The 6-1, 240-pound Ganaway was a sixth-round pick of the Jets and was released on Friday. His senior season at Baylor, Ganaway rushed for 1,547 yards with 21 touchdowns.
Heard, 6-6 and 339 pounds, played for Rams defensive line coach Mike Waufle in Oakland in 2010 after making the team as an undrafted free agent. He made two starts last year for Buffalo.
The Rams drafted Salas in the fourth round in 2011. Murphy was a third-round pick in 2010.and appeared in 14 games as a rookie, but missed the entire 2011 season with an ankle injury.