The Bills signed rookie offensive tackle Jamon Meredith off Green Bay's practice squad to bolster their offensive line after Butler sustained a season-ending injury to his right knee. Tight end Jonathan Stupar was promoted from Buffalo's practice squad to fill in for Schouman, who'll also miss the season with a right knee injury.
The changes come as Buffalo (1-1) prepares to host New Orleans (2-0) on Sunday, and after both players were hurt in a 33-20 win against Tampa Bay last weekend.
The decision to place Butler on IR was not a surprise after coach Dick Jauron said Monday that the player would require season-ending knee surgery. Butler was hurt late in the second quarter when Buccaneers defensive lineman Stylez White rolled into the back of Butler's legs while attempting to strip the ball from quarterback Trent Edwards.
Schouman was carted off the field late in the third quarter after twisting his knee while being tackled after making a 6-yard catch. He led the Bills with 62 yards receiving against Tampa Bay, and ranks second on the team with nine catches for 103 yards in two games this season.
The Bills tight end ranks could be further depleted because rookie Shawn Nelson's status is uncertain after he strained his shoulder last weekend. Stupar, who spent most of last season on Buffalo's practice squad, had a solid preseason but failed to make the Bills roster after the team made its final cuts.
Meredith was drafted in the fifth round by the Packers, but failed to make Green Bay's roster. Listed at 6-foot-5 and 304 pounds, Meredith had 29 starts at South Carolina.
The Bills made two other practice squad moves, releasing linebacker Alvin Bowen and signing rookie linebacker Marcus Freeman, who was drafted in the fifth round by Chicago.
Bowen was selected by Buffalo in the fifth round of the 2008, but missed his entire rookie season after hurting his knee in training camp.