'Close to the sheds, the smell is overpowering': inside a UK mega farm

Each shed here contains 42,000 chickens. The conditions are all in line with government regulations, but there are around 17 birds per square metre

In a valley in rural Herefordshire, near the village of Kington, four industrial sheds lie partly covered in trees, with an apple orchard on the approach. From the top of the hill there is no odour, but nearer to the sheds - 100m long by 20m wide, with 42,000 chickens in each - the sweetish, sickly smell is overpowering. The broiler chickens, grown for meat, are stocked at around 17 birds per square metre. Birds are packed as far as the eye can see within the buildings, making it impossible to see the floor.

Related: UK has nearly 800 livestock mega farms, investigation reveals