Running back Adrian Peterson (sprained right ankle) and quarterback Brett Favre were among five Vikings players who did not practice Wednesday as the team began preparations for Sunday's game against Buffalo.

Favre continued to be listed with ankle and right shoulder issues and also has had a neck problem added to the report. Peterson was not on the field during the first portion of practice that is open to the media -- he likely was receiving treatment on the ankle -- but Favre was on the field wearing a baseball cap.

At one point, it appeared Favre was even giving some advice to Sidney Rice as the wide receiver ran routes.

Wide receiver Percy Harvin, meanwhile, was limited because he did not feel well. He was listed as having an illness, which in the past has been code for the fact Harvin is dealing with a migraine headache. However, the fact Harvin did any work at all might be a sign he really has some type of bug.

Also sitting out for the Vikings on Wednesday were defensive end Ray Edwards (right ankle sprain); left guard Steve Hutchinson (thumb); and wide receiver Greg Lewis (concussion).

In addition to Harvin, safety Husain Abdullah (ankle); cornerback Chris Cook (knee); Rice (hip); and safety Jamarca Sanford (hamstring) were limited.

Wide receiver Bernard Berrian (groin) and safety Eric Frampton (hamstring) were listed on the injury report but were able to participate fully in practice.

The Bills, meanwhile, had six starters sit out of practice on Wednesday.

The list included right guard Eric Wood (ankle), left tackle Demetrius Bell (knee), cornerback Terrence McGee (knee); linebackers Chris Kelsay (illness) and Reggie Torbor (shoulder); and defensive end Dwan Edwards (hamstring).

Also unable to practice were tight end Shawn Nelson (illness) and nose tackle Torell Troup (fibula). Running back C.J. Spiller (hamstring) and defensive end Spencer Johnson (hamstring) were limited.