The Messenger of Allah ﷺ forbade the earnings of the cupper, the earnings of the prostitute, the price of a dog, and the stud fee for a male animal's mating.
نهي رسول الله ﷺ عن كسب الحجام، وكسب البغي، وثمن الكلب، وعسب الفحل.
Nasai (4673) and Ahmad (7976) both narrated it through Muhammad bin Jafar, who said, Shuba narrated to us, from Mughira (that is, Ibn Miqsam Dabbi), who said, I heard Abdul-Rahman bin Abu Naim say, I heard Abu Hurairah say, and then he related it. The wording given here is Ahmad's. Nasai did not mention "the earnings of prostitution."Its isnad is hasan, on account of Abdul-Rahman bin Abu Naim (with a damma on the noon, and a sukoon on the unpointed letter). Ibn Main declared him daif, while Nasai, Ibn Hibban, and Ibn Saad affirmed his reliability, and his hadith is hasan.Ibn Hibban said, "He was among the worshippers of the people of Kufa, one of those who endured continual hunger."Ahmad, at the end of the hadith, mentioned Abu Hurairah's statement, "And the stud fee of a stallion." He said, Abu Hurairah said, "This is from my own purse."Many scholars have found this statement of his problematic, given that it has been established from him as a raised (marfu) narration in another version. Perhaps he initially used to add this to the hadith as he understood it, by analogy with the earnings of prostitution, then he came across the narrations of some of the companions, retracted his statement, and narrated it as a raised hadith.