In Agricola, the Fireplace and Cooking Hearth both allow you to convert animals to food "at any time." Can you use this ability to cook animals if you don't have room in your pastures?
In particular, if you have zero pastures and grab four sheep, can you cook three of them and keep the fourth as a pet (or cook all four), or do you only get to keep/cook one of them, while the other three presumably wander off and get eaten by wolves as you dither over which one to eat first?
Yes, you can cook them directly. From the rulebook, p.9:
1 Sheep (Stage 1): Place 1 Sheep on this space in the Replenish phase (Phase 2) of each round. A player who selects this action takes all the Sheep from the Action space and must either put them into his farmyard or use an Improvement to turn them into food. Sheep that cannot be pastured or turned into Food are returned to the general supply.
The same applies to the other animal spaces.
This is an important tactical option. The threat of having all the sheep grabbed and devoured often forces a player with pastures to pick the sheep up sooner than they might like.
So in your example, yes you may cook three and keep one, or cook all four immediately, at your discretion.
On the other hand, during harvest you may not send a newly bred animal straight to the stew pot if you don't have room.
On p.4 of the rules:
Baby animals and parent animals may not be converted into Food immediately after the birth(for example, if you only have room for two animals of that type); they simply run away if they cannot be accommodated.
