Uhh! Why are they so gross!?

So I just spent 10 minutes fighting to get a dead bird out of Bianca's mouth! Second grossest thing she's done. Last summer I had to do the same thing with a mouse she caught - but that one was more intake.
Why!!? Why can't she just be a cute little puppy? Why does she have to do gross things like that? :( She's such a little punk sometimes. Last weekend I put her outside - she started taunting the neighbors dog [which she does often] I told her to leave him alone - she then walks over to a tulip - takes the bud in her mouth - rips it off - then spits it out and walks off. Such a punk. Grrr.
Misha is too fat and short to catch birds and mice. But Bianca - she's like a mix between a Cheetah and a Gazelle. Maybe I should try to fatten her up? Then she wont be able to move so quick. Hmm....