Now I might stop making slaughterhouse forts and actually try farming again. Plump helmets, here I come.
Before you give up on regular animals, there's something to try as food:
Apparently, eggs are absurdly abundant as a resource. Having just a couple ducks and chickens and taming some wild geese will get you some sort of ovary gattling gun battery that fires out eggs at insane rates of speed. Apparently, they shoot out enough eggs for one or two dozen meals in one sitting, while slaughtering the poultry in the first place tends to only produce a couple meat. That way, you can keep a fort running entirely on cooking eggs for food, and some other means of making booze, including possibly mead from honey, but would still need plants for most booze production, since honey production is unfortunatley very slow.
Hopefully, Toady will come back to some of these raws, and make them have more sensible balancing in the future.
Still, you can now try to run a "slaughter-free" fortress with animals as your food source. Just be aware this may mean problems with having 50 free-range chickens that add to your pathfinding time.
Oh, right, and elk birds and vultures may charge your fortress to try to lay eggs in your next boxes. Be sure to set up a shaft lined with cage traps on the way to your nest boxes, and you can catch some interesting wildlife.
You can even dig out an underground area, let it get covered in grass, and keep your birds down there, where they are surrounded by cage traps in the only path to get access to them.