and pancreas resemble those of juvenile fish appearing much healthier than those of 8-10 year old large carp from commercial ponds. "

Sure, those are only a few organs and a general assumption about all the organs cannot be completely made completlely accurately, but the liver is a fairly sensiitve organ since it does a lot of the housekeeping of the fish's immune system.

Here is another from "Effect of stunting of juvenile bighead carp Aristichthys nobilis (Richardson) on compensatory growth and reproduction" by Santiago CB, Gonzal AC, Aralar EV, Arcilla RP in AQUACULTURE RESEARCH Vol 35 Issue (9) pages 836-841, JUL 23 2004:

"The carp stunted for 6, 12 and 18 months showed growth compensation, although their weights and lengths were slightly lower than those of the control fish. The body weight and length of fish stunted for 24 months were the lowest throughout the rearing period. Sexual maturation occurred only in the control fish and those stunted for 6 and 12 months. However, the onset of gonad maturity was delayed significantly (P<0.05) in males stunted for 12 months and in both groups of stunted female fish. "

Stunting delayed the development of the fish, but no mention of bulging organs or other deformities.

This is a true statement/development outcome about stunting. The fish size, including organs, has been stunted. Their development of organs and maturity, has been slowed. But, there is no mention of deformities.

Finally, from "Ecology and adaptation of stunted growth in fish" by J. YLIKARJULA, M. HEINO and U. DIECKMANN, in Evolutionary Ecology, volume 13, pages 433-453, 1999.

"Alleviation of stunting has been observed in a population of roach (Burrough and Kennedy, 1979). There, high parasite-induced mortalities had increased the growth rate of fishes so that normal-sized individuals could emerge after years of stunted growth. Likewise, average lengths-at-age increased significantly in a previously stunted white fish population following a period of
intensive fishing in Northern Norway (Amundsen, 1988). In South-East Norway, biomass removal of perch has led to increased growth rates (Linlùkken and Seeland, 1996). However, assessing the consequences of such biomass removal is not unambiguous since other fish species were removed simultaneously. Moreover, it cannot be excluded that the observed increase in growth rates has resulted from an improvement of water quality."

In short, some evidence shows that a fish once removed from the conditions that stunt it, can indeed grow normally once again.

Yes, many do return to normal growth. But I disagree with your statement here. Again, here you are quoting statements that have to do with evolution and environmental situations. There are not deformity issues. And you state "…can grow normally once again." What is "normally" in your statement? As the fish are considered growing "normally" in the environment they are in. We altered the environment in the above quote, that showed the fish grew larger. Is this statement saying that if we take fish out of their natural "dangerous" environment and place them in pristine conditions, and they grow larger, faster, healthier, that they are stunted in their natural environment? There are many fish that grow larger in the aquarium than they will in their own natural environment. This is a proven statement and fact. As well as many other animals, and critters will live longer healthier lives in the captive contained environment, than in their natural environment.


True stunting, stunts the entire fish, including the organs, fins, and total grown length. But, the fish is in all ways, identical to the larger "normal" sized fish in every way. The best way to stunt a fish, is to raise it in colder temperatures. This can be a tricky objective to perform. I have done it with several different cichlids. My original objective, was to get some cichlids to spawn in colder temperatures, and not stunt them. The stunting was a side effect though. All of these fish lived/are living healthy lives, of the same time frame of their larger relatives. Now, not all the fish I have done this with, have become stunted in size, and have actually grown to the same size as their cousins. But many have only grown to sizes half that of their genetic family tree. And, they are spawning in these colder waters, and the fry are growing in them as well. The fish I have used in my experiments are cichlids from the rift lakes of Africa, as well as several West African varieties. I currently have several Malawian Cichlids, that are normally occur and spawn in temps of 76-82F, living and spawning in temps of 65-69F. Some have stunted, and others have not. Those that have stunted, when moved to warmer temps, have not grown at all, even after up to 2 years.

My original study was to determine/prove two things; 1) that many fish from warm temp environments, can endure lower temps, rather temporarily or permanently. 2) and they can live healthily and breed at these temps as well.


_____________________________________________________________

There is always a bigger fish...

that UNLESS the customer admits that their 12inch oscar was in a 30 gallon

They do say that, since they don't know that they are doing anything wrong. They simply want new fish because usually "the kids thought it was too ugly now". It's not entirely the customer's fault, because most of them were not informed how large the oscars would get (stupid chain stores). The fish brought in usually have, in addition to the deformities, calluses or blisters on their lips that I can only assume are from rubbing against the sides of the tank, and nearly always they have severe HITH.

We get in tons of large oscars at the store (usually five or more per month), and I don't quite think it is a coincidence that the fish brought in from small tanks cared for by uninformed aquarists are extremely unhealthy, while the ones that come from large tanks (100+ gallons) are healthy, robust, and seeming always in the mood to spawn.




Last edited by Cory Addict at 12-Mar-2005 01:19

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I'm not your neighbor, you Bakersfield trash.

It's truly a horrific sight to see, fish with twisted spines and lop-sided heads...

I find one issue with this statement.

What is to stay that the twisted spine, lopsided head and whatever else could have been caused by disease, or a genetic deformality?

There are alot of diseased or deformaties that may not present themselves until the fish is larger. Or especially from a head problem may have been caused by an injury, or illness (hole in the head a prime example - I've seen horror stories of a oscar with HITH that was in a rather pristine environment, but still recover and still have a rather deformed head).

The problem with seeing fish come into stores (and I've seen my fair share also), that UNLESS the customer admits that their 12inch oscar was in a 30 gallon or whatever for an extended period of time, or you saw first hand that the fish was in this situation, before the fish was surrendered to the store, it is hard to say what caused deformalities.

Heck, I've got deformed fish, I've spawned plenty of fish also - and I personally do not cull any deformed fish, i let them die naturally.

i've got a deformed danio - but its in a 20 gallon tank - I don't think the spinal deformity was from cramped conditions.

Oscars I have seen often have bulginb eyeballs and hunched backs; stunted and distorted for sure, but those eyeballs are probably from bad water conditions rather than stunting.

This is the kind of issue I am curious about. The Oscar in a too small tank is a very common example.

Many people have brought in stunted fish, and this is a firsthand account from somebody who actually works at the LFS. It's truly a horrific sight to see, fish with twisted spines and lop-sided heads... (Cory Addict)

It is tough to discriminate the organs versus the skeletal deformations -- that is, organs versus spines. This is why I feel this can only be answered following an autopsy by a trained scientist who would know the size and proportions of the organs of a given fish. That is, yes, the fish is stunted and smaller, but are all the organs still in proportion to the size of the fish? I have no doubt that the results are dramatic, but from what I gather from above, we should be warning people about deforming their fish's skeltons, not about the never-quit-growing organs.

In addition to the cramped quarters, I would place very good money that an owner that does not care enough about their fish to purchase a large enough tank, also does not do the necessary water changes, filter maintenence, etc. Meaning it increases the difficulty of isolating the stunting causes and effects. For example, fish is kept in too small tank, becomes stressed, immune responces are weakened, and its body is unable to fight off a viral infection that causes swelling. Or pop-eye, or neon-tetra disease or TB, or other such problem. Each of these diseases' effects include deformation in one form or another.

To truly study the question I have posed, a population of fish would need to be kept in a series of tanks of different sizes, but with as many other parmeters the same, as much as possible. However, an autopsy by a qualified person may yield a fair amount of insight without performing a large set of (admittedly rather cruel) experiments.

Let me say this again just to be perfectly clear: I would like to see proof of the continuing-to-grow organs theory. I am not looking for proof of what stunting can do, I know the cruelty and suffering a stunted fish can suffer. I am just looking for proof of this particualar theory that has run amok (in my opinion) on the Internet.

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Those are naturally found species of fish, unless of course you mean some sort of environmental or evolutionary issue. In any case, I'd like to know your source on that, as that's a pretty bold claim without proof on your own part.

I certinaly do not have proof as this is more of an evolutionary issue. However, I have seen it theorized that the dwarf varities have come about because of stunting if you consider a food/nutrient shortage. If every fish recieves an equal proportion (no tank bullies), a smaller fish may develop quicker, since its smaller body does not require as many nutrients. It develops faster, mates sooner, and its genes get passed on. However, this kind of stunting only occurs over several, several generations, with undoubtedly several, several premature deaths becuase of emaciation of the larger malnurished members of the population.

--------

Finally, from "Ecology and adaptation of stunted growth in fish" by J. YLIKARJULA, M. HEINO and U. DIECKMANN, in Evolutionary Ecology, volume 13, pages 433-453, 1999.

Alleviation of stunting has been observed in a population of roach (Burrough and Kennedy, 1979). There, high parasite-induced mortalities had increased the growth rate of fishes so that normal-sized individuals could emerge after years of stunted growth. Likewise, average lengths-at-age increased significantly in a previously stunted white fish population following a period of
intensive fishing in Northern Norway (Amundsen, 1988). In South-East Norway, biomass removal of perch has led to increased growth rates (Linlùkken and Seeland, 1996). However, assessing the consequences of such biomass removal is not unambiguous since other fish species were removed simultaneously. Moreover, it cannot be excluded that the observed increase in growth rates has resulted from an improvement of water quality.

In short, some evidence shows that a fish once removed from the conditions that stunt it, can indeed grow normally once again.

Last edited by Bignose at 12-Mar-2005 00:10

im not arguing for or against stunting yes i think it does exist n yes i think it can lead to death but not by exploding
even if the organs did continue to grow the fish wood most likely die before it exploded
fish have stress levels much lower then humans
if a human drinks to much alcohol there liver will increase n become inflamed to a point, this largeing of the liver most likely wont kill the person but causes alot of stress n pain
this isnt due to stunting i no, but what is there to say that even slight grow of organs cant kill a fish as there bodies r designed for balance n agility within water
and we all know once that is disrubted the chance for survival is greatly deminished

i have recieved stunted fish before,4 red by reds a year n half old that were jsut over 1.5" long, when i placed them in an appropriate tank they did grow. they r now, after 8 months in my care, up to 4" n r now breeding as of jsut last night
so fish can continue to grow after stunting.
the red by reds when i got them jsut looked like mini reds as there was no sign of deformation

The pregnate woman was not a good example.

"When a women is pregnante, her bone structure changes (bones get more far apart, and their back bends more) but her organs arent bulging, and exploding in her body."

What happens is the growing fetus and uterus expands and pushes her internal organs out of place, or presses down on other organs. But this is a natural process, and not one forced upon the woman by crowded living quaters.