Musnad Abu Ya'la al-Mawsili 109:100

Ghassan narrated to us, from Hammad, from Abu al-Zubayr, from Jabir, that the Prophet (peace and blessings of Allah be upon him) saw a donkey that had been branded on its face. He said, "Have I not forbidden this? May Allah curse the one who did it." And he forbade striking the face.