It is narrated from Sayyiduna Abu Hurayrah (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: "When a dog drinks from the vessel of one of you, let him wash it seven times." (b) Ibn Uyaynah narrated it from Abu al-Zinad, and in it are the words walagha (lapped) in place of shariba (drank).
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الطهارة / 1208