The Prophet's ﷺ zakat collector came to us. I took his hand and read what was written in his instructions, "Do not combine separate flocks, nor separate combined ones, out of fear of zakat." He did not mention a suckling lamb.
حدثنا محمد بن الصباح البزاز حدثنا شريك عن عثمان بن أبي زرعة عن أبي ليلى الكندي
أتانا مصدق النبي ﷺ فأخذت بيده وقرأت في عهده لا يجمع بين مفترق ولا يفرق بين مجتمع خشية الصدقة ولم يذكر راضع لبن
Its isnad is daif. Ibn Majah narrated it in the chapter on zakat, section on what the zakat collector takes from camels, hadith no. 1801, from the hadith of Sharik the judge, through this route. He is a mudallis and used the term "an" [without stating direct hearing]. See the previous hadith.