Narrated Abdullah ibn Saad al-Ansari: I asked the Messenger of Allah ﷺ as to what makes it necessary to take a bath and about the (prostatic) fluid that flows after taking a bath. He replied: that is called madhi (prostatic fluid). It flows from every male. You should wash your private parts and testicles because of it and perform ablution as you do for prayer.
Hadith Referenceسنن ابي داود / كتاب الطهارة / 211
Hadith Gradingالألبانی:صحيح | زبیر علی زئی:إسناده حسن
Hadith Takhrij« تفرد بہ أبو داود، (تحفة الأشراف: 5328)، وقد أخرجہ: سنن الترمذی/الطھارة 100 (133)، سنن ابن ماجہ/الطھارة 130 (651)، مسند احمد (4/342، 5/293) (صحیح) »