New study into judgement bias investigates whether optimistic judgements are linked with access to pasture for dairy cows.
While much has been made of the human cost of lockdown, new research attempts to shed some light on whether dairy cows experience the same kind of emotional fatigue when deprived of access to pasture.
A new study from Queens University Belfast (QUB) and the Agri-Food and Biosciences Institute seeks to explore the idea of ‘Livestock Lockdown’ and the potential parallels between the kind feelings experienced by humans during the pandemic and those of twenty-nine Holstein Friesian counterparts when subjected to 18 days of overnight pastures and 18 days being kept indoors full-time.
According to the reports authors, positive emotions are linked to optimistic judgements and outcomes when presented with ‘ambiguous stimuli’. However, the reverse is also true with those who are anxious or suffering from depression more likely to pursue pessimistic lines of thinking.
With this in mind, researchers attempted to assess the emotional state of the dairy cattle by testing them in an attempt to ascertain whether cows, like humans, have a judgement bias that which can be used to determine their psychological wellbeing and mood.
To do this each cow was trained to approach a food rewarded bucket location, but not approach another, unrewarded bucket location.
After learning this task, to test judgement bias, the researchers presented cows with buckets in between the trained locations. Approaching these intermediate buckets would reflect an expectation of reward under ambiguity – an 'optimistic' judgement bias, suggesting positive emotional states.
Interestingly, the researchers found that cows kept indoors full-time were faster to approach the known rewarded bucket location.
According to Dr. Gareth Arnott, a senior lecturer in Animal Behaviour and Welfare at Queen’s University and principal investigator on the research, scientists and dairy consumers have long been concerned by the effects of depriving dairy cattle of access to pasture.
“Pasture access can promote natural behaviour, improve cows’ health, and cows given the choice spend most of their time outside,” he explains. "However, the effects of pasture access on dairy cows’ psychological wellbeing have been poorly understood – that is what our judgement bias study intended to measure.”
The research, which has been published in the nature journal Scientific Reports, suggests consumers overwhelmingly support pasture-based systems for dairy cattle.
According to figures, more than 95% of the British public believe pasture access benefits dairy cows, with data from Germany, the United States and Canada, and Brazil confirming that stance with 88%, 84% and 81% respectively.
But while many industry stakeholders also value pasture access, there is an increasing trend for farmers across Europe and North America to keep cattle indoors all round.
Even so, 95% of British and Irish dairy cows went out to pasture in 2019 and in New Zealand there is a feeling that allowing cows to express their natural behaviour can not only be beneficial in terms of emotional wellbeing, but also help with carbon footprints.
Speaking to Farmers Weekly, Helen Thoday, senior manager for DairyNZ, explained that the wide-open spaces of New Zealand enabled cows to socialise freely and within natural sub-groups found in cow herds.
Thoday also believes that cows being able to rest in comfort and having the choice of being able to go indoors, if a barn or covered feedpad is available, provide other further benefits.
“It’s kind of like everyone’s winning when we focus on grass production, having cows outside on grass is just a triple win for the consumer, the cows and the carbon footprint,” she added.
The report findings echo this sentiment, with the authors concluding that access to dairy pasture induced more positive emotional states with cows exhibiting longer lying times, less restlessness, and greater herd synchrony.