It is narrated from Sayyidah Umm Salamah (may Allah be pleased with her); she said that the Messenger of Allah (peace and blessings be upon him) said: "When the ten days of Dhu al-Hijjah begin, whoever intends to offer a sacrifice should not take anything from his hair or his nails."
Hadith Referenceالمعجم الكبير للطبراني / مسند النساء / 19866