Musannaf Ibn Abi Shayba 18:23

Abu Bakr narrated to us, he said: Muhammad ibn Bakr narrated to us, from Ibn Jurayj, from ‘Amr ibn Shu‘ayb, he said: Abu Bakr said: "Whoever has his blood money (diya) in sheep, then every camel is worth twenty sheep. And whoever has his blood money in cows, then every camel is worth two cows."