You can RESEED
Identity Columns of all tables by using sp_MSForEachTable
to loop through all the tables and executing the DBCC CHECKIDENT
command if the specific table has an identity column:
EXEC sp_MSForEachTable '
IF OBJECTPROPERTY(object_id(''?''), ''TableHasIdentity'') = 1
DBCC CHECKIDENT (''?'', RESEED, 0)