Is 3-in-2 milking worth adopting?

1 July 2019

A new levy-funded research project will explore the benefits to farmers and cows of milking three times in two days.

Milking frequency is one way farmers are choosing to evolve, which is why DairyNZ has this month started research into the human, animal and production response of milking three times in two days (3-in-2). Flexible Milking for Healthier People and Cows is a three-year project, led by DairyNZ and funded by $499,536 from the Sustainable Farming Fund and $306,914 from the DairyNZ levy.

Project goals

  • Farmers and advisers will have the confidence to adopt, optimise, and support the use of 3-in-2 milking.
  • Enhanced wellbeing (less hours spent working on farm and greater flexibility).
  • Increased economic sustainability of farming businesses using 3-in-2 milking (through people and cow health).

Year one

The first year of the study will focus on learning from farmers already using 3-in-2 strategically. This will help guide development of resources and information. A farmlet trial will also be set up at Lincoln University Research Farm. Four milking frequency scenarios will be tested:

  • Full season twice-a-day (TAD) (the baseline for comparison, i.e. ‘control’ scenario).
  • 3-in-2 from March.
  • 3-in-2 from December.
  • Full season 3-in-2.

The impact on milk production, body condition, animal behaviour, pasture production and grazing management will be measured.

Year two

The project will expand to piloting 3-in-2 on commercial farms, including measures to evaluate the effects on people of moving to a 3-in-2 system. A second trial will be conducted to investigate different intervals used with 3-in-2.

For example, 3-in-2 started as milking every 16 hours (16-16-16), but this has a night milking associated with it. It then evolved to 14-16-18 and now to 12-18-18 (which will be tested in the farmlets).

The second trial will also look at whether 10-19-19 can be used successfully (or if milking gaps could be extended to 21-hour intervals). This would enable two milkings to be completed on Monday, Wednesday and Friday, with one milking each on Tuesday, Thursday, Saturday and Sunday.

Year three

The focus in this stage will be on modelling to predict outcomes in different flexible milking scenarios. For example, if a farmer wanted to go once-a-day (OAD) milking during calving (to reduce work at a busy time); then go TAD through peak lactation; then 3-in-2 through mid-lactation; and OAD near dry-off.

Dairy farmers will be given results from the project regularly and resources will be developed to help farmers make informed decisions regarding the use of 3-in-2 milking.

Learn more about this project at and about OAD milking at

This article was originally published in Inside Dairy July 2019

Media inquiries:

Lee Cowan

Senior Engagement & Communications Manager

Phone 021 930 836

Vanessa Feaver

Senior Communications & Media Specialist

Phone 027 836 6295

Photo usage: If you require high-resolution versions of photos featured in this article, please contact