New Zealand study finds calmer, curious cows yield more milk

Researchers studied 87 pasture-managed dairy cows over 16 days at Lincoln University Research Dairy Farm in Lincoln, New Zealand. The work was carried out from November 11 to 30, 2019, and has been published in the Journal of Dairy Science.

The study examined whether personality characteristics were linked to everyday activities, including grazing and lying, and whether those behaviours were associated with milk output. Each animal completed one standardised behavioural test on five consecutive days.

The tests recorded reactions to a new object, physical restraint, an unfamiliar person, a person approaching within an avoidance-distance test, and the milking process. On the basis of the results, the researchers grouped the cows into three personality categories: “fearful of humans”, “calm and investigative”, and “reactive during milking”.

Cows classified as the most calm and investigative spent approximately 70 minutes more each day grazing than those at the opposite end of the scale. Their additional grazing was not accompanied by a reduction in lying time. The same group produced around 5.5kg more milk per day, while the report said that the longer grazing period was “likely” linked to the higher yield.

Animals that showed greater fear of people, including by maintaining a larger avoidance distance and reacting to humans, had less lying time. Cows that were most reactive during milking tended to produce about 1.8kg less milk per day than other animals.

The researchers wrote that the findings added to existing research showing an association between cattle personality, daily behaviour and productivity. They also said that the brief behavioural tests could be used on commercial farms to identify individual characteristics and help adapt management to the needs of particular cows.