All fixed odds racing bets are subject to deductions. They occur due to scratchings and are applied as a deduction of cents in the dollar (effectively, a percentage) from your potential payout.
The calculation is expected payout x (100 - deduction) / 100. So if you bet $10 on a horse to win at $7.00 but suffered 15c deductions, the calculation would be:
$70 x (100-15) /100 = $59.50
You can view scratchings and deduction amounts from the individual race page and the full deductions table is contained at clause 8 of our our Betting Rules here (link)