Stingray Dissection *Warning Graphic Images

[JK47]

Excellent write up Dieselhybrid this is now a sticky. Sorry for your loss but thank you for turning that into a contribution for your fellow fish keepers. Two thumbs up

 

[Dieselhybrid]

ANTX-a (Anatoxin-a) can be removed via ozone filtration and/or reverse osmosis. See citation below. I was not able to easily locate a full text, but I imagine that if you ask the corresponding author very nicely, they'll send you a copy of the paper, and might even give you some practical advice. Keep in mind that if you are having ANTX-a problems in your local waterbody, you're probably having cyano-toxin problems in general; there are likely other cyano-toxin present in your water at relevant concentrations.

Granulated activated carbon may also remove ANTX-a, but how exactly this works (i.e. the most effective porosity and whether biodegradation occurs after adsorption) is an active area of research at this time.

If the water authority is allowing you to drink the water, it's likely safe for your fish. ANTX-a is an acetylcholine mimic; both humans and rays have acetylcholine receptors. Given that the cyanobacterial species associated with environmental contamination with ANTX-a have a world-wide distribution, it's likely that rays have encountered this compound at some point in their evolutionary history, and therefore possess adaptations to deal with background levels of contamination. That is, I wouldn't stress out about it if you have "some" ANTX-a in your tanks. With the amount of money you have locked up in rays and the water authority testing on a weekly basis while you are doing water changes 2x/week, I think it would be prudent to install a RO or ozone pre-filter.

This is unlikely to have caused they death of your ray by itself given that you have not reported ill-effects in your other fish, but this is certainly a source of that amorphous and cumulative thing we call "stress".

++++++++++++

Removal of the cyanotoxin anatoxin-a by drinking water treatment processes: a review
By:Vlad, S (Vlad, Silvia)[ 1 ] ; Anderson, WB (Anderson, William B.)[ 1 ] ; Peldszus, S (Peldszus, Sigrid)[ 1 ] ; Huck, PM (Huck, Peter M.)[ 1 ]

JOURNAL OF WATER AND HEALTH

Volume: 12

Issue: 4

Pages: 601-617

DOI: 10.2166/wh.2014.018

Published: 2014

View Journal Information

Abstract
Anatoxin-a (ANTX-a) is a potent alkaloid neurotoxin, produced by several species of cyanobacteria and detected throughout the world. The presence of cyanotoxins, including ANTX-a, in drinking water sources is a potential risk to public health. This article presents a thorough examination of the cumulative body of research on the use of drinking water treatment technologies for extracellular ANTX-a removal, focusing on providing an analysis of the specific operating parameters required for effective treatment and on compiling a series of best-practice recommendations for owners and operators of systems impacted by this cyanotoxin. Of the oxidants used in drinking water treatment, chlorine-based processes (chlorine, chloramines and chlorine dioxide) have been shown to be ineffective for ANTX-a treatment, while ozone, advanced oxidation processes and permanganate can be successful. High-pressure membrane filtration (nanofiltration and reverse osmosis) is likely effective, while adsorption and biofiltration may be effective but further investigation into the implementation of these processes is necessary. Given the lack of full-scale verification, a multiple-barrier approach is recommended, employing a combination of chemical and non-chemical processes.

Author Information
Reprint Address: Vlad, S (reprint author)

Univ Waterloo, Dept Civil & Environm Engn, 200 Univ Ave W, Waterloo, ON N2L 3G1, Canada.
Addresses:

[ 1 ] Univ Waterloo, Dept Civil & Environm Engn, Waterloo, ON N2L 3G1, Canada
E-mail Addresses:svlad@uwaterloo.ca

Thank you for all of this info Grinch . Our water has tested back within the acceptable range so I have the drips back up in running from the lake. The water goes through a sediment filtration and UV but that's all before the tap. I should have mentioned this but I have a large RO system that feeds into 2 55gallon barrels daisy chained together with a float switch, still up from my saltwater days. Comes in useful so I never took it down. It's fantastic to learn that this is effective at treatment, as I'll admit I did use some blended in when I've been short on water the last few weeks.

I must say I have been fishing off of the dock and I have caught the usual trout and pikeminnows and they are healthy despite the high levels (I haven't eaten the trout despite the temptation). Perhaps rays could be more sensitive but all of the natives are fine in the lake, no dieoffs reported. A local resident knows someone at a local University who tested for the spectrum of blue/green toxins and said only anatoxin-a was present. We are forming a committee to educate residents that the fertilizers are causing eutrophication of the lake and if we don't reduce this could be an annual problem. The thought has crossed my mind to buy the property across the lake and drilling a well as a contingency plan. But all things considered I don't think this was the cause of death but definitely an area of future concern. Something to be aware of.

Thanks for your help pal

 

[Grinch]

"High levels" is in reference to human risk. From what I've seen, that number is 1ug/L. <1ug/L is acceptable, above that is not. I've not seen any solid rationale for 1ug/L other than that it is a convenient number. Happy to help

It seems like you have the resources to drill a well... that seems like it might be best WRT your rays.

 

[Dieselhybrid]

Outstanding journal necropsy! I'm sorry that the conditions allowing such an investigation requires such a loss.
I agree with Grinch in that the egg-bound condition may have led to a sepsis condition. Ovoviviparous species tend to absorb eggs that are past their usefulness. A chemical change or calcification of the ovum could have prevented the conditions needed for reabsorption by the female. I once saw a crude test where a suspected calcified egg was freeze dried then subjected to a hydrochloric acid wash. A reaction from the calcifications proved that the egg had been infused with calcium preventing the body from reabsorbing the egg as nutrients back to the body. The massive protein bolus of the egg's nutrients became a battlefield of bacteria leading to sepsis of the reproductive organs and blood poisoning of the specimen.

In preserving the pattern of the specimen, I'd recommend the Japanese art called; Gyutaku or fish-printing.
View attachment 1257258
There are 'how-to' videos on the procedures and many books available on this ancient art form.
View attachment 1257259
In using this art form, transfer defects can be filled in and blended. Also, colors can be matched to what the living specimen displayed. The traditional backings can be readily sealed against fading and olfactory by-products better than a wet, slimy towel can.

To further the investigative possibilities of future necropsies, I highly recommend incorporating a dissection microscope into the study. Simple slide-prep procedures are available on-line from numerous sites. Checking blood and viscera for bacteria/fungi/protozoans/etc. may yield blaring answers for the reason of a sudden-death loss. Dissection microscopes are easily found in places like eBay for much better prices than those at university or medical supply outlets. (pic is just one example. There are many brands and configurations available. Many have digital cameras allowing computer storage of microscope captures for later study and manipulation by software).
View attachment 1257263

Finally, off the top of my head, for expensive specimens as this ray, I recommend consulting your local vet in the procedure to draw and preserve blood samples for sending off to the proper lab for a basic battery of testing. Your vet may be willing to provide the drawing materials, standard and anti-coagulant blood tubes, and anything else he feels may assist in the necropsy. More involved testing may include blood culturing for bacteria and fungi but, those may be cost prohibitive.

Thank you for the inspiration Oddball! I've learned a great deal from this forum and you specifically over the years. We appreciate your support. I agree with both you and Grinch that the reproductive system looked problematic with the large size and number of eggs. I believe you are right and she had a difficult time reabsorbing them or that abnormality led to the loss of life.

The Japanese fish printing looks exactly like what I had in mind. I will certainly look into that. Once again you save the day. This type of resourcefulness is what I was talking about with Oddball, folks. Thanks again.

I am prepared to invest in a microscope, I have a decent budget. Is that model the one you would recommend? Or a good enough model? Mind sending me a PM sir?

I have a good friend whose spouse is a Veterinarian. I don't think she specializes in fish but I'm sure I can build through her network. I'm encouraged through the difficulty of the loss. I'm pleased that it has turned into something positive for everyone to build on.

 

[Dieselhybrid]

"High levels" is in reference to human risk. From what I've seen, that number is 1ug/L. <1ug/L is acceptable, above that is not. I've not seen any solid rationale for 1ug/L other than that it is a convenient number. Happy to help

It seems like you have the resources to drill a well... that seems like it might be best WRT your rays.

Thanks again Grinch, realizing I had a typo in my last message. I meant property across the lake road, not across the lake haha

 

[Grinch]

Thank you for the inspiration Oddball! I've learned a great deal from this forum and you specifically over the years. We appreciate your support. I agree with both you and Grinch that the reproductive system looked problematic with the large size and number of eggs. I believe you are right and she had a difficult time reabsorbing them or that abnormality led to the loss of life.

The Japanese fish printing looks exactly like what I had in mind. I will certainly look into that. Once again you save the day. This type of resourcefulness is what I was talking about with Oddball folks. Thanks again.

I am prepared to invest in a microscope, I have a decent budget. Is that model the one you would recommend? Or a good enough model? Mind sending me a PM sir?

I have a good friend whose spouse is a Veterinarian. I don't think she specializes in fish but I'm sure I can build through her network. I'm encouraged through the difficulty of the loss. I'm pleased that it has turned into something positive for everyone to build on.

Oddball suggested a 3D (stereoscopic) dissection scope. A better choice would be a compound scope, given your budget (or lack there-of?). With an oil-immersion objective you will be able to visualize bacterial cells directly. Look into gram-staining. With a compound scope and gram staining you can make some strong conclusions WRT whether sepsis is/was an issue.

 

[Dieselhybrid]

Excellent write up Dieselhybrid this is now a sticky. Sorry for your loss but thank you for turning that into a contribution for your fellow fish keepers. Two thumbs up

JK47 I appreciate your condolences Justin. You and the forum and are welcome and a big thank you to everyone here. This place has saved the lives of countless fish and helped promote the hobby.

Your 600 build series has been a great resource for me. I'll be plumbing a unique system soon, I hope you don't mind if I send you a message or two if I need some advice in the future?

 

[Oddball]

For proper examinations, I'd recommend both a dissection microscope for viewing aspects of the specimen during the coarse necropsy. A microscope on a swing boom would allow for detailed examinations during the main examination.



As Grinch pointed out, a compound microscope would be ideal in IDing possible microorganisms within the specimens tissues and fluids.



I assumed that a ray breeder could justify the costs of the scopes with the sale of one or two pups.

 

[Cichlidae]

As a veterinarian I have some recommendations. Organs need to be opened and inspected to found abnormalities. There are changes that are visible in the tissues depending on the cause of damage, like the color. Sometimes biopsies are necessary to know what really happened with the tissue and I don't think there is a Pathologist who works with stingray tissues. I would go with a systemic damage or poisoning.

The eggs have everything that a new life needs to become a complete creature. They're used to raise viruses in laboratories. There is a possibility that the eggs became growth media for bacteria.

It's really sad that we need to lose this beautiful animals to understand them better. She was incredibly beautiful.

 

[Dieselhybrid]

For proper examinations, I'd recommend both a dissection microscope for viewing aspects of the specimen during the coarse necropsy. A microscope on a swing boom would allow for detailed examinations during the main examination.

View attachment 1257374

As Grinch pointed out, a compound microscope would be ideal in IDing possible microorganisms within the specimens tissues and fluids.

View attachment 1257375

I assumed that a ray breeder could justify the costs of the scopes with the sale of one or two pups.

Perfect Oddball thank you. I'll order some equipment on the advice