Mishkat al-Masabih 20 Game and Animals Which May Be Slaughtered كتاب الصيد والذبائح 64

وَعنهُ حَرَّمَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ يَعْنِي يَوْمَ خَيْبَرَ الْحُمُرَ الْإِنْسِيَّةَ وَلُحُومَ الْبِغَالِ وَكُلَّ ذِي نَابٍ مِنَ السِّبَاعِ وَكُلَّ ذِي مِخْلَبٍ مِنَ الطَّيْرِ. رَوَاهُ التِّرْمِذِيُّ وَقَالَ: هَذَا حَدِيث غَرِيب

He said, referring to the day of Khaibar, that God’s messenger declared domestic asses, the flesh of mules, every beast of prey with a fang and every bird with a talon to be unlawful. Tirmidhi transmitted it, saying this is a gharib tradition.