Hisham bin Zayd reported,

We entered upon the Messenger of Allah ﷺ at a pen while he was branding sheep. He said, I think he said, on their ears.

Muslim 5556

Sahih

و حدثني زهير بن حرب حدثنا يحيى بن سعيد عن شعب

ة حدثني هشام بن زيد قال سمعت أنسا يق

ولا دخلنا على رسول الله ﷺ مربدا وهو يسم غنما قال أحسبه قال في آذانها

مسلم 5556صحيح
Contents
Reference
Commentary
Ayat
Collection
Sahih Muslim
Book
Clothing and adornment
Chapter
Permissibility of branding non-human animals on other than the face and its recommendation for zakat and jizya livestock
Numbering
Darussalam 5556
Muslim 5556