Three genetically modified cows are dead after being born with with ovaries that grew so large they caused ruptures and killed them.
The animals were being used in a study by the AgResearch centre at Ruakura, Hamilton. AgResearch scientists are seeking human fertility treatments through GM cows' milk.
"(An animal) was found dead in a paddock. It showed no previous exterior symptoms or anything like that, and a few days later a second animal died," says Dr Jimmy Suttie, AgResearch's applied technologies group manager.
A third animal was put down for scientists to study. They are studying its tissue to try to find out what made the ovaries grow to the size of tennis balls rather than the usual thumbnail-size, the Weekend Herald reported today.
The newspaper obtained details of the deaths in an Official Information Act request and says it has reignited debate over the ethics of GM trials on animals.
Suttie says the deaths are not a big deal and told the newspaper they are part of the learning process for scientists.
He says all the right procedures were followed after the deaths - the animal ethics committee was notified and MAF.
But he says it is impossible to say if the animals were in pain.
"The Ethics Committee and the vets have the power to stop any experiment if they see any sign of distress, and at no time did they ask us to do that," he says.
AgResearch has permits to put human genes into goats, sheep and cows for the next 20 years to see if the animals can produce human proteins in their milk, which could be used to treat human disorders in the future.
But the deaths will reignite debate around genetic modification.
GE-Free NZ spokesman Jon Carapiet says details of the calf trial show the animal welfare committee overseeing AgResearch's work is "miles away from the ethics and values of the community".
"The latest story is quite horrifying for most New Zealanders. I guess the question is - when you have very powerful and extreme science practices, we have got to have some ethics. We've got to have some values," he says.
The animals died last year, aged six months.
They were formed when human genetic code injected into a cow cell was added to an egg from a cow's ovary and put into a cow's uterus.
It was part of an experiment to see if the genetic code would enable the cows that were produced to produce milk containing compounds that could be used as a human fertility treatment.
The one cow left is producing human protein as it was meant to and it is being intensively monitored by the research company.
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