Sunan Abi Dawud: Book 9, Hadith 13

Narrated Abdullah ibn Umar: The Messenger of Allah (ﷺ) wrote a letter about sadaqah (zakat) but he died before he could send it to his governors. He had kept it with his sword. So AbuBakr acted upon it till he died, and then Umar acted upon it till he died. It contained: “For five camels one goat is to be given; for ten camels two goats are to be given; for fifteen camels three goats are to be given; for twenty camels four goats are to be given; for twenty-five to thirty-five camels a she-camel in her second year is to be given. If the number exceeds by one up to seventy camels, a she-camel in her fourth year is to be given; if they exceed by one up to seventy-five camels, a she-camel in her fifth year is to be given; if they exceed by one up to ninety camels, two she-camels in their third year are to be given; if they exceed by one up to one hundred and twenty, two she-camels in their fourth year are to be given. If the camels are more than this, a she-camel in her fourth year is to be given for every fifty camels, and a she-camel in her third year is to be given for every forty camels. For forty to one hundred and twenty goats one goat is to be given; if they exceed by one up to two hundred, two goats are to be given. If they exceed by one up to three hundred, three goats are to be given; if the goats are more than this, one goat for every hundred goats is to be given. Nothing is payable until they reach one hundred. Those which are in one flock are not to be separated, and those which are in separate flocks are not be brought together from fear of sadaqah (zakat). Regarding that which belongs to two partners, they can make claims for restitution from each other with equity. An old goat and a defective one are not to be accepted as sadaqah (zakat).” Az-Zuhri said: When the collector comes, the goats will be apportioned into three flocks: one containing bad, the second good, and the third moderate. The collector will take zakat from the moderate. Az-Zuhri did not mention the cows (to be apportioned in three flocks).