Study finds chicks experience positive emotions when handled gently by humans
Research has been carried out at Bristol University
Chicks experience positive emotions when handled gently by humans, according to a study from the University of Bristol.
Researchers at Bristol Veterinary School trained 20 domestic chicks from a laying hen strain in a two-chamber set up, one orange and one blue.
One of the chambers featured gentle human handling, slow stroking and soft speech, while the other had humans who were still and silent.
The chicks consistently spent more time in the chamber associated with gentle human handling, demonstrating a positive association with the experience.
They did not avoid the chamber linked to a neutral human presence, suggesting an attraction to the gentle-handling environment.
Over the study, the chicks increased their acceptance of gentle handling and many fell asleep in the hands of the humans who were stroking them.
Dr Ben Lecorps, senior lecturer at Bristol Veterinary School, was the principal investigator on the study which is published in the journal Animal Welfare.
“Our findings show that gentle human contact can trigger positive emotions in young chicks,” Dr Lecorps said.
“The study demonstrates how simple, calm handling has the potential to shape the human-animal relationship from fear-inducing to positive and consequently improve the chicks’ welfare.”
Researchers say interaction with humans in early life is known to influence animal behaviour, stress responses and welfare.
However, until this study it was unclear whether animals perceive gentle handing as emotionally positive.
The team used a conditioned place preference paradigm, widely used in affective neuroscience, to assess this.
This method is used to explore what animals remember of past experiences, with the principle that animals should develop a learnt preference for places where they felt good.
During the study, the chicks spent five minutes in a chamber with either soft stroking and calm talking, or humans remaining static and silent.
They were given six sessions of each treatment across 12 days, with their preferences assessed over three consecutive days.
Chicks consistently spent more time in the chamber associated with gentle handling but did not show an aversion to the neutral chamber.
The researcher wrote: “These results indicate that gentle human contact acquired positive associative value rather than merely reducing aversion.
“These findings provide experimental evidence that human-animal interactions can function as rewarding stimuli in poultry, which has implications for husbandry practices and welfare assessment frameworks.”
The study, titled Gentle human interactions trigger positive emotions in chicks, is published in Animal Welfare.