Factory farming could soon enter a new era of mass production. Companies in the US are developing the technology needed to 鈥渃lone鈥� chickens on a massive scale.
Once a chicken with desirable traits has been bred or genetically engineered, tens of thousands of eggs, which will hatch into identical copies, could roll off the production lines every hour.
Billions of clones could be produced each year to supply chicken farms with birds that all grow at the same rate, have the same amount of meat and taste the same.
Advertisement
This, at least, is the vision of the US鈥檚 National Institute of Science and Technology, which has given Origen Therapeutics of Burlingame, California, and Embrex of North Carolina $4.7 million to help fund research. The prospect has alarmed animal welfare groups, who fear it could increase the suffering of farm birds.
Disease-resistant
That is unlikely to put off the poultry industry, however, which wants disease-resistant birds that grow faster on less food. 鈥淧roducers would like the same meat quantity but to use reduced inputs to get there,鈥� says Mike Fitzgerald of Origen.
Normal cloning does not work in birds because eggs cannot be removed and implanted. Instead, the company is trying to bulk-grow embryonic stem cells taken from fertilised eggs as soon as they鈥檙e laid. 鈥淭he trick is to culture the cells without them starting to differentiate, so they remain pluripotent,鈥� says Fitzgerald.
Using a long-established technique, these donor cells will then be injected into the embryo of a freshly laid, fertilised recipient egg, forming a chick that is a 鈥渃himera鈥�.
Strictly speaking a chimera isn鈥檛 a clone, because it contains cells from both donor and recipient. But Fitzgerald says it will be enough if, say, 95 per cent of a chicken鈥檚 body develops from donor cells. 鈥淚n the poultry world, it doesn鈥檛 matter if it鈥檚 not 100 per cent,鈥� he says.
Genetic modification
With its patent still at application stage, Origen is unwilling to reveal if it can reliably obtain such chimeras. But it has occasionally created the ideal: chicks that are 100 per cent donor-derived, or pure clones.
Another challenge is to scale up production. To do this, Origen has teamed up with Embrex, which produces machines that can inject vaccines into up to 50,000 eggs an hour.
Animal welfare groups say that it would be cruel if breeders used the technology to mass-produce the fastest-growing birds. Some birds already go lame when bone growth doesn鈥檛 keep pace with muscle growth.
鈥淭he last thing they should be doing is increasing growth rates,鈥� says Abigail Hall of Britain鈥檚 Royal Society for the Prevention of Cruelty to Animals.