One of Sydney's highest-profile racehorse breeders - Bob Ruttley - has been given the largest fine in NSW for breaching heavy vehicle laws while operating his trucking company Ruttley Freightlines.

He pleaded guilty to 84 breaches of new ''chain of responsibility'' laws for overweight or oversize trucks.

Other companies owned by him will also be prosecuted in South Australia for other breaches.

He is in the process of liquidating six companies with debts of more than $33.6 million - including $3 million in NSW payroll tax, and $13.3 million in group tax.

The Sydney Herald has uncovered Ruttley Freightlines to be a rogue trucking operation which was partly financed by avoiding paying taxes and failing to pay employees super annuation.