No one here claimed it was a good staple.
Just because something is unsuitable as a staple doesn't mean it is an unsuitable feed. I eat apples from time to time, but I'd be very unhealthy if I tried to live on them as a staple.
I eat liver sometimes, but I'd be very unhealthy if I tried to live on it as a staple.
I eat... you get the point.
On the other hand, I can get axolotls or most other species (including myself) obese by giving them a perfect, balanced diet and simply using too much of it. I've seen plenty of extremely obese frogs which have been fed nothing but wild caught insects native to the frogs' natural distribution.
Aside from the 'staple vs. part of a varied diet' argument, there's also the 'it's bad because it's not natural' fallacy. I can (and often do) eat very unnatural things which are very healthy. Most of what modern humans in western countries eat is particularly natural, including a lot of the healthy things we eat. Even most of the fresh fruit and vegetables we eat are barely recogniseable from their natural forms. There are countless examples of animals and humans either being unable to eat something which would be wonderful for them if they could get it, or wonderful for them if they do unnaturally get it.
Just because a particular feed (or food) is too rich or poor in one nutrient or another doesn't mean it's a bad feed or food. Virtually every part of a good, balanced, varied diet is imbalanced if used as a staple. That's the whole point of giving things a varied diet.
...to say something is too calorie dense... goodness, it's a worry if you're that naive and you're being taken seriously by others. We're talking about a carnivorous amphibian here, right? Backing each other up doesn't make you correct, and that's one of the most insane things you could say about a carnivorous amphibian's feed. I can easily get fat or make an animal fat by using nothing but food/feed of low calorie density. Conversely, I can give something nothing but very rich feed/food and make it lose weight, even starve it.
It's especially puzzling that you say it's bad because it's *both* too calorie dense *and* not fully digested. Oh no! They're not getting all the calories out of something that there are too many calories in! (not that there are actually too many calories in it anyway).
Not that it matters in any way, but what is the calorific density of beef heart vs. insect vs. worms? I don't claim to know, but I'd be surprised if it was particularly different, and without any doubt there are perfectly natural and healthy feeds which are both more and less calorie dense than beef heart.
I'm surprised you would insult yourself by using as weak an argument as "Turtles get fat if fed chicken or beef so it's never suitable to give beef to an amphibian' C'mon, even if beef heart is bad for axolotls, that extrapolation makes as much sense as saying that since one brand of floor cleaner is a really great product it will also make a good dietary supplement. What applies to turtles doesn't even apply to other reptiles, let alone a neotenic salamander! Heck, what applies to one turtle doesn't even apply to other turtles - some are carnivores, some are herbivores, some are omnivores and many have very different metabolic rates etc. As said above, you can easily get animals obese by giving them nothing buy their natural and/or ideal diet, just too much of it.
Let's say I have run out of insects or worms and can't get any for a few weeks. Would beef heart be 'suitable' as a stand in? If it puts weight on them quickly might it be suitable to give to a skinny axolotl you're in a hurry to put weight on?
It's sad to see you counter an argument by saying "No, not making it up, because... well, here's some information which is irrelevant to what we had been talking about until I brought this red herring into it"
When signing up I'm pretty sure I read something about this forum revolving around good, solid, information which can be backed up, not just making stuff up and using empty arguments to prove what you want to say. I'm a tad disillusioned.
thank you!