Bull semen importation into Jersey 'is regrettable'
Some calves born using the imported semen have been put down
Importing non-pedigree bull semen into Jersey despite rules restricting it "is regrettable", the organisation that warned of the error has said.
Semen brought into the island must come from a bull with at least seven "pedigree generations" behind it to maintain the purity of the Jersey herd.
But the American Jersey Cattle Association found non-pure frozen semen from an American bull had been sent.
Until 2008 there had been a complete ban on semen importation into Jersey.
But politicians voted to partly lift the 200-year-old restrictions with conditions about the ancestors of the bulls.
Erick Metzger, the herd services manager at the American Jersey Cattle Association, told BBC Jersey: "Jersey breeders and the Jersey society will be the customers and they'll decide what they want to purchase or what they don't want to purchase.
"Certainly it is regrettable that this happened, but without recent advancements in technology we still wouldn't know that we had a problem.
"It's been a learning experience for us and we think it's something that's going to help us to develop even better genetics down the road as we go forward."
Thirteen calves have been born in Jersey using the non-pedigree semen. Some have already been put down.
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