Contrary to the statement of that scholar who thinks that marking is mutilation. In this way, due to his ignorance, he has called the Sunnah of the Prophet Muhammad (peace be upon him) mutilation.
Sayyiduna Ibn Abbas (may Allah be pleased with them both) narrates that the Noble Prophet (peace be upon him) offered the Zuhr prayer and ordered that his sacrificial camels be marked with an incision on the right side of their humps, and that they be adorned with a necklace made of two sandals, and that the blood from their wound be wiped away.
Hadith Referenceصحيح ابن خزيمه / كتاب: المناسك / 2575