Sahih Muslim Book 22, Hadith Number 4857.

Chapter : It was not permissible to eat the flesh of sacrificial animals beyond three days at the beginning of Islam, but this prohibition was abrogated, and now it is permissible.

Jabir reported that Allah’s Apostle (may peace be upon him) forbade eating of the flesh of sacrificed animals beyond three (days), but afterwards said: Eat, make a provision, and keep it.