So. A little update on my "pit" strategy.
The cat population was low so that pit is almost empty, the others are moderate except for horses. Horses were MASSIVE so I thought I'd butcher some ... but I couldn't keep count very long.
Guess why? That's right. For me to butcher the animals I can't lock the doors, dwarves have to get in and out after all. It doesn't matter if a horse or two escape I don't care, I'll just mark the escaped ones for butcher. The problem is that the damned children run in and out of the stables and look at the animals, letting them all out and chasing them around the fortress.
I spent over 200 wood on that stable!
Update: SO after half the horses escaped (and i couldnt keep track of who was who) i ordered them all back into the pit. Little did I know this meant that after the dwarves had dumped the escapees into the pit and i would later unlock the door to allow them to get some to butcher.. dwarves would swarm into the pit, grab horses and drag them up the stairs, pushing and shoving only to throw them back into the pit on other dwarves who came to get animals to throw into the .. you get the picture.
So the escapees were free to run out the wide open door once again. I ordered every last one of the horses that left the stable to be butchered ... so.. I think I halved their population.
Clearly this is not such an effective way of breeding that I thought.