Book 20, Number 20.27.93:

Yahya related to me from Yahya ibn Said from Muhammad ibn Ibrahim ibn alHarith at-Taymi from Rabia ibn Abi Abdullah ibn alHudayr that he saw Umar ibn al-Khattab taking the ticks off a camel of his at as-Suqya while he was in ihram.

Malik said that he disapproved of that.