"Do not sacrifice and animal with its ears slit from the front, and animal with its ears slit from the back, an animals with its ears slit lengthwise, and animal with a round hole in its ears, or an animal with one bad eye." (Using translation from Nasāʾī 4375)  

عَنْ رَسُولَ اللهِ ﷺ قَالَ «لَا يُضَحَّى بمُدَابَرَةٍ وَلَا مُقَابَلَةٍ وَلَا شَرْقَاءَ وَلَا خَرْقَاءَ وَلَا عَوْرَاءَ»  

The Messenger of Allah ﷺ commanded us to check the eyes and ears [when selecting an animal for sacrifice] (Using translation from Aḥmad 732)  

«أَمَرَنَا رَسُولُ اللهِ ﷺ أَنْ نَسْتَشْرِفَ الْعَيْنَ وَالْأُذُنَ»