Researchers from the University of Bristol's School of Veterinary Sciences have concluded that the wellbeing of barn chickens is increased if they have activity objects, perches and other stimulation.
Around 75 per cent of barn chickens reared for UK households are in barns which don't have natural daylight or activity objects such as pecking blocks .
The study, one of the first of its kind in the UK , looked at the behaviour of birds to find out how content they really were in different conditions.
The aim of the research, funded by Morrisons, was to find out which measures made a genuine difference to the welfare of chickens.
A total of 120,000 birds were observed from birth to determine whether the chickens appeared to be positively occupied, bored, calm, depressed, tense or content, among other measures.
The study found that the chickens were more confident and active in an enriched environment and confirmed that the birds have a greater wellbeing with activity objects, perches and daylight.
Morrisons has therefore decided to move all its standard fresh chickens to the enriched regime and all their chicken will be able to live in barns containing windows, perches, straw bales and pecker blocks - allowing the chickens to express their natural behaviour.
Two researchers spent a total of more than 100 hours over the course of a month watching birds in four houses and measuring their wellbeing based on a number of different indicators.
Dr Claire Weeks, Senior Research Fellow in Animal Welfare at the University of Bristol's School of Veterinary Sciences, said: "Despite the high levels of public interest in chicken welfare, to date there has been relatively little research into the impact that environmental enrichment can have on their behaviour.
"This study, which analysed the behaviour of over 120,000 birds, has shown it does make a positive difference. By acting on the findings Morrisons is helping drive up welfare standards for a substantial section of the British chicken flock."
Louise Welsh, Agriculture Manager at Morrisons, said: "We are aware that many customers are concerned about the conditions that chickens live in but can't afford to buy free range or even organic meat. That's why we have made the move to ensure that all of our standard chickens will enjoy higher welfare living conditions.
"Our standard range accounts for over 90 per cent of all Morrisons' sales of chicken. That means over a million chickens a week will now be raised in better conditions, proven to have a positive impact on their wellbeing."
Mia Fernyhough, UK Food Business Manager at Compassion in World Farming, said: It is great to see that Morrisons is considering the welfare of its meat chickens and taking the first steps to improve their living conditions.
Compassion in World Farming works closely with many organisations within the food industry, including the supermarkets, encouraging progress and creating a better future for chickens and other farm animals. We will continue to work with Morrisons to help further the welfare of the animals used in their meat and dairy produce.
David Gibson, Director of Agriculture, Moy Park, said: All chickens produced for Morrisons are grown in sheds with windows, allowing natural light into the houses. The study reinforces what we have seen in our farms - that this source of natural light has a very positive effect on the chickens making them more active.
As pointed to in the research study, we also enrich the chicken houses, which further enhances the environment for the birds and allows them to express their natural behaviour.
Explore further: Purring tempo, sliding notes grab cats' attention