It is narrated from Sayyiduna Arib (may Allah be pleased with him) that the Prophet (peace and blessings be upon him) said: "Indeed, goodness and blessing are tied to the forelocks of horses until the Day of Resurrection. Their owners are helped in (looking after) them, and the one who spends on them is like one who stretches out his hand with charity. Their urine and dung will be, for their owners, with Allah on the Day of Resurrection, (as fragrant as) the musk of Paradise."
These two hadiths are narrated only with this chain; Sa'id bin Sinan (may Allah have mercy on him) is alone in narrating them.