use strict;
use warnings;

use Data::Dumper;

my $app_text =
   qq{one:partridge\ntwo:\nturtle doves\nthree:french hens\n};

my %fvPairs =
   map { split m{:\n?} }
   map { split m{(?<!:)\n} }
   $app_text;

print Data::Dumper->Dumpxs( [ \ %fvPairs], [ q{*fvPairs} ] );