Hadith 5:106
Ali ibn Mushir narrated to us, from al-Ajalh, from al-Sha'bi, who said: The Messenger of Allah (may Allah bless him and grant him peace) wrote to Yemen: "When the camels become numerous, then for every fifty there is a hiqqah (a camel in its fourth year), and for every forty there is a bint labun (a camel in its third year)."
حدثنا علي بن مسهر عن الأجلح عن الشعبي قال كتب رسول الله صلى الله عليه وسلم إلى اليمن إذا كثرت الإبل ففي خمسين حقة وفي كل أربعين بنت لبون