Sayyiduna Anas (may Allah be pleased with him) reports that the Messenger of Allah (peace and blessings be upon him) sacrificed two rams which were white and black and had horns. I saw him slaughtering them with his own blessed hand, and that (at the time of slaughter) he placed his foot on their necks. And that (at the time of slaughter) he said: "Bismillah, Allahu Akbar."