It is narrated from Hazrat Salamah (may Allah be pleased with him) that once two sacrificial camels were sent with a man, and he was instructed: If any disease befalls them (and they are near death), then slaughter them and dip their shoes in their blood and mark it on their foreheads, so that it is clear that these are sacrificial animals. And neither you nor any of your companions should eat anything from them; rather, leave it for those who come after.