قال النبي ﷺ ليس على المسلم في فَرَسه وغلامه صدقةٌ
صحيح البخاري كتاب الزكاة
The Prophet (SAW) said: A Muslim is not obliged to give charity for a horse of his or a servant boy of his.
Sahih Al-Bukhari, The book of zakat