Primary Industries Minister Nathan Guy says the discovery on a Bay of Plenty farm of the leg of a goat or deer from overseas should never have happened.
The leg was found in a delivery of palm kernel expeller, or PKE.
New Zealand gets nearly all of its PKE from Malaysia and Indonesia and uses it primarily as supplementary feed for dairy cows.
New reports by biosecurity officials have confirmed several flaws in the PKE supply chain in Indonesia and Malaysia.
Mr Guy says he's looking to strengthen PKE import rules, and says he has told a number of foreign PKE processors they have to improve their bird and rodent control.
He says he has also made an urgent change to the Import Health Standard to try and stop PKE coming to New Zealand from unapproved plants.
An investigation of the PKE supply chain in Malaysia by two New Zealand farmers found woeful biosecurity at a PKE processing plant in an area that had recently had a foot-and-mouth outbreak.
One of those farmers, David Clark, says he can't believe the ministry is still allowing PKE in.
The ministry says it doesn't know where the rest of the goat or deer is, and it might introduce a new levy to fund biosecurity inspections in Malaysia and Indonesia.