The win keeps the Terriers flying high at the top of League One and root Mk Dons firmly to the bottom of the division.
"I have kept saying we will beat a team by a big margin - it could have been five or six by half-time," said Jackson.
"That's three wins on the trot and no goals against, so it's been an excellent week for us - and scoring five is good for our goal difference.
"We are not concentrating on anyone else - all we can do is keep picking up points like we are doing."