BSJF Necropsy (GRAPHIC)

Dentoid

Smile Maker
PREMIUM
That's the way Cory! Get back on the horse. You have made a great donation too the start of this cause. I for one am appreciative!:D
 

bluespotjawfish

Well-Known Member
:dryer: Had I been on top of this better, I could have donated many this past year.

:nono: I personally hope that I cannot contribute to further experiments!

I do think this is an interesting experiment and one that this species deserves. :hug1:

Can't wait to see the results of Frankie's icicle! I thought he had it framed by now! :yup:
 

kathywithbirds

Well-Known Member
Would getting other jawfishes other than blue spots help this?

(I DO NOT want to be able to help, my diamond goby is great so far!!!)
 

Dentoid

Smile Maker
PREMIUM
I don't know that other jawfish species are having this kind of poor survival in captivity. I know that Dusky jawfishes are pretty hardy and the Yellow headed and Pearly Headed jawfish are too. In fact they have been breed in captivity.
 

tbittner

Well-Known Member
All I can say is WOW!!! This is incredible! I can't tell you how impressed I am.

Now, as far as the blockage... Chickens eat grit to build up and keep built up a level of grinding material in their gizzard. That material is used to help grind the food up before entering the intestines for absorption. Obviously, a fish and a chicken aren't even close biologically speaking, but then again, what DO we know about the biological makeup of a BSJF. It would be interesting to see if the same blockage exists in other marine fish.

Incredibly impressive work, Scott! I wish I would have come over to help you with this.
 

Dentoid

Smile Maker
PREMIUM
Thanks Terry! If you ever need a necropsy done, bring the specimen over, I have the microscopes, instruments and beer! :drunk:
 

tbittner

Well-Known Member
Thanks Scott. Hopefully I won't have any specimens anytime soon though. :D

But I am really curious about the blockage though. I'm wondering if it serves a purpose or if it's truly blocking food from reaching the intestines and the poor fish starves.
 

Anselth

Well-Known Member
Terry, I'm inclined to think it's not a blockage that's killing the fish for a simple reason: The gut is empty. While a blockage in the intestine would certainly prevent the absorbtion of food, you should see undigested matter in the stomach, an overabundance of which would explain the lack of appetite. That doesn't seem to be the case here. I'm kicking around two possibilities in my head:

First, that the sand particles don't block the intestines, per se, but irritate them to the point that the fish does not want to eat. Similar to a human with a stomach bug. Unfortunately, the body is unable to pass the particle and the fish wastes away. I think this is unlikely, however, given that ingesting sand is probably something these animals do in the wild on a regular basis.

Second, a reaction between the stomach acids and the sand is either damaging the stomach lining and intestines, or irritating it to the point that the fish loses its appetite. The fish was apparently living in an aragonite sand bed in captivity. From the limited information I was able to find on the geology of the region, it seems like the sea floor in the Sea of Cortez would be mostly made up of silica and volcanic sands. Remember, aragonite is made of CaCO3, so a strong interaction with stomach acids is possible. The part of this theory that gives me pause is that the yellow-headed jawfish is a Caribbean species which we don't see this issue in. however, the Caribbean jawfishes may have evolved to deal with the interaction of acid and base in their stomachs.
 

thelastmucci

Active Member
I really don't have much input as far as what is killing these amazing creatures...I am however glad someone is taking a (semi *read cool*) approach to it all. I hope that you find the answers that your looking for whatever they may be.
 

30x30

Member
I wouldn't infer much about the lack of food in the fish because he was not eating for a very long time. During that time I was able to get him to evacuate once by doing a freshwater dip, to me this explains the lack of material further down the GI. I also know it was not taking any food in for a very long time.

I think the changes in DO2 thickened his GI mucus and trapped sand, this traveled down to a point where it eventually settled to create an obstruction. This fish remained interested in food for 7 or 8 days but the best he could do was swollow the Formula 1, and spit it back out 20 seconds later. I don't know anything about fish physiology, but I wonder if the sight of a meal, or the act of feeding should cause GI-motility, and the lack of this or impairment may have the ability to cause retrograde motility that caused him to spit things out. I do think the grain size was a secondary cause, perhaps larger grains would not be prone to entrapment. That's my final take, I documented a lot of this as it happened in a tread on the BS board.
 

vdituri

Well-Known Member
Karma to you Scott for taking the initiative on this!

Hopefully we can keep this going to further this study.

Are their digestive systems that much different than say a sand sifting goby (or even other species of jawfish) that a sand blockage in the intestine would be a bigger factor? Or possibly that since there are such a supply of gobies available when one dies we just go to the lfs and get a new one and they may be dying of the same problems with no one noticing?
 

thelastmucci

Active Member
I like this BSJF allot...but after reading all these horror stories about keeping them in captivity I think their best left in the ocean...if I want a goby that bad I"ll talk to becky..she's queen of the gobies...again job well done scott.
 

Dentoid

Smile Maker
PREMIUM
Terry, I'm inclined to think it's not a blockage that's killing the fish for a simple reason: The gut is empty. While a blockage in the intestine would certainly prevent the absorbtion of food, you should see undigested matter in the stomach, an overabundance of which would explain the lack of appetite. That doesn't seem to be the case here. I'm kicking around two possibilities in my head:

First, that the sand particles don't block the intestines, per se, but irritate them to the point that the fish does not want to eat. Similar to a human with a stomach bug. Unfortunately, the body is unable to pass the particle and the fish wastes away. I think this is unlikely, however, given that ingesting sand is probably something these animals do in the wild on a regular basis.

Second, a reaction between the stomach acids and the sand is either damaging the stomach lining and intestines, or irritating it to the point that the fish loses its appetite. The fish was apparently living in an aragonite sand bed in captivity. From the limited information I was able to find on the geology of the region, it seems like the sea floor in the Sea of Cortez would be mostly made up of silica and volcanic sands. Remember, aragonite is made of CaCO3, so a strong interaction with stomach acids is possible. The part of this theory that gives me pause is that the yellow-headed jawfish is a Caribbean species which we don't see this issue in. however, the Caribbean jawfishes may have evolved to deal with the interaction of acid and base in their stomachs.

Adam, in this case the stomach was full anterior to the blockage. This picture is of the stomach contents. The mass in the center of this picture are the stomach contents, mainly amorphous microscopically (mucus).

stomcont.jpg


The intestine posterior to the blockage was empty.

These are nevertheless thought provoking ideas.

Cory, interesting observations. We don't know what came first the mucus or the sand. I think the irritation by sand particles that Adam spoke of is a possibility. On the other hand perhaps something else caused the mucus and the sand was secondary as you suggest.

Victor, I believe that most fish have a similar digestive track anatomically and are relatively simple from a gross anatomic perspective. However, in herbivores their intestinal track is longer and more convoluted to accommodate a longer digestive period for the breakdown and absorption of plant material than carnivorous fishes. The BSJF has a short and straight intestinal track which is indicative of their zooplankton feeding preference.

Mucci, I understand your indifference, but there are reports of long term success with this species as long as their specialized husbandry needs are met. They are certainly not a species for the beginning aquarist. BTW, this is not a goby! Thanks for your input.
 

tbittner

Well-Known Member
That's an interesting question. Which came first, the mucus or the sand. The mucus could have certainly trapped the sand from leaving the body. But what could have caused the mucus build up? That possible worm?
 
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