Sahih Muslim Book 26, Hadith Number 5579.
Chapter : The merit of supplying water and food to animals.
Abu Huraira reported Allah’s Messenger (may peace be upon him) as saying: There was a dog moving around a well whom thirst would have killed. Suddenly a prostitute from the prostitutes of Bani Isra’il happened to see it and she drew water in her shoe and made it drink, and she was pardoned because of this.