Sayyiduna Anas (may Allah be pleased with him) said that the Messenger of Allah (peace and blessings be upon him) sacrificed two rams that were greyish-white in colour and horned. He (peace and blessings be upon him) placed his foot on their necks and said, 'Bismillahi wallahu akbar' (In the name of Allah, and Allah is the Greatest), and slaughtered them with his own hand.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الضحايا / 19007