Mystery Wrasse has locked jaws

injektion

New member
I was feeding my mystery wrasse this morning and all of a sudden it couldn't close its mouth! it's not completely open, as i've seen it open much bigger while stealing krill that i feed my anemone, and it still eats by sucking up food into its mouth. it isn't struggling to breath or anything but should i be concerned? will this go away or is it gonna be stuck like this forever?
 
my yellow wrasse didthis a couple times when fighting with one of my othet fish. seemed stress induced but it went away.
sorry but i have no tips for ya.....hope your fish gets better.
 
You said the magic word: KRILL

A steady diet of krill, esp. FD krill has been linked to lockjaw in many predatory species, so I'd change up what you're feeding the fish and start giving it a nice, varied diet.

I suppose the 'nem may have zapped the fish too, which may have temporaily paralyzed its mouth, but it sounds like lockjaw to me. Sometimes the fish's mouth "resets", sometimes it requires intervention, but once a fish has gotten lockjaw, they seem more prone to it recurring in many cases.

HTH
 
Do you have a link to any studies linking the two together?

As Steve mentioned, this is nothing new. However, I'll ask Renee is she has any papers/references that refer to the phenomenon, as she's the piscine nutrition/health geek in the house.

It has to do with nutritional deficiencies in a diet high in krill.
 
oh i don't feed it krill, and certainly not as a staple diet. it's just that when i had an anemone it used to steal the krill from its tentacles, probably once a week or so. the anemone is long gone (probably half a year or so now) so i don't think the locked jaw has anything to do with either of those things.

as i said earlier, it happened right when i was feeding the tank a bunch of defrosted hikari food; spirulina brine shrimp, mysis, mega marine, etc. he usually goes right next to my pipette to wait for the food and yesterday when it tried to take a bit of some brine shrimp his jaw got locked.

jaws are still locked today but still eating the same amount it usually does so not in panic mode yet lol
 
I've seen this happen maybe 4 or 5 times - never to any fish that was being fed FD krill, but certainly it happens when they are eating - the cases I saw were all hyperextension of a small bit of bone at the top, perpindicular to the maxillary - likely the fish extends it too far and it sticks. There may well be something about size or texture of FD krill that leads to a propensity for this, but I don't think that it is nutritionally, it is a physical lock in the cases I've seen.

Since the fish is still feeding, I'd leave it be. I've tried manipulating the bone back into place with two fish, it worked for one and only partially worked for the other one. The first fish did it again, and I left it alone and it got better on its own, and never happned again.


Bill
 
There may well be something about size or texture of FD krill that leads to a propensity for this, but I don't think that it is nutritionally, it is a physical lock in the cases I've seen.

The problem I have with this thinking is that lionfish that are fed diets of krill frequently get lockjaw, and in larger species/specimens, no krill is large enough for size/texture to really matter IMHO. I've also seen lions dislocate their jaws by bashing their mouths on rockwork when chasing live fish. In those cases, their jaws popped back into place after a couple of days.

How's the fish doing now, injektion?
 
it's doing alright, no better or worse. he eats everything still, albeit not as aggressively as it did before. i remember i had a green chromis that had this issue as well, where it just one day locked its jaws while eating but it went away after a few days so i didn't think to much of it.
 
Re: a diet connection to this. IDK - that certainly wouldn't apply to cases where the problem arose and then goes away on its own, or through manipulation of the bone.

I don't know of anything special about krill that would make it nutrionally defficient EXCEPT that it is very prone to oxidation during storage, and maybe the artifacts of that are causing a problem?

I first heard about the "krill issue" from a person who is a bit prone to over-extrapolation and is very focused on nutritional causes of problems (sometimes blind to other possibilities). She is very personable, and her hypothesis' gain wide acceptance, but I would still want to consider other possible reasons - such as the mechanical cause that I subscribe to.

Just wondering outloud - Perhaps it is a combination of diet and mechanical - where the bone clicks out of place due to some weakening of the skeleton? If so, then it is due to some deffeciency that is not unique to krill, because fish not fed krill have this problem as well. Maybe krill is just a good representative of a food that produces this deffeciency?

In any event, to somply say that "krill causes lockjaw" is not an accurate statement, and could cause people to shy away from an otherwise decent food - to even less appropriate options like brine shrimp.


Bill
 
Yes, it does happen in some fish, regardless of diet, but folks who aren't nutritionally deficient dislocate bones for other reasons. We keep Scorpaeniformes pretty much exclusively these days, and there are so many other great foods out there, and with whatever the added risk of krill may be, coupled with the fact that we've spent a lot of time and effort searching for some of these fish, why tempt fate?

It could indeed be oxidation, which could come from age, or the food being frozen-thawed-refrozen (it happens more often than folks think) but the freeze-dried stuff is a terrible food, period.

I'll have to ask Renee if she has any references in her journals and whatnot when she gets back into town.
 
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