"Essay" on Drop Eye (from a physician/biologist)

[Mr.Nooby]

All Aros can get DE, it is just a matter of time. Koji's silvers might not have DE now, but it still can develop.

No one has really ever though about Stress as a factor. My 10''Silver arowana in a 125, begun devoloping DE, when my dad added koi to my tank. it was obvious it was stressed out. it would swim irratically, He would bump into the side of walls, but he i don't think he ever jump through the lid. I use egg crates, so they should break alot easier then glass lids.


Also other things we should consider is living space.

Silvers are by far the most common and the cheapest. So most aquarist will have Silvers living in smaller tanks which can lead to poor water quality.

Jardini are common too, but since they are more aggressive they would have to be kept alone, and that would lead to less bio load.

We dont see too many Blacks or asains with DE, but they are a lot rarer in the trade.
Also since they fetch a higher price. Most blacks have competent owners. in addition, Asians are gonna get the best of everything because their owners can afford it.

Bad water quality and small living conditions would cause stress. Stress may lead to DE.



I wanna support the trauma theory also, When i was moving the same Silver arowana, with slight drop eye. IT jumped out of the bag and flopped on the floor. When i was able to put him in the tank. the DE got a lot worst, like mild DE.


I think the fatty substance that develop behind the eye is equivalent to callus skin for humans. Callus develop because of irritation/pressure. People who use their hands a lot (construction workers), will have a lot of callus on their hands. The callus protect their hands and skin from ripping and bleeding.


I am currently growing a community of silvers (5) and two jars. The Silvers are from the same suppliers, and the jars are from TFD fish. IF they are wild, the would most likely be caught in the same location; but they could be farm bred (i got them in Dec, at 4''). Either way they would be coming from the same gene pool.


Im gonna test the genetic theory. if one of them get DE, the other will too, because they would share the same gene pool. Environment would not be factor because they are living in the same tank. Would factor that we cant test will be the trauma.

if any of the aros get DE, then it could/would destroy the theory of weak/lazy eye muscles. My aros are always aware of their surroundings because they can be attacked by any other aro. so if they do get DE, i dont think this would be a possible factor for causing de.

Well even tho they are from the same pool that dose not mean that if one gets it the other one will. traits are different for each individual arow even tho they are from the same gene pool.

 

[Mr.Nooby]

The one problem I have with the OP's idea that they get DE from looking down is that he is basically restating Lamarck's theory of evolution (ie-giraffes have long necks because they keep stretching them to reach high leaves), which has long been accepted as disproven in the scientific community. If this was true, then all the offspring of an aro with DE would have DE. I honestly have no idea what causes DE, but I don't believe it to be always looking down. I would think either head trauma or diet is the most likely cause.

i don't think so. that is more of environmental factor. to pass on it has to be the genetic that determines it.

 

[sbuse]

http://www.monsterfishkeepers.com/forums/showthread.php?t=297873&highlight=socket&page=4
post #38

Lets go over your points comparing to the case mentioned in post #38
To summarize what happened in that case, 2 aros gets DE over a long weekend (3 or 4 days i assume).

Generally, this is one of the most detailed cases you're going to find on this forum. Going by the given information, the following of your theories are already crossed out:
1. Small tank
2. Fat/callus development
3. Genetics
Why these two won't work? Obivous; becuase 3 or 4 days is definitely not enough time to allow for the eyes to drop due to these factors.

Improbable Theories:
1. Bad water
A 3 or 4 day break without feeding is definitely not going to ruin your water. The average water change schedule is even longer than that. Highly improbable that the eyes dropped due to bad water quality.

So whats left? The most probable one is still head trauma. A long weekend without any human interaction, with all lights off. The only possible factor left is that the aro jumped, hard. Theres alot more points on the post itself that I don't really want to type out again. So, yea... Lets try and make this one of the few GOOD, open DE threads...

i don't think that this takes out the genetics theory...i mean how the genetics would play a part in de would be to make them more suseptible to getting it from head trama...witch would explaine why blacks and jars don't get it as much even with repetive jumps...it wouldn't be that hard to test the dna of all aro sp. find the common traits in aros that don't get de, and the common traits of aros that do...just try to find a difference in the ones that get it vs the ones that don't...then find the same trait that the aros one the same "side" have but the others don't...

 

[Bderick67]

i don't think that this takes out the genetics theory...i mean how the genetics would play a part in de would be to make them more suseptible to getting it from head trama...witch would explaine why blacks and jars don't get it as much even with repetive jumps...it wouldn't be that hard to test the dna of all aro sp. find the common traits in aros that don't get de, and the common traits of aros that do...just try to find a difference in the ones that get it vs the ones that don't...then find the same trait that the aros one the same "side" have but the others don't...

When talking genetics it should only be considered with in the species. Better then 95% of large silvers posted on the net have DE. This does not matter whether wild caught or captive bread. So to state that genetics would be cause for a silver getting DE would be like stating genetics is the reason silver aros are silver.

If a conclusion could be drawn as to inbreeding being a cause then genetics could be considered as an argument

 

[Gshock]

i don't think that this takes out the genetics theory...i mean how the genetics would play a part in de would be to make them more suseptible to getting it from head trama...witch would explaine why blacks and jars don't get it as much even with repetive jumps...it wouldn't be that hard to test the dna of all aro sp. find the common traits in aros that don't get de, and the common traits of aros that do...just try to find a difference in the ones that get it vs the ones that don't...then find the same trait that the aros one the same "side" have but the others don't...

Forgot about this theory. In genetics, I was thinking about genetics causing the eyes to eventually drop with age. Unfortunately, nobody is going to spend this much money to go through with testing, research and samples just so we hobbyist can find out a difinitive answer to DE and to see if theres any possible way of prevention. Nothing more can benefit from doing testing on this.

 

[Bennobius]

i support this theory, the friend from who i got my Arowana from used to only keep a very thin substrate on the bottom of his tanks and his arowanas spent lot of time watching their reflections on the bottom of the tank and most of them developed DE

 

[Bderick67]

i support this theory, the friend from who i got my Arowana from used to only keep a very thin substrate on the bottom of his tanks and his arowanas spent lot of time watching their reflections on the bottom of the tank and most of them developed DE

That reflection is only an illusion and does not exist from within the tank. Just like the reflection you see on both side panels and even the top water line as seen in the pic below.

 

[sbuse]

When talking genetics it should only be considered with in the species. Better then 95% of large silvers posted on the net have DE. This does not matter whether wild caught or captive bread. So to state that genetics would be cause for a silver getting DE would be like stating genetics is the reason silver aros are silver.

If a conclusion could be drawn as to inbreeding being a cause then genetics could be considered as an argument

i might have worded it worng, but i was tring to state the genetics could be a contributor rather then a cause on its own...as for the sp. only, yes and no...yes to do some tests and no cause for them to be clasified as arowanas the should have some genetic trat simmilarities...i haven't seen any dna matirial for aros, but the body structure of all of them exept the african seem to point to the possibility that they all could have evolved from a basic arowana, just took on extra traites to suit the diff. eco systems the inhabit...

Forgot about this theory. In genetics, I was thinking about genetics causing the eyes to eventually drop with age. Unfortunately, nobody is going to spend this much money to go through with testing, research and samples just so we hobbyist can find out a difinitive answer to DE and to see if theres any possible way of prevention. Nothing more can benefit from doing testing on this.

the op was mentioning something about having access to all or most of the stuff needed...yes it would be costly, but more could come out of it the just the de...we have plenty of past evidence of what defects inbreeding can have...more so with mammal inbreeding the fish, but no one realy "cares" about fish...i mean if a herd of deer dies do to a infection that due to inbreeding they are all suseptible to every one freaks out and prevenitive measures are taken...if a pond of fish die for the same reason it gos unnoticed...

 

[Gshock]

the op was mentioning something about having access to all or most of the stuff needed...yes it would be costly, but more could come out of it the just the de...we have plenty of past evidence of what defects inbreeding can have...more so with mammal inbreeding the fish, but no one realy "cares" about fish...i mean if a herd of deer dies do to a infection that due to inbreeding they are all suseptible to every one freaks out and prevenitive measures are taken...if a pond of fish die for the same reason it gos unnoticed...

Once again, lets be realistic. We're going to need a ton more than just a couple tests to even have people acknowledge that we found the root of the problem. We're talking hundreds of different samples. This is not going to happen without some kind of big agency backing. Second of all, like you said, nobody (other than us hobbyist) even cares about fish such as arowana. Why would scientist put money into this if theres tons of other problems relating to fish which support human life?

 

[sbuse]

Once again, lets be realistic. We're going to need a ton more than just a couple tests to even have people acknowledge that we found the root of the problem. We're talking hundreds of different samples. This is not going to happen without some kind of big agency backing. Second of all, like you said, nobody (other than us hobbyist) even cares about fish such as arowana. Why would scientist put money into this if theres tons of other problems relating to fish which support human life?

true, i geuss i was more or less getting at "the ball doesn't start rolling by itself"...i know it problibly would not happen with out an agency...angain if there is no testing done we would never know, just have a **** ton of theorys...witch is right were we started...