Slayton didn't practice Thursday due to an illness, Dan Salomone of the Giants' official site reports.
Slayton is making a surprise midweek appearance on the Giants' injury report, making him the second member of the team (running back Gary Brightwell) to come down with an illness this week. While Slayton still has a bit of time to improve ahead of Sunday's game against the Commanders, there's a decent chance he's listed as questionable following Thursday's absence. Friday's report may reveal as much.