M. bovis – which can cause udder infection abortion, pneumonia and arthritis – was discovered in New Zealand in July 2017.
A year later, Ardern and O'Connor announced the Government was putting aside just under $900 million to eradicate the disease.
Speaking to the Herald, O'Connor said achieving complete eradication would be a "huge step forward in terms of our biosecurity systems".
And it's a step that is receiving a lot of international attention.
"I have spoken to a number of people from Ireland who are envious that their government didn't undertake the same commitment."
According to the Irish Examiner, Ireland's Agriculture Minister Michael Creed said M. bovis was now considered to be endemic in the country's cattle population.
O'Connor said he had been told that Irish officials underestimated the impact of M. Bovis on their farming system.
He hoped New Zealand would be able to share its eradication knowledge with other affected countries so they could embark on the same programme.
O'Connor said the eradication plan had made New Zealand's biosecurity system as a whole more resilient.
He said farmers were now paying more attention to things like washing boots and vehicles.
"While it's been a tough time for the farmers involved, it will ensure that overall we have better biosecurity systems that we will need into the future."
Another highlight for O'Connor was celebrating his 25th anniversary as an MP.
On the morning of the anniversary, he was given a standing ovation by his Labour colleagues as he walked into the caucus room.
He was elected to Parliament in 1993 and has been a minister in the fifth and sixth Labour Governments.
He said they had been "great years".
And how did he celebrate his 25 years as a politician?
"A cup of tea with [Labour MP] Ruth Dyson," who was also celebrating 25 years as an MP.