ANIMAL welfare campaigners have won their right to appeal against a High Court decision that deemed the government acted lawfully in allowing the use of fast-growing broiler chickens.

In May, the High Court rejected Humane League UK's legal challenge, which saw Judge Sir Ross Cranston ruling that Defra's policies, which allow the rearing of such chickens, were not unlawful.

Now Lord Justice William Davis, when granting the appeal, said “There is a legitimate argument to the contrary [of the High Court decision] which needs to be considered by the court”.

Humane League UK argues that the use of these meat chicken breeds which 'grow unnaturally large, unnaturally fast' breaches animal welfare regulations.

The so-called 'Frankenchickens' reach their slaughter weight of 2.2kg in 34 to 36 days.

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.

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According to research by animal welfare organisations, faster-growing breeds are more likely to die or need to be culled due to ill health.

Rapid growth rates can contribute to other health problems such as heart failure and sudden death syndrome, whilst other research has shown that around 30% are likely to experience pain from leg and foot issues.

Managing director of the Humane League UK, Sean Gifford, welcomed the news, saying: “The court only grants an appeal if there is a very real prospect of success, and we are thrilled our legal challenge will have this final day in court.

"Fast-growing Frankenchickens, whose short lives are plagued by illness, suffering, and despair, have been let down by the law.

"While the government has abandoned almost every single one of its animal welfare pledges, this appeal, if successful, could legally force them to end the greatest animal welfare crisis of our time."

Managing director of Advocates for Animals and solicitor for the Humane League UK in the case, Edie Bowles, added: “We are delighted that this highly significant case has been granted permission to appeal.

"The judge recognised that the interpretation of this law carries immense significance."