It is narrated from Sayyiduna Asim bin Adi (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) permitted the shepherds to throw (the pebbles of two days together) in one day and leave it on the other day, and to graze their camels.
Hadith Referenceصحيح ابن خزيمه / جماع أبواب ذكر أفعال اختلف الناس فى إباحته للمحرم، نصت سنة النبى صلى الله عليه وسلم أو دلت على إباحتها / 2978