A legal challenge over the use of fast-growing broiler chickens will return to court later this month after a previous attempt failed.
The judicial review at the Court of Appeal will take place on 23-24 October, according to Humane League UK, which spearheaded the last attempt.
The charity argues that the use of conventional meat chicken breeds which 'grow unnaturally large and unnaturally fast' breaches welfare regulations.
Campaigners also argue that Defra has 'an unlawful policy' which permits the use of so-called 'frankenchickens' in farming.
Humane League UK lost its initial case in the High Court in May last year, with Judge Sir Ross Cranston ruling that Defra's policies were not unlawful.
But campaigners continue to point to the law, which they say states that animals cannot be farmed if it is likely their genetics cause health and welfare problems.
Kate Parkes, a specialist at the RSPCA, which will be providing evidence at the judicial review, said the scale of the suffering involved with meat chickens was 'huge'.
She said: "We are talking nearly a billion chickens every single year who live short, brutal lives with serious health and welfare issues which could so easily be avoided.
“It's really important to stress that slower-growing breeds, with significantly better health and welfare, are already available and commercially viable.
Ms Parkes explained that fast-growing chickens reach the average UK slaughter weight in just 35 days after hatching.
"Shockingly, a standard supermarket chicken grows so fast that if we were to genetically breed humans in the same way, it would be the equivalent of a morbidly obese 28 stone three-year-old."
Concerns about meat chicken breeds have been frequently highlighted by animal welfare groups, as they say such breeds have been genetically selected to grow so fast that they suffer from health issues.
According to research by animal welfare organisations, faster-growing breeds are more likely to die or need to be culled due to ill health.
Animal charities have also been campaigning for food companies to commit to ending the use of fast-growing broilers by asking them to sign up to the Better Chicken Commitment.
This urges firms to opt for slower growing poultry breeds. KFC, Nando’s, Greggs, Marks and Spencer and Waitrose are among the 330 companies in the UK and EU to have committed.
