I was with Ibn 'Abbas and a man asked him: "Did the Messenger of Allah recite during Zuhr and 'Asr?" He said: "No." He said: "Perhaps he used to recite to himself?" He said: "May your face be scratched! This question is worse than the first one. The Messenger of Allah was a slave whose Lord commanded him and he conveyed (the message). By Allah, the Messenger of Allah did not specify anything for us above the people, except for three things: He commanded us to perform Wudu' properly, not to consume charity, and not to mate donkeys with horses."
Sunan an-Nasa'i Book 28, Hadith 21
← Previous Hadith "A mule was given as a gift to the Messenger of Allah and he rode it." 'Ali said: "If we mate a donkey with a horse, we will have one like this." The Messenger of Allah said: "That is only done by those who do not know."

Sunan an-Nasa'i Book 28, Hadith 20 Next Hadith → "Whoever keeps a horse for the cause of Allah out of faith in Allah and believing the promise of Allah, its feed, water, urine and dung will all count as Hasanat in the balance of his deeds."

Sunan an-Nasa'i Book 28, Hadith 22