All three are expected to be ready for training camp in September.
According to Predators beat reporter Josh Cooper of The Tennessean, general manager David Poile said Gaustad and Wilson each require shoulder surgery that is expected to sideline them for four months.
Bourque has been sidelined with what's reported as a knee injury.
Nashville entered Thursday with the NHL's 29th-ranked offense at 2.29 goals per game and sits 13th in the Western Conference, five points behind the Detroit Red Wings for a berth in the Stanley Cup Playoffs.
I don't know the room very well yet. I don't know how we're going to react in certain situations. We've had a couple of minor tests throughout the [preseason] ... We'll get to know each other as the year goes on. We'll figure it out.
— Oilers coach Todd McLellan on starting the 2015-16 season without a captain
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