Treatment of hypothetical alien life

I wonder about this situation/thought experiment. Part of this post is to have a discussion but also so that you can perhaps help me understand my own feelings better on this. Suppose we find alien life on a very biodiverse planet that ranges in intelligence all the way from the equivalent of apes, dolphins, dogs, pigeons, fruit flies, microbes etc. How should we treat it?

If we find microbes on Mars I am pretty sure we will be experimenting on them in the lab and that will be mostly uncontroversial. But what if there are "dogs"? Should we experiment on them to understand their biologyr? Or even without experimentation, what about just kidnapping them and putting them in a lab to study or zoo or whatever? Surely finding life on an alien planet would be the largest scientific discovery that should be studied, but how?

Arguments in favor of experimentation would say that we do it anyway on animals on Earth so what's the difference. Arguments against it are all current arguments against our Earth animal's treatment plus a few along the lines of whether we would like advanced super alien species experimenting on us. Although as for that I am not sure if that is too relevant, I don't think we treat ants better or worse relative to how they treat other inferior species.

I am not against dissecting a mouse or experiments like giving a lab rat cancer to understand it and find treatments etc but somehow it feels "wrong" to me to go to Mars, find a "rat" encage it and experiment upon it. I can't put my finger on it exactly how or why though. And if we agree that it is somewhat uncontroversial to experiment on Mars microbes, why is it that different to experiment on "rats"? Is it the consciousness level? What about "fruit flies"? All that in itself is hard to pinpoint.

Is there any international policy on this hypothetical scenario? Do the US or other countries have any sort of official stance on this? Or is it the case that if we find microbes on Mars we just decide on the spot what to do and each country actor does whatever?