Published 04/10/2012
A genetically modified cloned calf, who can produce milk without the protein that is thought to cause allergies in infants, has been produced by scientists in New Zealand. The calf was given large doses of hormones at just 7 months of age in order to induce her to produce milk. (Normally, milk is only produced when a cow has her first calf at around 2-3 years old.)
The beta - lactoglobulin (BLG) protein is found in cow's milk but is not present in human milk. This protein is reported to be responsible for an allergy that affects 2-7% of infants under the age of one in the UK. Most will grow out of the allergy by the age of five.
Scientists at AgResearch in Hamilton took cow skin cells and genetically modified them to produce molecules that block the manufacturing of the BLG protein.
The nuclei of these cells were then transferred into cows' eggs from which the nucleus had been removed. Fifty-seven cloned embryos were then implanted into the wombs of surrogate cows. There were five resulting viable pregnancies, one was aborted for cell collection, and one resulted in the live birth of Daisy.
As the clone, known as Daisy, was only born 11 months ago by caesarean, she is too immature to have had a calf herself and produce milk naturally. She was therefore given hormones to induce premature milk production. Compassion is concerned at the distress this hormonal flood may have had on Daisy's wellbeing.
Peter Stevenson, Chief Policy Advisor, Compassion in World Farming, says:
"There is substantial scientific evidence to demonstrate that genetic engineering and cloning all too often results in suffering for both the genetically engineered animal and their surrogate mother.
"It is hard to understand why numerous animals have been subjected to experimentation and stressful conditions in order to produce one calf which may or may not be able to produce offspring with the potential to produce BLG-free milk, which in turn may or may not be palatable to infants with a temporary milk allergy.
"The fact that technology already exists to produce hypoallergenic infant formula from cows milk in an industrial process makes this research seem particularly pointless."
It is concerning that Daisy was born without a tail, as this abnormality is extremely rare in cows. AgReasearch have admitted that they have yet to discover the cause of the deformity.
The European Food Safety Authority (EFSA) has highlighted that cloning results in serious health and welfare problems for both cloned animals and their surrogate mothers.
The low efficiency of the cloning process, with many foetuses dying during pregnancy and many of those that survive dying in the early days and weeks of life, inevitably means a high number of animals are used and many may experience low welfare.
What is known is that pregnancies involving a cloned offspring are often abnormal or difficult, and with the additional risk of a larger than normal calf, often means a caesarean is necessary, which was performed in this experiment. A significantly high proportion of cloned animals die shortly after birth or in the first few weeks of their lives due to conditions such as cardiovascular failure, respiratory problems or immune system deficiencies.
Peter Stevenson adds: "In conclusion, genetic engineering and cloning are inhumane processes that often lead to physical defects and ill-health for the genetically engineered and cloned animals as well as difficult pregnancies and births for the surrogate mothers which may cause significant pain and distress."