Free-range egg production may have a greater environmental impact than cage systems

British researchers have found that organic free-range egg farms may place a significantly greater burden on the environment than conventional cage-based poultry systems. The findings were published in the journal Royal Society Open Science.

According to the study, organic free-range egg production generates nearly twice the greenhouse gas emissions per kilogram of eggs compared with conventional cage systems. Researchers attribute this to lower production efficiency, as more hens are required to produce the same amount of eggs, resulting in higher feed consumption. Feed production is the main contributor to the overall environmental footprint.

The study also found that organic free-range systems perform worse in terms of eutrophication potential, environmental acidification and land use. In addition, mortality rates among laying hens were highest in organic free-range farms.

However, one of the study’s authors, Dr Harriet Bartlett, stressed that the findings do not provide a complete assessment of all aspects of poultry production. She noted that organic farming may offer advantages in terms of lower pesticide toxicity and potentially reduced impacts on on-farm biodiversity.

The researchers conclude that, as global egg consumption continues to rise, evaluating housing systems requires a balanced approach that considers not only animal welfare but also climate impacts, natural resource use and other environmental indicators.