The Messenger of Allah ﷺ said, "When one of you sells a sheep or a milch camel, he must not let its milk accumulate in the udder to deceive the buyer."
قال رسول الله ﷺ: إذا باع أحدكم الشاة أو اللقحة فلا يحفلها.
Narrated by Nasai (4486), Ahmad (7699), and Ibn Hibban (4969), from the hadith of Abdul-Razzaq — and it is also in his Musannaf (14864) — Mamar informed us, from Yahya bin Abu Kathir, Abu Kathir informed me, that he heard Abu Hurairah, and he mentioned it. Its chain is sahih."Tahfil" means gathering milk in the udder of the she-camel. "Liqhah" is the she-camel that has recently given birth.