Image copyright Dyfed-Powys Police Image caption An investigation started after a farmer reported the theft of one of his 300 cows

A police force says it has become the first in the UK to use DNA evidence from a stolen cow in a criminal case.

Dyfed-Powys Police used DNA from a heifer, which had been retagged by a neighbouring farmer after escaping from a field, to prove it had been stolen.

The blood samples were compared against cows on the victim's farm to prove a familial link.

David Aeron Owens, of St Clears, pleaded guilty to theft at Swansea Crown Court on Monday.

In 2017 the force also became the first force in Wales to use DNA evidence to secure a conviction against a man for handling stolen sheep.

The force said the investigation started in December 2017, when a farmer reported the theft of one of his 300 cows which had escaped from his field four months earlier.

Owens had denied the missing animal was on his land, but the victim recognised it among the herd.

PC Gareth Jones visited the farm and was shown a cow passport, listing ear tag numbers for the cow in question and the animal Owens alleged was its mother.

The stolen cow, which was separated from the herd, had blood samples taken for DNA comparison.

'Long and protracted inquiry'

"It was established through DNA tests that the heifer listed on the cow passport was not related to the disputed cow," PC Jones said.

Further samples were taken by a vet which were compared with a cow on the victim's farm.

They were proven to be siblings, and based on the DNA results, charges were brought against Owens.

He was sentenced to a £4,000 fine and £500 costs.

PC Jones added: "This has been a long and protracted inquiry, and it has taken a lot of work and patience to get to this point.

"Without the use of the heifer's DNA we would not have been able to prove that it had been stolen by Mr Owens, and that he had tried to alter identification tags to evade prosecution."