Concluding Remarks
Important: Whatever you do, do one or more dry runs without the animal first. Practice the procedures until you are comfortable performing them without mishap before doing anything involving your pet.
Since 2003, when this site when up, I have had numerous reports of success and only one report of failure from someone who had no idea what might have gone wrong and who apparently was unable to understand the instructions provided. The lesson would seem to be: know your limitations.
Some non-believers in science question the need for experimentation, but I am quite sure that the procedures detailed above could not have been developed without some experimentation, by others and myself, and that to guess without testing would have been grossly irresponsible. Accordingly I wish to acknowledge the invaluable contributions of eight wild house mice, uninvited and destructive guests, who would otherwise have met their end in a mousetrap (sorry but allowing mice around our house in the country attracts way too many rattlesnakes, and I have a family to consider). Fortunately all I had to do was to verify that my methods, based on the research of others, were producing the same results as reported by real scientists who did all the real work. When I could put a wild, stress-out mouse to sleep without any apparent added distress, I ended my experiments. (Some mice, not partially confined by shredded paper and with room to wander, acted drunk, and staggered about for about 20 seconds before becoming unconscious—not a pretty sight, but they appeared more confused and disoriented than in pain).
Dry ice is used by some labs for CO2 euthanasia. Dry ice is a potentially hazardous substance. It is obtainable, but not readily available, and may not be obtainable at all when actually needed. The rate of sublimation in air is too slow, and adding dry ice to water results in violent, possibly explosive, boiling. It is difficult to control the rate of flow. Cold burns to you or your pet are a real hazard. Dry ice is not something you want to fool with at home.
While all vets should know how to perform humane euthanasia properly, some may not want to bother. If possible, do go to a vet, but make sure you observe the procedure, and if the vet doesn't want you to observe, go elsewhere. The preferred method (with small mammals) is to induce anesthesia using an inhalant such as Halothane or Isoflurane, followed by lethal injection or overdose of the inhalant. Some vets, when not being observed, may skip the first step and just inject something lethal into the body cavity.
At-home use of inhalant anesthesia is advocated by some as the best method of do-it-yourself euthanasia. Halothane, Isoflurane, Methoxyflurane, and other inhalant anesthetics are controlled substances obtainable (so far as I know) only by licensed veterinarians or researchers and are not legally available to the public. Some are being abused by a few recreational drug users, so it might be possible to obtain them, but even if you could, they are not appropriate for home use. First, with the exception of Methoxyflurane which is no longer available in the USA, inhalant anesthetics can only be used properly with an anesthesia machine capable of delivering them at the proper concentration (5% initially), and rate. Second, for your safety, you would also need a gas scavenger to protect yourself from fumes. Inhalant anesthesia is not a practical method for most pet owners.
Some claim that CO2 euthanasia is inhumane and should never be considered. This is based on the mistaken belief that CO2 acts only by inducing asphyxiation. Using it is likened to smothering your pet to death with a pillow; however it is a well established fact that carbon dioxide is a rapid depressant and powerful anesthetic. My observation is that CO2 acts as quickly and with even less excitation than Isoflurane (yes I tried it, given to me by a country vet who doesn't think I'm crazy and who has better things to do than euthanize small animals), perhaps because it is nearly odorless. At high concentration CO2 does indeed kill the animal by hypoxia, but only after induction of anesthesia. Even within the scientific literature you can find some misinformation. Procedures often call for precharging the euthanasia chamber with concentrated CO2 because this will cause the most rapid death. This is true, but speed is not the most important consideration. It is now realized that high concentrations of CO2 are noxious and inflict pain before induction of anesthesia. A gradual increase in concentration avoids this.
Some vets are concerned that CO2 euthanasia is ineffective in causing death and that some additional procedure is required to be sure death has occurred. This is an odd concern, at least with rodents, because respiration during the anesthesia phase is quite obvious as is the cessation of all respiration shortly after the high concentration CO2 is introduced. Neither mice nor men can stop breathing for 10 minutes and then revive (except in cases of hypothermia or animals that have evolved extraordinary breath holding abilities). If you have any concerns, wait 30 minutes or longer. The AVMA doesn't seem to have this concern.
I have received requests for a method that would be suitable for larger pets. Chicken producers are offering 'humanely slaughtered' chickens using CO2 which means it appears to work, even though chickens exceed the 2 lb. limit. I have recently become aware of the helium/nitrogen bag method of euthanasia advocated by right to die groups like Final Exit. This method of at home euthanasia for humans works by asphyxiation, but reportedly without causing distress. Helium is readily available for filling party balloons, and so this would be a practical method, but one I have not tried. Some oxygen may now be added to retail helium to avoid "misuse" so purity may be questionable.
I am glad to have this highly effective and practical method of at-home euthanasia, and hope others will make good and responsible use of it should the unfortunate need arise. Finally, I would like to thank all of those who have written to me to express their appreciation for the information in this paper, and for letting me know that much pointless suffering has been prevented. An unexpected result has been that much human suffering as may be caused by watching helplessly as a beloved pet dies has been reduced as well.
References
1. Report of the AVMA Panel on Euthanasia, JAVMA, Vol. 218, No.5, March 1, 2001
2. Hackbarth H, Kppers N, Bohnet W. Euthanasia of rats with carbon dioxide--animal welfare aspects. Lab Anim 2000;34:91-96
3. Leake CD, Waters RM. The anesthetic properties of carbon dioxide. Curr Res Anesthesiol Analg 1929;8:17-19
4. Niel L, Stewart SA, Weary DM. Effect of flow rate on aversion to gradual-fill carbon dioxide exposure in rats. Appl Anim Behav Sci 2008. 109:77–84.
http://www.journals.elsevierhealth.com/periodicals/applan/article/S0168-1591(07)00062-7/abstract
5. Niels Lombolt, M.D. THE USE OF CARBON DIOXIDE ANAESTHESIA BEFORE SLAUGHTER, Assistant Professor, Dpt. of Pharmacology, University of Copenhagen http://www.butina.eu/fileadmin/user_upload/images/articles/cabon_dioxide.pdf
External Links
- Animal Euthanasia Wikipedia article.
- Special-Needs Pets Article with general information.
- AVMA Brochure.pdf Info from the American Veterinary Medical Association.
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Comments
My concern is that if any of the adherents to this oh so righteous league were to fall off their high horse, they would scream for hours before hitting the real world, whereupon death would be certain. Speaking of the real world, some people do consider at home euthanasia, some attempt it, some consider the information this site offers first, and they and their pet have a better outcome. The opposition, again, offers only one argument, namely don't do it at home, always go to a vet (arguing that CO2 is wholly bad/unthinkable is secondary). Cassis, a vet and apparent point-person for the group, agrees, and that should come as no shock. Cassis offered four supporting references with a link to only the first which is by authors whose purpose in life is to end all animal experimentation (see below). As I have no wish to limit information or controversy, I added links to the other articles Cassis cited and added one to the site references above. For those wanting vastly more, try Google Scholar.
To boil down the research done over the past ten years, scientists persist in their never ending quest for better methods of anesthesia (reversible) and euthanasia (not reversible). Lab directors and vets should pay attention, but what does it all come to? Irrefutable proof that CO2 is so inhumane that its use should not merely be unthinkable, but criminalized? Contrary to what some ardent vet supporters would have you believe, the correct answers is a huge and resounding 'NO'. Two lines of evidence are offered: rats and mice will leave a chamber in which the CO2 concentration is increasing before falling unconscious. This suggests the word 'averse' is applicable. If I walk into a room with tobacco or pot smoke, I walk out, so averse, yes, but untold suffering is not implied. The second argument is that rats with a vast number of wires attached and having periodic blood draws show physiological signs of distress/excita tion. All anesthetic/euth anasia agents do this. Some ponder the results. They ask which one causes the least excitation as measured by EKG or biochemically, and declare that whatever agent causes the least (e.g. Isoflurane) is not merely 'best' but the only agent right-minded vet clients should consider.
This involves a breath-taking leap into scientific illiteracy. Again, the 'excitation' phase is normal and occurs just after unconsciousness , so any imagined suffering is just that. Humans in their millions have been put under by anesthetics, all experienced 'excitation' but failed to remember or report it. In the 1950's thousands of humans were put under by anesthesiologis ts using CO2. None died and 92% reported afterward they were 'satisfied' or 'very satisfied' with the CO2 anesthesia. That there are now better anesthetics for humans and animals doesn't mean CO2, considered better than chloroform, is horribly bad. Millions of pigs are anesthetized before slaughter using CO2 and by accident workers have been unintentionally put down the same way the pigs are. No humans report any subjective 'bad trip horrors' or 'pillow over the face' experience. The horrors some imagine comes solely from their overactive imagination. In fact, humans who have been there done that report CO2 as potentially being 'a nice way to go'. After anesthesia is induced, flooding with 80+% CO2 would arguably cause acidosis in the lungs, damaging tissue in the minutes before death, but is this an issue for a suffering, dying, unconscious animal who will be dead in a few minutes? Humans make mistakes, and as with any method, using CO2 could have a bad outcome. If possible, go to a vet, but insist on watching.
Bottom line: I'm willing to agree that the average vet can do a better job of it than the average pet owner. That's 'can' not 'will', however. Vets should make fewer mistakes, but transporting a dying pet to the vet can be traumatic, involving far more suffering than the act of euthanasia. At times, home euthanasia can be vastly more humane. There is some evidence that in the lab or vet setting methods other than CO2 are a bit better. The evidence is weak, academic, and finally irrelevant to anyone concerned with at home euthanasia who doesn't happen to be an anesthesiologis t with access to banned agents. My evidence/reason based conclusion (which nevertheless could be wrong) is that the CO2 method is by far, hands down, the best, the only practical, the most humane way to perform at home euthanasia. If better options exist, that would be good to know. Those who merely want to rail against at home euthanasia per se and the people who consider or do it, however, should put up their own website.
A Purple Finch had shown up on my doorstep unable to use her legs. I kept her safe for a few days, but she was not going to recover.
Her passing was quiet, and I believe painless.
An animal that cannot use their legs requires medical attention ASAP and should be taken in to your nearest veterinary clinic. They will not charge you anything for doing so.
If you found a child/dog/cat/h orse that could not move their legs it is unlikely that you (or any sane, reasonable person) would just keep them at home to see if they get better without medical care. Birds deserve the same level of compassion
- Any animal (including birds) unable to use their legs is likely in a significant amount of discomfort/pain and for this reason alone, veterinary attention should be sought ASAP so that pain relief can be given and the injuries/illnes s assessed
Keeping a severely injured/ill wild bird at home to see if they improve (i.e. without the appropriate medical care that animal deserves) is unacceptably cruel. Try doing that with a human and you may find yourself in jail, try doing it to a dog and you may find yourself in jail. You get my drift.
If you find an injured bird again, PLEASE, place the bird into a cardboard box (with towel on the bottom) with some air holes and transport the bird to your closest vet. Do not attempt to pet the bird (wild birds are stressed by handling, humans are seen as a threat) or feed the bird (different birds have specialised dietary requirements), just get it to the vet safely.
Wild birds, once assessed will either be treated and passed onto wildlife carers to be rehabilitated (rare/endangere d species may be transferred to the local zoo for specialised care) or, if their injuries are too severe, they will be humanely euthanised.
Please explain how you feel the CO2 method is less humane than what I explained in my reply to you yesterday that happened in the "comfort" of an Emergency vets office- when Tinker was handed back to me with her eyes bulged out of her head and blood coming from her nose and mouth? Have you ever had a pet of your own put through something like that? I've used this CO2 method 3 times now on passing pets after promising I would never put a pet of mine through that torture that Tinker went through at the vets office again (2 hamsters and 1 lizard), and all 3 times (even the lizard), the pets showed no pain, no discomfort. They all 3 drifted to sleep during the first anesthetization step, and passed comfortably in their home very quickly with the next step - except for the lizard, which may or may not have passed quickly, he showed no distress - but considering how long they can hold their breath, I kept him in the chamber for well over an hour just to be sure and did a second run as well. When I took the hamsters out, they were still in the same spot they were in (in their little beds they had all their life), eyes closed, body limp and at peace- no bulging eyes, no bedding flung everywhere- just at peace. How can that be less humane than everything I wrote to you yesterday below? If you can give me an even better option for my pets- than please do, but don't tell me what Tinker went through is better. I just have their welfare at heart- I make them a promise when I bring them home- to always spoil them, care for them deeply, and to never let them suffer or be in pain. I always choose the least likely hamster to be picked out by children to love, the ones that may never find a loving home if I don't love them (ie: runts, missing limbs, deformities from birth or from fights at the pet store where they've been in a cage with others), and I just want to keep my promise to them to never let them suffer or be in pain. I am in the US by the way.
I am very sorry that you have had a traumatic experience. No one is accusing you of not loving your pets, certainly not me. Nor would I (or have I) claimed that every single veterinarian will perform the procedure according to the current standard of care. Just as there are less than ideal human GP's out there, there are also less than ideal veterinarians, it is unfortunate, however it is a reality.
As I mentioned in my earlier comments, there are some very simple ways to make sure you choose a veterinarian who will perform a humane euthanasia and as intelligent, caring adults, I am sure you will be able to seek out the care your pet requires in a responsible fashion.
1. Find a veterinarian you feel comfortable with well before euthanasia time, your pet needs regular care so this is the time to find someone you trust
2. Ask how they plan to perform the euthanasia, if you have any doubts about what is explained to you, ask if there is any kinder way. If you are still unhappy, change vets. FYI: sometimes an intracardiac injection is necessary, however this should only be done on an animal that has had anaesthesia induced humanely (i.e. is unconscious when the intracardiac injection is performed)
3. Ask to be present for the euthanasia (if you wish to be)
Whether we like it or not, the facts remain that as our understanding has improved, we now know that CO2 is not a particularly humane method of euthanasia (even if it appears so to you). This is unfortunate, because it is easy and inexpensive, however it is reality. The humane methods of euthanasia, as discussed in earlier comments, are only available through veterinary clinics and as responsible caring owners, we owe it to our pets to seek out a humane end when the time comes. That includes, finding a trusted veterinarian (just like you would search for a good doctor) in your area and being your pets advocate.
Thank you again for explaining all of that to me. I must say again that I live in a very rural area that is way back in the boonies- and the ONLY afterhours emergency vet in the area is the one that I had to take Tinker to because it was late on a weekend evening (which it seems like all severe medical issues happen on a weekend or outside of normal business hours). Tinker had been sick and had been on antibiotics so it was no shock that she had gotton so much worse and required to be taken to be euthanized. But, it wasn't possible for me to take her to my vet of choice. The ONLY choice was the ER vet that was open and they are the ones that I will never trust to do this again. After a few days had passed (after Tinker was buried) and I was finally able to talk without crying, I called to speak to the vet that did this, but they were unavailable and would not return my calls. I wanted to know how they did this procedure and why I was not able to be there for it and why Tinker had blood coming from her nose and mouth and her eyes bulged out of her sockets and hands up to face in a horrified fashion, but I would never get those answers. I will continue to do what I think it best. If it is during normal business hours when I can take them to a caring vet of my choice to be euthanized, then I will- but if it is after business hours and the ONLY vets office to do euthanization is THAT ER clinic, then I will use this method again because I haven't had a horrific outcome like what I had at the vet with Tinker using the CO2. Each time was very quick & painless & I was right there- unlike with Tinker! I will never forgive that vet for doing that to her & I will never forgive myself for letting them tell me I couldn't be there with her for the process. I should have left with her right then & there- but I didn't & Tinker suffered for that! I've been back to that clinic afterhours for pet treatment but I've never encountered that vet to get answers.
With all due respect, I work in the 'real world' and that includes seeing a reasonable number of (lovely) clients who are supremely financially constrained. The issue of cost in veterinary medicine is one I am happy to discuss, however, it is a slight sideline from the issue at hand which is that there is a growing body of evidence to show that the use of CO2 euthanasia is not as humane as it was previously believed to be. While I appreciate that in your opinion, this method is reasonable, your opinion is not supported by the veterinary industry, that is the general consensus of the profession with the training to make well educated decisions in this regard and whose primary focus is the medicine and welfare of non human species.
I genuinely wish that the CO2 method was more humane, as it would enable us to offer a lower cost alternative for the humane euthanasia of our patients and that would be win win, in my opinion.
As for the UK veterinary industry, I work with UK immigrant vets and have a number of Australian colleagues who now work and live in rural areas of the UK. I am not sure where you get your information from, however I can assure you that clinics that would perform an intracardiac injection into an awake animal are the exception, if they still exist. Please contact the BSAVA https://www.bsava.com/ if you have any difficulty locating a clinic that uses humane euthanasia methods in your local area.
As for fees-I don't know about anywhere else,but Ive personally been paid $64 for 10x1.7mls of Baytril,without consultation fee & for 35ml of 1.5 Oral solution of Metacam for Dogs,I was charged $87 & told if I wanted to buy a prescription & order online there would be a $53 charge for that,per prescription-th at doesn't include the drug cost.A call around local vets on a pricing hunt,revealed similar prices.This isn't reflective of the cost price of the drugs,or licensing.This is known clear profit.Leaving people with limited options.The medicine & vet fees here,are known to be over-inflated,& Trading Standards are inundated with complaints-but we've no choice but to pay.Then,as with recent RSPCA cases,the people that can't afford it,inadvisedly home treat pets,without research using over the counter methods,& end up at the Vet, when it all goes wrong,& that's when the RSPCA prosecutes for cruelty.Its a disgusting situation.
I believe in education & a chance for people to make informed decisions & understand your reason for posting.Ive never taken on any animal without research.Howeve r,sadly,as a result of your information,wit h no 'kinder' alternative offered,that didn't involve high Vets fees,I'm now dealing with a guilt-ridden pal,who had no option left-purely due to cost,& now believes she inflicted great suffering on her pet,&is wishing she took out a loan,or did worse,to finance her buddy's passing.
This site gave options.You just implied we were inhumane to our pets.
- RSPCA clinics offer low cost veterinary services in the UK and Australia and will not refuse to euthanise a suffering animal solely on cost grounds
- Most veterinary clinics (including all emergency clinics I have worked in) will euthanise a suffering pet/animal that is in pain, even if owners do not have funds. The owners will still be liable for the bill and payment is expected in the future, however if payment cannot be made upfront, we do not allow the animal to continue to suffer because of this. In Australia and the UK we are bound by a duty of care to relieve pain and suffering. US clinics vary.
- If all else failed, animals can be surrendered as strays and if they are examined and found not to have a reasonable chance responding to treatment (which, I expect would be the case for those desperate enough to consider the CO2 method), they would be humanely euthanised.
Euthanasia that is never paid for occurs at a significant cost to our clinic every year (well over $10K last year) as the costs for us are quite high. For example, a rabbit euthanasia for us will involve a numbing cream is placed on the ear and allowed to take effect (owner cuddle time), IV catheter placement into the vein in the 'numb' ear, drugs for pain relief and sedation given through the IV (if you're going to go, you want to go pain free and happy) and euthanasia solution that also goes through the IV catheter, +/- cremation fees from the mortuary. The medications and euthanasia solution are horribly costly for us to purchase (don't ask me why but 'lethabarb' is $$$), there are clinic/rent overheads, staff time and then if the owner does not wish to take their pet home for burial, we need to pay for cremation (this is a legal requirement by the health department, not optional). It all adds up.
To surrender my pal's pet at the end,would have meant driving 2hrs or public transport for 3hrs,& dump him on the doorstep in a box & walking away.This was a loved family pet & therefore it wasn't an option.My pal wanted to be there at the very end for him,not just spend her life wondering what happened to him.
Sadly-there's now a surrender charge,if you go in person-at least in my town,& surrounding areas.The RSPCA wanted $62 to take a stray Degu I found.I ended up rehoming myself.When I found a stray Puppy,I was charged $185.I paid,as at that time,I could.I couldnt do it now,& would be forced to do a night abandonment,tie her to a gate,& hope to not get prosecuted.
For us-CO2 was the most humane way.I saw no sign of suffering or distress,or attempt to escape,when we used CO2. It was really peaceful & he had slipped into unconsciousness within seconds.The final breath took a while to come,but at the end,it was more agonal breaths,not panic filled suffering.It was done at home,& he was lying in a box,in hay from his cage,with our voices in his ears,& my pal's hand on his side.It was,I believe more traumatic for us watching,as its always so hard to say Goodbye.
Whereever you're from,it seems you've better care available to you.Thank Goodness-becaus e that means there is hope,one day,of worldwide improvement.
I have attempted in my comments to make owners aware of the lower cost options, of ways to to seek out quality care and when necessary, to find a good clinic and surrender their pets (even if the policy doesn't allow free surrender, if you walk in with a 'stray' and refused to take the animal with you, the animal would be effectively, surrendered). As a caring, responsible adult, I am sure you agree that there is no way I can remove every obstacle for every owner, only provide information to help empower owners to make good choices. Ultimately, the onus is on the owners to seek out the solutions in their area and make the effort (transport, financial, time etc.) to ensure a humane end for their pet.
My initial reason for posting is simple, this website whilst not claiming the CO2 method is the most humane method, also does not make people adequately aware of the significant welfare issues associated with it's use and it would be very easy to read the site and end up with the (mistaken) impression that this is a very humane method. Owners who are making tough choices (and especially those who have other options in their area) have the right to know that the method is not considered humane and have some pointers on where/how to access humane euthanasia.
Now as an individual you may feel that CO2 is a humane form of euthanasia (some people still maintain the earth is flat), however the bulk of modern evidence disagrees with you. This is not meant as a personal attack, it is just to say that when a laypersons opinion on any topic varies significantly from the view held by industry specialists/ava ilable research. The individual opinion may not be particularly accurate.
I wish I had your type of world in my country. Because the situations you describe, simply don't exist here...& you certainly can't leave an animal inside a place & walk away without prosecution. You will be found by CCTV shots, etc, as it happens all the time here and is greatly publicized.
I wish there had been a Euthanasia service available at a affordable fee. We were willing to pay what we had immediately - a price quoted in writing a year beforehand, from the animal's lifelong vet, & pay the rest over time, but we were turned down. Policy is Policy. This was not our choice at all. We were literally left with no option.
This site never said it was the most humane way at all - just an emergency possibility, although compared to current methods used where I live, I would argue the 'humane way' hugely. It seems my area lives in the dark ages, with the conscious needlestick into the heart, common practice.
Like I said - wish we had lived in your part of the world at that time.
I thank you for your response. It's Appreciated. I wish you well.
There is now a growing body of literature (references below) that shows that exposure to CO2 is strongly aversive to rodents, likely due to feelings of dyspnea(that is, “air hunger”) and anxiety as reported in humans exposed to CO2. For this reason, many legislating bodies are reviewing their regulations regarding the use of CO2 as a method of euthanasia.
In addition, it should be noted that this method has NEVER been recommended as the most humane way to euthanise a rodent, however as the more humane methods require skills and equipment that are usually limited to the veterinary industry, some labs decided it was cheaper to use CO2. This is a cost based policy, not a welfare based policy. As has been stated, it is also a policy that is under review, given the genuine welfare concerns surrounding this method.
- Carbon dioxide for euthanasia: concerns regarding pain and distress, with special reference to mice and rats. Lab Anim. 2005 Apr;39(2):137-61.
http://www.ncbi.nlm.nih.gov/pubmed/15901358
- Makowska IJ, Vickers L, Mancell J, Weary DM. 2009. Evaluating methods of gas euthanasia for laboratory mice. Appl Anim Behav Sci 121:230–235.
- Niel L, Stewart SA, Weary DM. 2008. Effect of flow rate on aversion to gradual-fill carbon dioxide exposure in rats. Appl Anim Behav Sci 109:77–84.
- Ziemann AE, Allen JE, Dahdaleh NS, Drebot, Coryell MW, Wunsch AM, Lynch CM, Faraci FM, Howard MA, Welsh MJ, Wemmie JA. 2009. The amygdala is a chemosensor that detects carbon dioxide and acidosis to elicit fear behavior. Cell 139:1012–1021. [PMC free article] [PubMed]
Carbon dioxide for euthanasia: concerns regarding pain and distress, with special reference to mice and rats. Lab Anim. 2005 Apr;39(2):137-61.
http://www.ncbi.nlm.nih.gov/pubmed/15901358
This is a well cherry-picked literature review offering. All of the authors are from The Humane Society. Three are from their 'Animal Research Issues' department which 'is working to decrease and eventually end the use of animals in experiments'. If you think this sounds more like PETA than a paper scientists would publish, well, you're not alone. The agenda is conclusion driven and therefore not science driven. To those who like the agenda, it all sounds good.
Makowska IJ, Vickers L, Mancell J, Weary DM. 2009. Evaluating methods of gas euthanasia for laboratory mice. Appl Anim Behav Sci 121:230–235. http://www.sciencedirect.com/science/article/pii/S0168159109002810
They conclude that as CO2 level increases mice leave the area at some point before going unconscious, suggesting they find CO2 aversive. They did not test to see if mice find being held in a vets hand while a lethal dose of a toxin is injected into their body cavity to be more aversive. Isoflurane was the least aversive gas, but not legally available to the public as it would be a hazard to them, and while vets could use isoflurane, they may not as taking the small animal into a back room and injecting it is quicker/easier and/or the cost of the equipment needed to administer isoflurane is not available as it would be prohibitive to buy. So for sure, if you can find a vet who can use isoflurane, go for it (but ask how much first).
Niel L, Stewart SA, Weary DM. 2008. Effect of flow rate on aversion to gradual-fill carbon dioxide exposure in rats. Appl Anim Behav Sci 109:77–84.
http://www.journals.elsevierhealth.com/periodicals/applan/article/S0168-1591(07)00062-7/abstract
Actual science published here. CO2 exposure is aversive to healthy rats as evidenced by their choosing to leave a chamber in which the concentration was increasing. Optimum flow rate was 15% of chamber volume per minute which means reaching 100% CO2 in a bit less than seven minutes. This is useful. That healthy rats leave before dying indicates aversion. No shock and awe here. Don't euthanize your healthy pet. Weigh your dying pet's current/worseni ng prolonged suffering against some CO2 aversion measured in seconds. I have never argued CO2 is the best method imaginable, just maybe the best on a late Friday night.
Ziemann AE, Allen JE, Dahdaleh NS, Drebot, Coryell MW, Wunsch AM, Lynch CM, Faraci FM, Howard MA, Welsh MJ, Wemmie JA. 2009. The amygdala is a chemosensor that detects carbon dioxide and acidosis to elicit fear behavior. Cell 139:1012–1021. [PMC free article] [PubMed]
http://www.ncbi.nlm.nih.gov/pubmed/19945383
Published in Cell, so looking at fear by measuring markers on the cellular level as induced by CO2. Adversion is observable; chemical 'fear' markers arise not too surprisingly as 'fear' and 'adversion' are possibly the same. Again, don't euthanize healthy pets, but death in minutes may be a better death than one lasting hours or days. In the second sentence of this article, preference was given to going to a vet. But taking a rodent to a vet might involve fear and terrors far greater than CO2 distress, so perhaps taking your pet to a vet should be criminalized as animal abuse. But let's endeavor to be sane and go for better choices as there are no perfect ones.
Owners have a right to know that euthanasia with CO2 is not the most humane or painless way to euthanise their pets, even when performed under 'perfect' conditions with well controlled flow rates etc. People who genuinely care about their pets and care about their welfare, deserve to be made aware of this on your page.
A full reply will be too large for one post, so I will break it down a little.
Quoting Eric:
While I appreciate your right to a personal opinion, the authors openly state their bias towards animal welfare. There is no 'hidden agenda', the agenda is openly the welfare of the animals (which is of concern to most owners). As for not being science driven, this is from a peer reviewed journal, not a magazine, it had to pass peer review to be published. Peer review is by no means infallible, however the findings that this method is aversive are reflected in many other research publications from unrelated and less 'welfare biased' groups.
If this was a one off study that was largely refuted by research from other groups, I would have more concerns regarding it's validity, however in light of the general research consensus in recent studies, I feel it is still a study worth noting. Additionally, the journal that published the article has the opposite bias, it's very existence is based on laboratory animal use and non evidence based findings that raised welfare concerns would be unlikely to ever see the light of day in this type of publication.
If I have interpreted the site and your comments correctly, we share the common goal of owners being able to ensure a kind euthanasia or 'good death' for their pets.
I apologise if it has appeared that I wish to discourage anyone from seeking a humane way to euthanise their pets, this is far from the case. My goal, was to provide additional information and make people aware that the CO2 method does have significant welfare concerns and that easily available and kinder methods are available through their veterinary clinic.
We agree, euthanasia CAN be better done at a veterinary clinic. As for horror stories, these are a reason so be a good advocate for your pet and seek out quality care, they are not a good reason to avoid veterinary care. They are a great reason to find a good vet early on in your pets life.
I hear horror stories about teachers, I am still going to put my kids through school, I hear horror stories about surgeons, I am still going to have life saving surgery if I need it. As in any profession there are a few great vets, a lot of very reasonable vets and a minority of appalling ones. Find a good surgeon/teacher /vet... etc.
Many practices, like the one I work in, encourage clients to be involved in the care of their pets right through to the end and are proud to show people through our facilities and where possible, allow owners to be present for procedures if this reduces the stress to the owner/pet. Euthanasia is one of those times when it can be beneficial for both parties to have owners present.
I would far prefer an owner to discuss their concerns with me and be present for a euthanasia (and in suitable cases, be offered home visit euthanasia) than for them to subject their pet to a CO2 euthanasia method. Education, communication and discussion.
Unfortunately, not everyone is able to find an after hours vets office that offers what you describe above. I live in a very small community where the ONLY emergency vet clinic is almost an hour away and if you read my comments that I have made before this one- I had a HORRIBLE experience during the euthanisation of my little dwarf hamster "Tinker". It tramatized not only me, but my husband too & to this very day (3 years later), neither one of us can think of it without bursting into tears. The vet that was on call that evening would not allow us to be present for the euthanisation & she didn't want to use a needle on Tinker because she was so small. So, we gave her the box that we made to take Tinker home in for burial. She carried Tinker out of the room- holding her too tightly with her gloved hands- which upset me to begin with. Tinker was very ill & wasn't going to jump- so why hold her so tightly? Then we heard a vacuum noise for about 1 minute & then she came back in and gave us Tinkers Box with her in it. I couldn't open the box and look at my baby, because I was too upset. When we got in the car, my husband opened the box and Tinkers hands were up to her face, she had blood coming from her nose and mouth and he eyes were bulging out of her head. This was NOT a HUMANE euthansia!! I will never put one of my hams through that again. It only takes once to really hurt, and to think of what Tink went through in her last moments literally tears me up. I love animals more than people and my husband & I have no children except for our pets. I have used this CO2 method to euthanize other hamsters that were ill since then and I controlled it & I helped them go peacefully- no suffering- just sleep and then a little labored breathing, and gone. No eyes bulging- no blood coming out the nose & mouth like that vet did to Tink. Vets in some areas don't think of rodents like dogs & cats, but they should because all little souls are equal.
- Yes indeed, this study clearly shows that rodents find CO2 exposure aversive and that CO2 euthanasia is far more aversive than isoflurane exposure.
- Isoflurane or sevoflurane anaesthesia is standard of care, unless you live in a developing country, your vet will have this.
- If you have ANY concerns about your pets welfare whilst at the vets or the manner in which your pet may be euthanised, discuss them with the vet. Find a new vet if your concerns aren't addressed.
- Ask to be present for the procedure, if you are comfortable to do so.
- Do not allow misplaced fear to drive you to use a less humane and potentially cruel method of euthanasia like CO2 on your pet. Be a responsible adult, talk to your vet, discuss the procedure and be present if you like.
- Emergency clinics or after hours care will be available on evenings/weeken ds in most areas, if required.
It really wasn't nice seeing it when I did my friends rabbit - but we got there. The breathing thing is a natural electrical response, but is more distressing for us than it is for them at that stage. Leave her still inside the bag and let nature take it's course. I found a good YouTube video of mouse euthanasia when i searched small animal euthanasia at home. You might want to look it up and have another attempt. My prayers are with you. Stay strong.
She is still breathing and I fear she will recover as she is twitching again. I have stuck my arm inside and put her unconsious into a small plastic bag to stop her getting any air that may be leaking in.
Not happy about this at all.
It's up to an hour now. Why isn't she still?! I feel sick.
I wanted to use the above one. But was concerned that the little carrier I have to put inside the tank was not suitable as it was a plastic one with slits in the roof. I thought the CO2 sinking to the bottom of the glass tank might not enter the carrier. So I used the glass tank with the reptile feeder method- instead of using the little carrier to put her in, I put the vinegar and baking soda in two large 'cups' inside the tank and left her loose in the tank on something comfortable.
I added the vinegar slowly into the 'cups' to avoid it overflowing. (contin)
I went to my friend to help them. The 'machine' took some setting up - about 2 hrs - & once done,we did a test run with some water. The only mistake we made was pouring the vinegar top fast in the first glass. It fizzed up & covered the tube, but a quick tilt & it was ok. The rabbit was 10yrs old & very ill, & did struggle when that happened, but quickly relaxed with a few soft words spoken to him. We put the sudden fight down to the vinegar smell. He lost conciousness very very quickly. Watching the Agonal breaths was more upsetting for us than him.I checked his eyes & he was 'not there' at that stage. He took his last breath 8mins after starting the process, looking relaxed & in a familar place. The only thing I would recommend is to practice with the vinegar and baking soda. We weren't expecting that much of a reaction so fast. The rabbit was relaxed & slipped away peacefully, surrounded by those who loved him.
MANY thanks for your insightful and well articulated report. We have just used this procedure on 2 very old (almost 3yr old!!) mice. Two sisters and they both developed extensive tumours over the last 6 weeks. The family (including the kids 11 & 14) realised it was time, but wanted a humane way to put them to sleep. Both our kids were involved in this process as a way of learning & coping with life and animals. The procedure was very quick and peaceful for the mice. The sister mice curled up together and were asleep within 90 sec without any distress.
Appreciate all the effort you put into this report.....it certainly saved a lot of angst and worry in our house.
Regards.
I had to euthanize our rat this morning. I will use this method again when the time comes that iI have to. She died peacefully and quickly. In my opinion taking a rat to the vet causes much more distress.
Was it easy? Technique yes. Emotionally..of course not...but I have the peace of mind of knowing she died at home without pain.
For those opposed....why do you think PEOPLE choose hospice instead of hospital.
Eric - thank you.
Sounds like you didn't give the initial step enough time or perhaps had a leak in your chamber preventing the gas to be strong enough to be effective- It can take up to a minute or two for them to become anesthetized. And it is recommended that you have the pet confined in the chamber so you can't view that part. Did you do dry runs before the real thing to ensure your chamber is not leaking? I would recommend doing a few more dry runs to make sure that your chamber is working and maybe re-read the entire instruction list to make sure you did everything correctly. There is no reason why it shouldn't work completely- especially with an ailing rodent. Maybe Eric will have some helpful information to get your friend out of misery. I hope your friend doesn't suffer much longer. Best wishes and I'm so sorry for your little one.
Thank you in advance for your time and reply.
I found this site today because my 10 year old lizard was suffering. I was afraid it wouldn't work since reptiles can hold their breath for so long, but it did! Maybe because he was so weak & just needed a little help. He is no longer in pain & even though I miss him terribly already- I know this was the right thing to do. He was so tired & his eyes told me he was ready to go. It took a little more than an hour & just in case- I did a 2nd run before opening the chamber.
Thank you again!!
I followed your instructions to the letter and he passed from this world peacefully. He did appear to gasp for breath towards the end...but I am sure he was unconscious by then, although his eyes were open, as he hadn't moved for a good few minutes. I know that if I had had to travel to the vet with him that his distress would have been great as he did like being handled.
Thank you
Thank you for putting up such an informative and necessary website. As you mentioned, many small animals' time come after the vet has gone home. Such was the case with one of ours. My wife elected to stay up with the hamster until she past away as others have before. This one had a tough time as she was in distress. When I awoke and noticed my wife still up and emotional at 3:30am I needed to do something. I knew I could use baking soda and vinegar but wanted to be sure of the proportions. Your website supplied the info and I was able to help our pet pass well and allow my wife to finally get to bed at 4:30am.
Let me assure others that if you follow Eric's direction precisely, not close or about, precisely; it is the best way to help your small pets.
Thank you.
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July 1, 2012
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