I brought a newborn brother of mine to the Prophet ﷺ so he could perform tahnik on him, and I found him in an enclosure branding sheep. I think he said, on their ears.
حدثنا حفص بن عمر حدثنا شعبة عن هشام بن زيد
أتيت النبي ﷺ بأخ لي حين ولد ليحنكه فإذا هو في مربد يسم غنما أحسبه قال في آذانها
Bukhari narrated it in the chapter on slaughtered animals and hunting, in the section on branding and marking on the body, hadith no. 5542 etc., hadith no. 2119, and Muslim in the chapter on clothing and adornment, in the section on the permissibility of branding animals other than humans on parts other than the face, from the hadith of Shuba, with the same chain.