A recent "personality test" for cows by AgResearch and DairyNZ may have the answer.
The study, Toward on-farm measurement of personality traits and their relationships to behaviour and productivity of grazing dairy cattle, was published in the Journal of Dairy Science.
There was growing evidence that a farm animal's personality was linked to its productivity, researchers said.
The study found that calmer and more curious cows grazed for longer and researchers concluded this probably contributed to more milk production.
Based on their findings, researchers could suggest which personality test would be the most practical on-farm and this allowed farmers to make tailored plans for managing individual cows.