Vowing to slaughter a non-pregnant animal and discovering it was pregnant after slaughtering

Q: I made a vow to slaughter a non-pregnant animal, but after slaughtering it I discovered that it was pregnant.

A: It will suffice to fulfill your vow, because you did not know that it was pregnant at the time of slaughtering. Your intention was to slaughter a fat animal, and you did so.May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.