Musannaf Ibn Abi Shayba 18:34

Abu Bakr narrated to us, he said: Abu al-Ahwas narrated to us, from Abu Ishaq, from Asim, from Ali, he said: Regarding quasi-intentional homicide: thirty-three hiqqah (four-year-old camels), thirty-three jadha'ah (five-year-old camels), and thirty-four thaniyyah (three-year-old camels). They are all pregnant (khalifah), up to those entering their sixth year (bazil).