So. breeding works for when it's actively visible in the image (though seems it needs a bit of a cleanup), but this is more about when a character could become pregnant during the act, regardless of if they are currently trying to breed or not. Qualifications as they currently stand are being of the same taxanomic family (so horses and zebras and donkeys and onagers are one example; all the different variety of wolves and dogs another, and so on). Interspecies, due to different mechanics between different characters in the furry fandom, are excluded unless they display some form of concern for breeding ("Please, impregnate me!", "Pull out! It's not safe!" "wear a condom, I don't want to get pregnant").
Basically, if the two going at it COULD give birth, breeding_pair applies. Because it requires a pair, artificial insemination would be generally excluded, though discussion for exceptions where the partner is also the donor (at least one work I know of has two soon-to-be mothers where they both get pregnant by having pairs of both partner's eggs artificially fused together in a lab then implanted inside their wombs, so they can give birth together. Unsure if it works that way or if they have to do a nuclear transplant of the zygote's nuclei from an egg to a donor sperm or what; I'll admit I haven't looked too far into the RL science of it, but it was hot as fuck) are quite possible.
So, discussion, restart! :P
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