Sunan an-Nasa'i, Volume 5, Book 42, Hadith 4338 (DarusSalam) ⓘ
It was narrated from 'Ata, that Jabir said: "we used to eat horseflesh. ": I said: "And mules?" He said: "No
أَخْبَرَنَا مُحَمَّدُ بْنُ الْمُثَنَّى، عَنْ عَبْدِ الرَّحْمَنِ، عَنْ سُفْيَانَ، عَنْ عَبْدِ الْكَرِيمِ، عَنْ عَطَاءٍ، عَنْ جَابِرٍ، قَالَ كُنَّا نَأْكُلُ لُحُومَ الْخَيْلِ . قُلْتُ الْبِغَالَ قَالَ لاَ .
also referenced under: Hadith 4333 (Reference) & Book 42, Hadith 71 (In-Book)