The move was made Wednesday.
The NFL announced two weeks ago that Nealy will be suspended for the first four games of the season for violating rules against performance-enhancing drugs. He was a member of the practice squad for six weeks last year.
In a statement distributed by the NFL Players Association after the punishment was revealed, Nealy said he took a supplement with a banned stimulant and that he took responsibility for his action.
Higgins, out of NCAA Division II Nebraska Omaha, played for New Orleans in 2011 and 2012.
The Vikings report to training camp Thursday.
AP NFL website: www.pro32.ap.org and www.twitter.com/AP-NFL