From Sahih Muslim (Hadith 793):
Ja'far b. 'Amr b. Umayya al-Damari reported on the authority of his father who said:I saw the Messenger of Allah (ﷺ) take slices from goat's shoulder and then eat them. He was called for prayer and he got'up, leaving aside the knife, and offered prayer but did not perform ablution
Reference: Muslim 793