Sayyiduna Abu Dharr (may Allah be pleased with him) said: I came to the Prophet (peace and blessings be upon him) while he (peace and blessings be upon him) was sitting in the shade of the Ka'bah. When he (peace and blessings be upon him) saw me, he said: "By the Lord of the Ka'bah! They are the greatest losers." I came and sat down with him (peace and blessings be upon him), but I could not keep still, and I said: May my father and mother be ransomed for you (peace and blessings be upon him), who are they? He (peace and blessings be upon him) said: "They are those with the most wealth, except the one who spends his wealth like this and like this." He (peace and blessings be upon him) said this four times, then said: "And they are very few. There is no owner of camels, cattle or sheep who does not pay their zakah, except that he will bring them (the animals) on the Day of Resurrection, big and fat; they will butt him with their horns and trample him with their feet. Whenever the last (animal) passes, the first will come back, until judgement is passed among the people."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الزكاة / 7284
Sayyiduna Abu Hurayrah (may Allah be pleased with him) said that the Prophet (peace and blessings be upon him) said: "When a man does not pay the right of Allah in zakah (does not give the zakah of camels and the like), he will be thrown down on a flat plain, and those animals will trample him with their feet and bite him with their mouths. When the last of them passes over him, the first will be brought back, until he sees his abode, either in Paradise or in Hell. And when the zakah of cattle, which is the right of Allah, is not paid, he will be thrown down on a smooth, bare plain, and the cattle will trample him with their feet and gore him with their horns. When the last passes, the first will be brought back, until he sees his abode, either in Paradise or in Hell. Likewise, the sheep and goats will trample their owner with their horns and hooves; none of them will be without horns or lame, until he sees his abode, either in Paradise or in Hell. And horses are of three kinds: for one a reward, for one a burden, and for one a covering. Whoever keeps a horse for his own dignity and need, it is a covering for him. Whoever keeps it for jihad in the path of Allah, it will be a source of reward for him; if he lengthens its tether and it climbs one or two hillocks, that too will be a reward for him. And whoever keeps it out of pride and show, and to rise above the Muslims, it will be a wizr (burden) for him." Someone said: "O Messenger of Allah (peace and blessings be upon him)! What do you say about donkeys?" He (peace and blessings be upon him) said: "Nothing has been revealed to me about donkeys except this comprehensive and complete verse: 'So whoever does an atom's weight of good will see it, and whoever does an atom's weight of evil will see it' [Surah al-Zalzalah: 7-8]."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الزكاة / 7285