Bloodhound/Legends

"Awright, lads. The're past! An' here come the bloodhounds!"

- A Mandalorian slave describes Shrike Squadron

Bloodhounds were creatures which were known to pursue their prey with much ferocity. During the Battle of the City of Bone, the Mandalorian slaves who were revolting referred to Shrike Squadron as "bloodhounds" in an effort to describe their tenacity.

Behind the scenes
Although only receiving one mention in Star Wars 69: Death in the City of Bone, bloodhounds are most likely a type of dog.

In the real world, bloodhounds are a type of hunting dog, which explains the comparison given in the comic.