I have a black Puma, lovingly named Bahgera.

http://beastkeeper.com/pet/137212

He has two red marks, one in his Hitpoints and the other in his Intelligence, but he does have a green mark in strength. I've been lucky with him so far when I explore with him, but I'm kinda reluctant to breed him due to the red marks.

So, what should I do? Should I keep him or should I sell him or leave him in the pound?

I would keep him and research his genetics, even if he have two clearly negative genes he still have a one positive. Who knows which ressessive genes he may hide? With some luck he might turn out to be a good breeder with good ressessive genes even with two negatives already marked.