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Hello, please tell me how you humanely dispatch your tilapia for the table.  When I googled it, some said using ice chokes them, others say shock them (?) others say drive a pin through their skull, or hit them in the head with a hammer.  Wow, I can't picture myself chasing flopping fish with a hammer!  I just want to do the job without causing the fish too much pain.  I also think when something is being killed, it can put out body chemicals (kind of like we have coritsol) because of fear.

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Is there anywhere that shows how that works?  Are the fish still in the tank?



Cecil Dale Baird said:

Carbon Dioxide, regulator, air line, and a diffuser would be the most humane in my opinion. Puts them permanently to sleep.

Thank you drumurphy, for your thoughts and ideas.  I was hoping ice would be the most painless way, since it's fairly easy to set up.  However, I'm willing to go to more work if it would be less trauma on the fish.  When you only have a few fish, you sort of get to know and like them over time.  I feed mine fresh sweet potato leaves still on the vine for a treat every day, and they come up and eat them out of my hands.  I should not have gone there.

Anyways, I appreciate the detailed explanation you went into, including the salt etc, so I do it right the first time.

drumurphy said:

I would highly recommend ice water - really any large container filled with about 85% ice and 15% water plus a fair amount of salt - 

When their body temp drops below 60F degrees or so, tilapia are pretty much immobilized – they shut down very fast (although I am sure nobody can look into their experience to assure us of the speed or “painlessness” of it all) - and under about 50F they are gone - the salt helps drop the temperature of the water below freezing as it lowers the melting point of ice and draws energy out of the liquid water – it also helps dispatch bacteria on the outer surface and gills (the fish will gulp water for about 15 seconds or so). Killing is killing, but this is fast and there is very little violence, thrashing, blood etc – if that’s a measure of “humanely”, then I suppose it’s the best way I’ve found. In our country now-a-days I suppose there would be a market for tilapia drones – kill them from far away without the icky part. Very  American.

Anyway, I recommend ice water. I would suppose it’s easier on us than it is on the fish – any way you approach it. We harvest 100 to 150 fish at a time, and I always have a few moments of introspection when the work is done. Oddly enough for me, cleaning them is easier than killing them. Another observation – the first 10 are always harder to dispatch than the last 50 – something else which I suppose is very human … creepy, but human. Explains a bunch of things we do to each other –IMHO.

Killing your animal food is not necessarily a pleasant activity, but it is eminently REAL, and ultimately very healthy in a psychological human way - an honest act. And something we evolved/were designed (pick your poison) to do. I was a vegetarian for 20 years based on the idea that if I wasn’t willing to kill something, I hadn’t earned the right to consume it. Or alternatively, I realized I unconsciously viewed myself as so above such a thing that I wouldn’t do it personally, but yet I could expect to pay someone else to do my dirty work. A pretty ugly way to walk through life, sad to say, and possibly a source of many of our current problems. Also, I saw a slaughterhouse operation first hand at an impressionable age. I would recommend “A Mothers Tale” by James Agee for an alternative view of our modern food supply chain. Anyway, all that was a long long time ago, and I’m no longer a vegetarian – or I guess better put, I’m an occasional but unrepentant omnivore. But I have gone as far as assisting at least once in dispatching and processing anything I’m now willing to eat myself – I have farmers in the family, so I’ve been afforded opportunities the average city dweller might not have.

So, in a word (or two) - Ice water.

These fish are the last animal left to keep me from being vegetarian.  We'll see how it goes.



Sunny Oettel said:

Thank you drumurphy, for your thoughts and ideas.  I was hoping ice would be the most painless way, since it's fairly easy to set up.  However, I'm willing to go to more work if it would be less trauma on the fish.  When you only have a few fish, you sort of get to know and like them over time.  I feed mine fresh sweet potato leaves still on the vine for a treat every day, and they come up and eat them out of my hands.  I should not have gone there.

Anyways, I appreciate the detailed explanation you went into, including the salt etc, so I do it right the first time.

drumurphy said:

I would highly recommend ice water - really any large container filled with about 85% ice and 15% water plus a fair amount of salt - 

When their body temp drops below 60F degrees or so, tilapia are pretty much immobilized – they shut down very fast (although I am sure nobody can look into their experience to assure us of the speed or “painlessness” of it all) - and under about 50F they are gone - the salt helps drop the temperature of the water below freezing as it lowers the melting point of ice and draws energy out of the liquid water – it also helps dispatch bacteria on the outer surface and gills (the fish will gulp water for about 15 seconds or so). Killing is killing, but this is fast and there is very little violence, thrashing, blood etc – if that’s a measure of “humanely”, then I suppose it’s the best way I’ve found. In our country now-a-days I suppose there would be a market for tilapia drones – kill them from far away without the icky part. Very  American.

Anyway, I recommend ice water. I would suppose it’s easier on us than it is on the fish – any way you approach it. We harvest 100 to 150 fish at a time, and I always have a few moments of introspection when the work is done. Oddly enough for me, cleaning them is easier than killing them. Another observation – the first 10 are always harder to dispatch than the last 50 – something else which I suppose is very human … creepy, but human. Explains a bunch of things we do to each other –IMHO.

Killing your animal food is not necessarily a pleasant activity, but it is eminently REAL, and ultimately very healthy in a psychological human way - an honest act. And something we evolved/were designed (pick your poison) to do. I was a vegetarian for 20 years based on the idea that if I wasn’t willing to kill something, I hadn’t earned the right to consume it. Or alternatively, I realized I unconsciously viewed myself as so above such a thing that I wouldn’t do it personally, but yet I could expect to pay someone else to do my dirty work. A pretty ugly way to walk through life, sad to say, and possibly a source of many of our current problems. Also, I saw a slaughterhouse operation first hand at an impressionable age. I would recommend “A Mothers Tale” by James Agee for an alternative view of our modern food supply chain. Anyway, all that was a long long time ago, and I’m no longer a vegetarian – or I guess better put, I’m an occasional but unrepentant omnivore. But I have gone as far as assisting at least once in dispatching and processing anything I’m now willing to eat myself – I have farmers in the family, so I’ve been afforded opportunities the average city dweller might not have.

So, in a word (or two) - Ice water.

Wow, David, that paper was VERY informative!  I really like the way they compared all the different anesthetics-and it looks like the Clove oil is the least invasive--it says it causes NO distress.  So, would that mean, we could use Clove Essential Oil (EO), to stun anesthetize the fish, then put them in ice water (so they are not shocked) to finish the job? HOWEVER, hmmm, if we do plan to eat the fish, does anyone know any Cloved Tilapia recipes?? In other words, I wonder if it would make the fish taste like cloves? 

Alex Veidel said:

Lol, no, I didn't catch that one either :) I figured it was something like that.


David - WI said:

All I did was click "Link" in the upper left-hand corner and fill in the text and the url.  In the editor, it shows as an underlined, blue hyperlink... but when it posts it shows just plain text.  I can show you - look above!

I suppose you missed the Aqui-S link in the next post, too?   Click Me!

(I agree that it doesn't look like a link, but the time for me to be able to edit my post had long passed by the time I actually saw my own post 2 hours later.)


Thank you all for your help, after reading the paper David sends us  a link to (on Aqui-S Clove EO), I think I'm understanding more what to do.  On the paper, one can learn much as to how each of the different harvesting methods affect the animal and its meat.  It is quite scientific, with pictures and test results that show acidity and chemicals caused by stress to the animal.  Here is a small excerpt:  

RESTED HARVESTING

Rested harvesting is the practice of conserving intra-cellular energy reserves during harvesting and suppressing the release of stress-related hormones and chemicals, resulting in improved product quality and consistency.

Most fish demonstrate a maximal emergency response when threatened in any way. This may follow a sudden disturbance from a net, a noise or other unexpected activity, or when they are removed from the water. The response usually involves a change in the heart rate; increased production of cortisol, adrenaline and noradrenaline; and vigorous muscle contractions. The increased exertion exhausts the normal aerobic energy resources of the muscle forcing the muscle to rely on anaerobic glycolysis for the production of ATP. An associated build-up of lactic acid results along with a reduction in muscle pH and an overall reduction in muscle energy reserves (Lowe et al. (1993)). 

It goes on to say that the meat turns acidic (pH can actually be tested) from the trauma, and that Clove Oil calms them before the harvest.  (However, as a distributor of Essential Oils, I know that many EOs are laced with chemicals, and that one would want to use Clove Oil that was Certified Pure, Organic (like doTerra Essential Oils).  The website on Aqui-S goes on to explain how to add the Clove Oil to the fish water, then proceed with the harvest of the calmed fish.  Sounds good.  Funny thing is, I knew Clove Oil was used for many years by dentists as a topical anesthetic, but never knew it had a systemic, calming effect on fish!   



Sunny Oettel said:

Thank you all for your help, after reading the paper David sends us  a link to (on Aqui-S Clove EO), I think I'm understanding more what to do.  On the paper, one can learn much as to how each of the different harvesting methods affect the animal and its meat.  It is quite scientific, with pictures and test results that show acidity and chemicals caused by stress to the animal.  Here is a small excerpt:  

RESTED HARVESTING

Rested harvesting is the practice of conserving intra-cellular energy reserves during harvesting and suppressing the release of stress-related hormones and chemicals, resulting in improved product quality and consistency.

Most fish demonstrate a maximal emergency response when threatened in any way. This may follow a sudden disturbance from a net, a noise or other unexpected activity, or when they are removed from the water. The response usually involves a change in the heart rate; increased production of cortisol, adrenaline and noradrenaline; and vigorous muscle contractions. The increased exertion exhausts the normal aerobic energy resources of the muscle forcing the muscle to rely on anaerobic glycolysis for the production of ATP. An associated build-up of lactic acid results along with a reduction in muscle pH and an overall reduction in muscle energy reserves (Lowe et al. (1993)). 

It goes on to say that the meat turns acidic (pH can actually be tested) from the trauma, and that Clove Oil calms them before the harvest.  (However, as a distributor of Essential Oils, I know that many EOs are laced with chemicals, and that one would want to use Clove Oil that was Certified Pure, Organic (like doTerra Essential Oils).  The website on Aqui-S goes on to explain how to add the Clove Oil to the fish water, then proceed with the harvest of the calmed fish.  Sounds good.  Funny thing is, I knew Clove Oil was used for many years by dentists as a topical anesthetic, but never knew it had a systemic, calming effect on fish!   

That's a trend that's becoming more and more popular, not eating meat until you've "earned the right", and it's one that I like. It adds a lot more depth to the whole vegetarian thing. Personally, I like to call myself a "vegetable-arian", a man who eats and enjoys meat on occasion, but just really likes produce. And yeah, I've killed a few things myself. Personally, I didn't find it difficult emotionally, but it is a lot of work. One of the reasons I decided to cut back :) Not to mention that American's are eating way more meat and dairy products then is even healthy.

drumurphy said:


Killing your animal food is not necessarily a pleasant activity, but it is eminently REAL, and ultimately very healthy in a psychological human way - an honest act. And something we evolved/were designed (pick your poison) to do. I was a vegetarian for 20 years based on the idea that if I wasn’t willing to kill something, I hadn’t earned the right to consume it. Or alternatively, I realized I unconsciously viewed myself as so above such a thing that I wouldn’t do it personally, but yet I could expect to pay someone else to do my dirty work. A pretty ugly way to walk through life, sad to say, and possibly a source of many of our current problems. Also, I saw a slaughterhouse operation first hand at an impressionable age. I would recommend “A Mothers Tale” by James Agee for an alternative view of our modern food supply chain. Anyway, all that was a long long time ago, and I’m no longer a vegetarian – or I guess better put, I’m an occasional but unrepentant omnivore. But I have gone as far as assisting at least once in dispatching and processing anything I’m now willing to eat myself – I have farmers in the family, so I’ve been afforded opportunities the average city dweller might not have.

So, in a word (or two) - Ice water.

The following other methods are known to be used: carbon dioxide (CO2) in holding water; chilling with
ice and CO2 in holding water; salt or ammonia baths; asphyxiation by removal from water;
exsanguination without stunning. However, they have been shown to result in poor fish welfare.

http://www.aphis.usda.gov/import_export/animals/oie/downloads/aahc_...

You mean "poor fish welfare" as in "death"?

David - WI said:

The following other methods are known to be used: carbon dioxide (CO2) in holding water; chilling with
ice and CO2 in holding water; salt or ammonia baths; asphyxiation by removal from water;
exsanguination without stunning. However, they have been shown to result in poor fish welfare.

http://www.aphis.usda.gov/import_export/animals/oie/downloads/aahc_...

You're talking about a pretty small amount of clove oil that's put into the water for only about 10 -15 minutes prior to harvesting the fish; I don't think there's any way that even a "detectable" amount of clove will make it into the meat/flesh of the fish.

I think a big consideration is that in order to reduce the stress and stress reactions in the fish; the water that you put them in to anesthetize them should have the same temperature, pH, DO level, etc as the water they just came out of... or better yet capture and move them to a smaller tank 4 or 5 days before you plan to harvest them so all the "stress" chemicals from handling them have dissipated, then quietly sedate them and so you can harvest them without any additional stress.

Sunny Oettel said:

HOWEVER, hmmm, if we do plan to eat the fish, does anyone know any Cloved Tilapia recipes?? In other words, I wonder if it would make the fish taste like cloves? 

No, I think they're talking about the welfare of the fish up to the time of death... and we were talking about changes to the flavor/texture/quality of the fillets caused by stress reactions in the fish.

More info about "fish welfare": http://www.humanesociety.org/assets/pdfs/farm/hsus-the-welfare-of-f...

Personally, I don't know how many wild fish die of "old age"... a majority of them are probably eaten alive by a bigger fish, a bear, or an eagle; so I'm not sure they are actually any worse off being slaughtered at a fish farm; but the quality of the final product is a big concern for me.


Alex Veidel said:

You mean "poor fish welfare" as in "death"?

David - WI said:

The following other methods are known to be used: carbon dioxide (CO2) in holding water; chilling with
ice and CO2 in holding water; salt or ammonia baths; asphyxiation by removal from water;
exsanguination without stunning. However, they have been shown to result in poor fish welfare.

http://www.aphis.usda.gov/import_export/animals/oie/downloads/aahc_...

I think the quote David gave about "poor fish welfare" is their way of saying the fish appeared to suffer.

Alex Veidel said:

You mean "poor fish welfare" as in "death"?

David - WI said:

The following other methods are known to be used: carbon dioxide (CO2) in holding water; chilling with
ice and CO2 in holding water; salt or ammonia baths; asphyxiation by removal from water;
exsanguination without stunning. However, they have been shown to result in poor fish welfare.

http://www.aphis.usda.gov/import_export/animals/oie/downloads/aahc_...

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