The Messenger of Allah ﷺ said, "Indeed, the blood-money for one killed by mistake resembling intentional killing, such as one struck with a whip or a stick, is one hundred camels, forty of which must be pregnant."
أخبرني يحيى بن حبيب بن عربي قال أنبأنا حماد عن خالد يعني الحذاء عن القاسم بن ربيعة عن عقبة بن أوس
أن رسول الله ﷺ قال ألا وإن قتيل الخطإ شبه العمد ما كان بالسوط والعصا مائة من الإبل أربعون في بطونها أولادها
Its isnad is sahih. Abu Dawud narrated it in the Book of Diyat, chapter on the diyah for accidental killing resembling intentional killing, hadith no. 4547, from the hadith of Hammad bin Zayd, by this route. It is also found in al-Kubra, hadith no. 6996, and Ibn Hibban declared it sahih, hadith no. 1526, as did Ibn Jarud, hadith no. 773, and others besides them.