Musannaf Ibn Abi Shaybah

Hazrat Abu Nadrah (may Allah have mercy on him) says that I asked Hazrat Ibn Umar (may Allah be pleased with them both) that our rulers prohibit us from conducting Salam transactions in animals. He (may Allah be pleased with him) replied, "Then if your rulers prohibit you from this, obey them." And at that time, their rulers were personalities like Hazrat Hakam Ghafari and Hazrat Abdur Rahman bin Samurah (may Allah have mercy on them).