I checked the eternal suggestions/ search and couldn't find anything that looked very similar to this suggestion, so if it's been posted before sorry:
Make a new kind of workshop, perhaps called a 'ranch', where animals could be be 'stored' but still allowed to breed. I've always wanted to have a big meat industry, but keeping enough animals on chains that there is sufficient breeding going on is both currently extremely untidy and a big drain on FPS.
- Ranch workshop that can hold up to X animals.
- Animals inside do not pathfind, would perhaps function like an expanded cage
- Animals inside -do- breed, newborn calves/whatever would begin stored within
- Option in workshop menu to view the animals inside, including their gender, and mark a selected animal for butchering (without having to release it first)
- Possible drawbacks to keep it from being too simplistic:
*Stabled animals require feeding (whereas wandering animals currently 'graze' or however you like to abstract the fact that they don't need food), perhaps an automatic job like looming/tanning and use the animal care labor
*Require an occasional cleaning job to prevent miasma
*Large workshop, perhaps kennel sized or larger
*Only 1 type or similar types of animals stored together ([carnivore]/[benign] must be separate or something to that effect)