It is narrated from Sayyiduna Abu Hurairah, may Allah be pleased with him, that the Messenger of Allah, peace and blessings be upon him, said: A light gray-colored animal is more beloved and superior than two black-colored animals.
Benefits: … It is understood that when an animal is slaughtered in the name of Allah Ta'ala or by His command, attention should be given to the color being grayish, for example: for sacrifice (qurbani), hady, vow (nadhar), or charity (sadaqah).