Sahih Muslim 2117
Sahih Muslim · Book 37: The Book of Clothes and Adornment · The Prohibition Of Striking Or Branding Animals On The Face
Jabir reported that there happened to pass before Allah's Apostle (ﷺ) an ass the face of which had been cauterised, whereupon he said:
وَحَدَّثَنِي سَلَمَةُ بْنُ شَبِيبٍ ، حَدَّثَنَا الْحَسَنُ بْنُ أَعْيَنَ ، حَدَّثَنَا مَعْقِلٌ ، عَنْ أَبِي الزُّبَيْرِ ، عَنْ جَابِرٍ ، أَنَّ النَّبِيَّ صلى الله عليه وسلم مَرَّ عَلَيْهِ حِمَارٌ قَدْ وُسِمَ فِي وَجْهِهِ فَقَالَ " لَعَنَ اللَّهُ الَّذِي وَسَمَهُ " .
Allah has cursed one who has cauterised it (on the face).