Reptile & Amphibian Forums

Hi guys,
I have a neonate Naja nigricollis from this year. It is offspring of a friend of mine and he told me when I bought the animal that he ate perfectly.

Now the first feeding was indeed no prob. He ate a fuzzy mouse that I offerd alive. But then the strangest thing happend. I will jump ahead in time to last week. I had put an jumper mouse in the cage. As he is most active at the fall of dark I was in the room at that time. He was cruising the cage like a mad man and when he came across the mouse just stopped for a moment and went on. Well the next day the mouse was dead. I had put another mouse in the cage and left the dead one also in the cage. The living mouse began to eat the dead one and had eaten his head. The next morning the eaten mouse was gone. I have tested it last night again with a fuzzy mouse that I gave still living. He came across it but nothing. After some hours I killed the fuzzy and put it back in front of the hidebox. After 15 minutes the dead fuzzy was gone.

Is there anyone who has also animals that kinda refuse living prey and only eat dead prey?? In the 16 years that I keep snakes I never have had seen this one before LOL They keep amazing me.

Cheers niek

Not all that strange... I've seen many snakes in captivity that prefer a prekilled prey item to a live one. A lot of the cases I can think of off of the top of my head have been cobras also.

well oke that they take dead prey easy cause of less use of energie is one thing. But completly refusing living prey is something that as far as I know is not that commen.Especually when you come to think about the feeding responce cobra´s have. They go completly insane when a prey is entered the cage and will strike at everything that moves. At least that goes for the rest of my cobra´s . But this nigricollis is not going insane at all when given a mouse. And that for an African Elapid?? not that commen to me..but hey maybe I´m wrong hehhehe

That Naja you got from your friend may be "imprinted" to take pre-killed food items. Not at all un-common.

mmm oke

well then I just found it remarkable that he did all this

I can't say specifically because I don't believe I've EVER had to give live prey to a cobra (and never feed live if I can help it), but I've had plenty of snakes that were fed pre-killed from hatching/birth (or even just for a few months) that will run and hide if you drop in a live mouse.

This is a GOOD thing. Stick with the pre-killed and don't sweat it.

I agree with Larry 100%. Why risk it?
-----
Tim Cole
www.Designeratrox.com/
www.AustinReptileService.net
www.AustinReptileExpo.com/
~~~~~~~~~~~~~~<
Conservation through Education

don´t understand me wrong guys ...I never said that this feeding thing was a problem at all.Just was currious if there were any other keepers who had this.
Th reason why I feed almost all my hots living prey is that they are way more capable in killing a mouse .. When feeding rats I usually will kill them and when still shocking throw them in. Th strenght of a mouse that gets pinned by any of my cobra´s is not enough to damage the snake. And also I have never seen a mouse live longer then a few seconds. Rats as I mentioned would have te power to damage so they are offered dead in most cases.

I know allot of keepers are pro pre killed and anti living prey but I have a other point of view but as long as my animals are healthy and 100% intact I will not change my mind.

>>...as long as my animals are healthy and 100% intact I will not change my mind.

Sounds like you'll be an "after"... (Some of us switched to pre-killed "before" one of our snakes lost an eye, and some of us switched "after".)

Until recently, I would have said that it was no problem to feed live to rattlesnakes because they strike and let go. That was before I put a live mouse in with a mojave rattler and watched the following:

Mouse wanders around cage
Snake pursues mouse
Snake bites mouse
Mouse flies up in the air
Snake retreats to one end of cage
Mouse lands at other end
Mouse looks around for a second
Mouse RUNS to the other end of the cage and starts biting snake on the side
Snake strikes again
Mouse lands halfway across cage
Mouse runs straight back over and continues biting snake until mouse dies

It happened that the mouse was not able to penetrate the scales on the snake's side, the eyes and the mouth are not as well protected...

In the late 70's I lost a Southern Pacific Rattlensake to a live rodent. That was the last time I fed live when not needed. I guess some people learn more quickly than others or don't mind putting their animals at risk. Lots of experienced advice available on this forum to those willing/wanting to learn without making the same mistakes over and over again...

One of my ex-girlfriends insisted on feeding her adult boa live rats even after I told her the downside to this. A couple months later she called crying because she came home to a butchered, dead snake and one fat rat. I was so angry at her for treating the snake this way I said " I told you so", and hung up on her.
-----
Tim Cole
www.Designeratrox.com/
www.AustinReptileService.net
www.AustinReptileExpo.com/
~~~~~~~~~~~~~~<
Conservation through Education

well guys,

The cases you two mentioned I couldn´t agree more. You both talk about rattlers and a boa. For the boa, those type of snakes are lookiing so big but are just little kids.. They get scared of a mouse or rat that moves a bit to fast towards them and only will try to hide when attaced by a rodent. The same counts for rattlers, bitis sp etc for all I care. BUT as I mentioned before, I keep Elapids. They really kill the prey ..and when I say kill I mean kill.. Only for the nigricollis this is different but all other cobra´s I have go crazy when a rodent comes inside the cages and will strike more then 10 times and at the same time throw the rodent through the air. The poor rodent doesn´t even have a chance of trying to bite cause he doesn´t even know what hit him..

so Don´t worry guys,, I give animals that I keep that are not so "brave" dead prey but for my Elapids thats a different story

>>...The poor rodent doesn´t even have a chance of trying to bite cause he doesn´t even know what hit him..

Until that one time the mouse happens to see it coming or gets stuck on a fang or any of a dozen other things that "will never happen" happens. Biting 10 times just means 10 times as many chances for something to go wrong.

I used the rattler as an example for two reasons:
1) They are faster than cobras (striking)
2) That didn't keep something totally unexpected from happening. This wasn't a hungry mouse left in the cage overnight, it was ticked at being bitten and went to war.

And just to be clear, I don't have any kind of moral objection to feeding live prey. I feed pre-killed because it is safer for the snake AND easier for me. I feed live to anything that I have problems getting to eat dead. I have, on occasion, fed live now and then just to see or demonstrate the venom effects to someone else. I don't do that often enough to worry much about the chances of something going wrong.

If you're willing to take that chance, and you don't mind the possibility of an injury now and then, that's fine. It's a chance the snake would be taking in the wild, so arguing that it's WRONG for you to feed live doesn't make much more sense than the people who say you shouldn't keep snakes at all because it's somehow cruel to feed one animal to another. But argueing that it won't happen, because you haven't seen it happen yet is like those guys that free-handle their gaboons. No matter how many times they have seen something NOT happen, it doesn't change the one time I HAVE seen it happen.

(And no, I've never SEEN a cobra lose an eye to a mouse since I've never even seen someone feed live to a cobra, but I have had almost the same discussion with people who own boas. "He always grabs them so fast they don't know what hit them." Those boas with mangled noses that come into our refuge come from somewhere...)

...cant believe this topic prodded me 2 post...but..i find it incredible....how most folks arent nearly as fascinated as i am to watch [for the umpteeth time]....that perfect geometric strike....the wrap &-or envenomation...the rx to said & time to death/ingestion....a glimpse at what happens in the crevices & logpiles worldwide...so do it Niek....but dont expect approval here or elsewhere....& be grateful for mere tolerance! A large naja clamping down a large squealing Rattus is why id risk keeping such a big naja to begin w/ !!!

Snake and setup: $500.
Rat: $2.
Watching a snake be a snake: priceless.

Having a $2 rat destroy a snake: Embarassment and shame.

I know of one instance where an individual pre-killed a mouse (not even an adult mouse) and didn't quite get it all the way killed... the result... a dead suphan cobra. If you're going to feed live, expect to have a few injured snakes due to stupidity.

I agree.
I think most people who posted here forget that we are talking about CAPTIVE reptiles.

It doesn't matter if the snake is c.b. or w.c., venomous or non-venomous, they are still CAPTIVE, i.e. caged, confined, etc.

Doesn't matter in the wild, they normally eat live prey items,(some are scavengers) the snake (predator) is NOT confined by a cage, exhibit, etc. They (the prey item) can still get away, or the snake can escape a rodent that wants to retaliate.

I have known folks that have had a 2 dollar rodent kill a 500 dollar snake, so, do the math. Your reasoning is skewed, and I think you didn't understand Jim Harrisons "final answer".
You are making a mockery out of this post by coming back again and again with challenges, with no evidence or proof to back it up. It's only conjecture on your part. Listen to people with experience and reason, and them maybe, you'll see the light.

I have personally witnessed hundreds if not thousands of interactions between snakes and live prey. I have not seen any injuries to a snake under these circumstances. Not to say it can't happen, everyone seems to have a story of a "friend" that suffered this. My thought may be that proper monitoring is needed. Snakes don't kill with long range weapons whether in captivity or in the wild.

I am not trying to continue this thread, but will respond to YOUR challenge. Mine was a question, therefore does not require proof. What was originally disappointing was the lack of scientific method (which rarely has a "final answer" and is not about conjecture). What I realize now is that this is an opinion forum and not a scientific forum. If only popular opinions are acceptable than I have seen the light.

Placing a live mouse that is believed dead in with a snake and placing a known live mouse in with a snake are not identical scenarios.

redtailboa.net/forums/feeding/15585-thinking-about-feeding-live-welcome-live-pile.html

Follow the link. Sure it is a rat in this instance and a red tailed boa, but I think it still illustrates that feeding live to a snake is not the best idea. If you don't want to listen to those that have "been there" and "done that" then you'll just repeat the mistakes that others have made instead of learning from them.

You keep bringing up scientific background and the scientific method, but this is a case where the evidence is such that you can draw a valid conclusion from the evidence that is already out there. You don't have to have a fancy experiment to see that feeding live can harm your snakes.

You chose to take the snake in as a captive animal. That makes you responsible for the wellness of the animal. If you chose to watch your snake kill its own prey so you can get your jollies you need to find something better to do with your time than risking your captives.

First, some clarification. I do not feed live prey. I worked at a facility that did. The success rate (lack of harm) was perfect. These people did have the the experience and knowledge to make this choice.
Second, I can support many opinions by linking to a sensationalist website. This is a technique used by animal rights activists to support the view that certain breeds of dogs are too dangerous for private ownership. It is still just an opinion. And this is only one example of misuse of information.
I have expressed approval for sharing opinions, as long as they are recognized as such. The things I type are as obvious to me as the things you type are to you.
Captive care of any animal is never a sure thing. Minimizing realistic dangers is an obligation. Having perspective of these dangers is something else altogether.

You can lead a horse to water, but you can't make him drink. Guys you are wasting your breath. He obviously knows that there is no way an unforeseen accident can happen, so he is willing to take the chance. I would save the energy until it's time for the I TOLD YOU SO.

"These people did have the the experience and knowledge to make this choice".

Again, people that somehow KNOW that an unforeseen accident won't occur and are willing to take the chance. How experience and knowledge has anything to do with this is beyond me, but they KNOW.

If this is a critique of my post it makes no sense and is inconsistent with the statements made. That is about what I have learned to expect on this Kafkaesque board.
Using this logic justifies everything PETA stands for. No more ownership of animals because "something" is bound to go wrong somewhere, sometime which could harm the animal or a person. Check the "statistics" and methodology they use.

Umm, no it has nothing to do with PETA. It has to do with people giving you safe advice, from their own knowledge, that you can't seem to grasp because of the "it's never happened before"
attitude. Take with it what you will. If you want to take the chance, so be it, noone can tell you how to care for your animals. I would suggest not posting the day one of your snakes gets injured by a live rodent. If you do, I'd get ready for the flames.

swoooosh! (the sound of flames!)
LOL!

That was great! Having stated that I don't feed live prey to my animals makes all this unlikely however. You guys clearly are more adept at irrational flames (and take pride in this)than believing that a popular opinion held by a specific population does not qualify as TRUTH. Political, scientific, and religious history show more contradiction to this notion than confirmation.

Flame away, I could care less. Why should I expect a rational, consistent, factual response where none have been found before?
I have stated before, this is an opinion forum. If the use of insulting language is the way anyone wants to make a point, that is their perogative. I have not yet stooped to this.

So enjoy yourselves, continue to ignore legitimate inquiry by replacing the comments of others with what you wish they said so you can respond with predetermined answers.

I have 1.2 Naja nigricollis nigricollis which are about 5 months old. They have refused live prey since I got them. Even now that do not take the prey when I put it in the cage. I drop the dead mouse in and it is gone in the morning.

Not too much to worry about. As long as they are eating - not a problem.

Cheers.

Niek: The advice you are getting from the others does not seem to be registering, & I can't figure out why. You have snakes that you paid good money for. Most, if not all, will accept pre-killed prey items. Pre-killed prey items will not cause damage to your snakes.
Live prey items are certainly capable of that, even not quite weaned mice. You do not have to feed a supply of mice & rats that are stored in the freezer. Buying them in large quantities is cheaper.
One other thing: If you ever expect to sell any of your snakes, you will have to greatly reduce the price for any that are scarred.

With all that said, for the safety of your snakes, as well as for economic reasons, feeding pr-killed is much better than feeding live.

~~Greg~~

Well Greg,

I understand that giving dead rodents will erase the risk of damaged snakes. And as I mentioned before I allready do this with rats. A few cobra´s here are still youngsters so they eat fuzzy mouse.. I know they´ll eat dead but a fuzzy is not that harmfull isn´t it.

Your point about buying large amounts of frozen food is cheaper is correct. But ( yeah I am a pain in the ass lol) I rather breed my own feeders. Killing them and freezing them is something I allready do when the rat population is growning like a weed. When I breed my own feeders I know what went in the animals as food. With frozen food you don´t know anything. Even with living food bought somewhere else you have a bit of a risk. I bought at a show 100 mice. My intention was to use about 60 of them for breeding .. Unfortunatlly most of them didn´t survive for more then 2 weeks.
The animals are kept in clean cages and have allways acces to food and water. I am telling this to make clear that those mice were not good ( duh) and when given to a snake will also not be good food.

But to make an end on this subject .. I will stay prekilling rats as I used to. And will start offering prekilled mice to the rest of the animals so I won´t get damaged pets.

cheers Niek

Does any research exist as to the effect of feeding pre-killed on the venom apparatus of a snake? I have heard anecdotes that such animals have less harmful bites. Scientific data would be more believable.

Someone that claims that feeding prekilled items makes for a less potent venom is probably talking out of their league. Frozen/thawed mice provide an sufficient diet for the animals to live, grow, reach adulthood and successfully reproduce. If it provides a complete enough diet for the completion of the life cycle, it surely has a complete enough of a diet to manufacture venom properly. From what I've witnessed in snakes this does not hold true at all.

that would be indeed out of the question. It´s even so that a baby cobra that has just hached has a fully working venom production and is even when haching capable of delivering a dangerous bite. Tha think that I am in doubt about is feeding dead food to snakes with haematoxic venom. cause of the lack of bloodflow the venom will stay put on the place of the bite. But as I can remember (correct me if I´m wrong) there has been a research about this and the outcome was that there was no effect on digestion with these animals.

I think the idea is more along the "use it or lose it" way of thinking.

>>Frozen/thawed mice provide an sufficient diet for the animals to live, grow, reach adulthood and successfully reproduce.

I don't think there was any implication that it was because of a dietary deficiency. The idea was that the snake was somehow able to become more efficient by wasting less energy producing venom if it was never needed. Whether it is true or not, I have no idea.

Yes... but that is thinking along the lines of lamarckian evolution and it doesn't hold water. The likeliness of this being true is very very very slim, and it sounds like something thought up by an armchair biologist.

>>Yes... but that is thinking along the lines of lamarckian evolution...

Actually I was thinking more Pavlovian, if you will. I didn't mean to imply that the snake might magically develop some new ability, but rather that perhaps one had evolved over time. Think more along the lines of a human that moves furniture for a living developing larger muscles where a pencil-neck like myself need not waste energy on such things. The effects are short term but the mechanism is purely darwinian.

Ok. So we know that evolution acts on a species not an individual. It can select (for or against) an individual (this is darwinian). Keeping that in mind; wouldn't the mover starve to death if he took a vacation (brumation) and couldn't pick up large enough prey items. ...sorry; that doesn't make sense I know but I'm a bit lost on this use it or lose it theory. Please, expound on this.

The original question was about snakes losing venom delivery ability if fed F/T prey. The question was not about the nutritional value of F/T or a trait passed on to offspring (evolution or genetics).
The physiological concept of "use it or lose it" is called atrophy. That strapping mover can lose livelihood after an illness or injury, because of atrophy. That is why we have disability insurance.
Whether venomous snakes lose effectiveness when removed from the natural situation of envenomating prey is still the question.

THEY DON'T. There is no evidence to suggest otherwise.

Atrophy is something that happens to muscles/tissues that don't get used and/or get a lack of nutrition. It is not something that occurs in a venom gland, venom apparatus etc. Just because a snake eats frozen thawed prey does not mean that it isn't using its venom apparatus.

I've had snakes that have eaten frozen thawed prey for over 8 years and when I offered them a live weanling rats due to having a lot of extra (restrained by tongs feeding them just as I would frozen/thawed) the snake was still able to kill the prey item no problem.

Saying that venom structures atrophy and become ineffective is making leaps and bounds and is over applying principles that don't fit the situation.

Do you really think that a structure such as a venom glad that took such a long time to evolve is actually going to go away within a generations time due to non-use? Not hardly.

Thank you. The anecdote about feeding frozen/thawed for 8 years with no loss of killing power is telling. I do have to respectfully disagree that the delivery of venom does not involve muscles/tissues.
Also, I was wondering about the biological activity of venom that sits in a gland unused. Is it reabsorbed and recycled? Or perhaps it is used on prekilled prey.
Answering these questions scientifically would involve doing LD50's on two population of snakes (maybe the only useful purpose of LD50's). The answer is impractical though except for understanding the affect of captivity on snakes.

I do have to respectfully disagree that the delivery of venom does not involve muscles/tissues

Ok, and I'll have to respectfully tell you to stop putting words into my mouth that I did not say... Nowhere in my post did I say that venom delivery does not involve muscles/tissues.

What I did say is...

Atrophy is something that happens to muscles/tissues that don't get used and/or get a lack of nutrition. It is not something that occurs in a venom gland, venom apparatus etc.

Just b/c the glands aren't injecting venom into prey at regular intervals does *NOT* mean that they are not active. They are in the simplest sense highly modified salivary glands (and in some snakes, less so). They are not going to atrophy just b/c they aren't "used" in captivity. Just b/c a snake doesn't use it's venom delivery apparatus for killing doesn't mean it doesn't use it. I'm sure anyone here on this forum that has watched pitvipers eat will tell you that they use their fangs etc to eat with. Even my elapids do. Once again, this is a thread of over applying concepts where they do not belong.

This reply just leaves me with more questions. But I guess questions are unwelcome. Thank you.

All of our animals on the venom production line are fed prekilled/frozen mice and rats. Some have been on line for 25plus years with no effect on venom production or venom makeup.

Jim Harrison

Jim's answer should end this discussion.

Randal Berry

Yes, thank you. The answer to MY question is that no respondent is aware of SCIENTIFIC DATA regarding feeding F/T prey on venom delivery. This is an imposed "lifestyle change", and whether changes occur that are anatomical, physiological, or biochemical is unknown. Some graduate student can do a study, but again the answer would be arcane.

We published a short paper on effects of captive breeding on venom production (yield,toxicity and composition) in Naja kaouthia. It was in 1995 Toxicon issue that I can not remember right now. All animals in the study were feed F/T rodents. It had no effect on venom.
For our customers we have to keep standards and one is tracking venom yield/composition. I hope this helps a little in anwsering your question.

Jim Harrison

Yes, thanks. This narrows down the field considerably. Feeding F/T has no direct affect on venom production and composition (as cited by your research). These animals do get "milked" regularly I assume. If I am not mistaken, this is kind of a "semi-passive process" for the snake which also allows the opportunity to replenish the supply. The next step that I am looking for is whether complete lack of use does anything. The process of eating solid food may not meet this criteria, which I can accept if proven.
But again, thanks.

What forces at play would cause such a thing? Everything mentioned thus far has been reasoned to be negligible, and if Jim mentioning venom composition data from his captive animals isn't "scientific" enough, I don't know what is. Not trying to come off as rude, but I just don't know where this is going.

What specific questions do you have about venom delivery systems and the forces you think are at play that are strong enough to have a measurable effect on animals in captivity regarding venom production, and what would satisfy you that even when fed frozen thawed for years that they still have intact venom apparatuses that hasn't already been mentioned?

Overuse, underuse, and misuse can have profound consequences on many organ systems and physiological processes. I don't pretend that this is an earth-shattering question. I just wondered if anyone has quantified the effect.

Just because a snake doesn't use it's venom apparatus to kill its prey does not mean that it isn't still used (as mentioned earlier). The apparatus is still used in eating/swallowing. Just this stimulation alone should be enough to keep the muscles and associated structures from getting atrophied.

As far as the glands go, I'm not sure if the venom is broken down and recycled, if old venom drips down the digestive tract in small quantities to make room for new venom, or if it is just stored...

If you are genuinely interested in the process that takes place, there is TONS of scientific literature regarding glands in animals. There are glands in many snakes (both venomous and nonvenomous) that we currently don't know the function of.

What process takes place is not all that important, as we have demonstrated that whatever happens, they still are just as much of a threat after eating frozen thawed prey for years as they would be if they had eaten live prey their whole life.

"The next step that I am looking for is whether complete lack of use does anything".

Who says that a snake doesn't inject venom when it's fed pre-killed food?

"What forces at play would cause such a thing? Everything mentioned thus far has been reasoned to be negligible, and if Jim mentioning venom composition data from his captive animals isn't "scientific" enough, I don't know what is."

I can help with this. The scientific method is not about reasoning through a concept but the use of controlled experiments. Results are often published in peer reviewed scientific journals.

I don't even know how "forces" are used to describe biological phenomenon.

Now that I have been turned into a nit-picking idiot, I apologize. I am sensitive to having my scientific acumen challenged. Let's let this die and return to the purpose at hand. I will defer 100 percent to your practical knowledge of keeping snakes. What I have learned is to view this as more art than science.