It is narrated from Hazrat Mu'adh (may Allah be pleased with him) that (if the number of cows is less than thirty, I will not take their zakat until I present myself before the Noble Prophet, peace and blessings be upon him, because) the Noble Prophet, peace and blessings be upon him, did not give me any instruction regarding cows being less than thirty.
Hadith Referenceمسند احمد / مسند الأنصار رضي الله عنهم / 22010
Hadith Gradingحکم دارالسلام:رجاله ثقات، وهذا إسناد منقطع، طاووس لم يدرك معاذا