The consumption of donkey and mule meat is forbidden in all Islamic schools of thought. It is narrated from Jabir (r.a.) that he said: “The Messenger of Allah (s.a.s.) forbade the consumption of donkey meat during the Battle of Khaybar, but permitted the consumption of horse meat” (Bukhari, Zaba’ih 28; Muslim, Nikah 30).
Based on this hadith, Hanafi jurists such as Abu Yusuf and Imam Muhammad, as well as Ahmad ibn Hanbal and the majority of Islamic scholars, deem horse meat permissible. However, Abu Hanifa considered it makruh tanzihan (disliked but not sinful). Imam Malik, on the other hand, considered horse meat forbidden, basing his view on the hadith: “The Messenger of Allah forbade the consumption of the meat of horses, mules, donkeys, and any predatory animal with fangs” (Ahmad ibn Hanbal, 1/147, 244, 289; 4/89, 90, 127).
Another reason for Abu Hanifa and Imam Malik not deeming horse meat lawful is the verse: “And He created horses, mules, and donkeys for you to ride and as adornment” (Qur’an, Surah an-Nahl, 16:8) (Source: Shamil Islamic Encyclopedia).