the Prophet forbade the price of cats and dogs, except hunting. (Da if) Abu Abdur-Rahman (An-Nasa I) said: The Hadith of Hajjaj from Hammad bin Salamah is not authentic:
Sunan an-Nasa'i Book 42, Hadith 33
← Previous Hadith "The Messenger of Allah said: 'The worst of earnings arte the gift of a female fornicator, the price of a dog and the earnings of a cupper.""

Sunan an-Nasa'i Book 42, Hadith 32 Next Hadith → a man came to the Prophet and said: "O Messenger of Allah, I have trained dogs; advise me concerning them." He said: "Whatever your dogs catch for you, eat," I side: "Even if they kill it?" He said: "Even if they kill it. " He said: "Advise me about my bow. "He said: "Whatever your arrow returns to you, eat." He said: "Even if it gets away from you, so long as you do not find the mark of an arrow other than yours on it, or you find that it has gone rotten."(Another chain).

Sunan an-Nasa'i Book 42, Hadith 34