Rather than messing around with pipes, why not just capture the file to a scalar:

open RES, 'bas.txt';
my $msg; do { local $/; $msg = <RES> };
close RES;
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...then just send that.

 my %mail = ( To      => 'toemailhere',
                     From    => 'fromemailhere',
                     Subject => "Output",
                     Message => $msg
                       );
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_______________
DamnDirtyApe

Those who know that they are profound strive for clarity. Those who
would like to seem profound to the crowd strive for obscurity.
            --Friedrich Nietzsche