Sayyiduna Abu Hurayrah (may Allah be pleased with him) narrates that the Prophet (peace and blessings be upon him) used to say: "A riding animal may be ridden in return for its upkeep when it is pledged, and the milk of a milch animal may be drunk when it is pledged, and its upkeep is due from the one who rides and drinks."
Hushaym and Sufyan bin Habib narrate it from Zakariyya, and in their narration there is the word "al-murtahan", which is not mahfuz (preserved). In one narration the wording is: "When an animal is pledged, its fodder is due from the one who pledged it; the milk of the milch animal may be drunk, and the upkeep is due from the one who rides and drinks."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الرهن / 11206