Due to circumstances I can no longer keep my dog. It is old, 15 years old, and if I give it up to a shelter, I know they will most probably euthanize it because older dogs aren’t considered adoptable. Am I allowed to give my dog up to the shelter knowing that they will do this? He is an otherwise healthy dog.
It is permitted. See sources.
Baba Metzia 32b, Rashba ibid, CH;M 272. If the dog is being given to a shelter run by gentiles then it is permitted, because it isn’t lifnei iver, as you are not telling them to kill the dog. It would only be assisting the gentile, but misayeia l’yidei ovrei aveiro doesn’t apply to a gentile.
Even if the shelter is a Jew it would be permitted, as it isn’t tzar baalei chayim because the way that they are killing it doesn’t cause the animal pain. The actual killing of the animal would be an issur of baal tashchis, however it wouldn’t apply here since it will cost the shelter money to keep the dog alive, and they won’t really be able to make use out of it, therefore it isn’t baal tashchis either. R’ Yackov Ben Naim shlit”a.