DNA tests after 34 puppies were stolen in Carmarthenshire led police to a next-door neighbour, a court has heard.
The West Highland terriers were stolen from a shed at breeder Gwilym Williams's home last October.
Rachel Thomas, 24, of Tregynnor, was caught when officers used DNA to prove her six dogs were from the same litters as the stolen pups.
Thomas was ordered to pay £1,050 compensation and return the dogs by Swansea Crown Court.
The court heard the pups, which were due to go to families who had paid £175 for them, were taken from the shed at Mr Williams' home in Llanfihangel ar Arth.
He called in police to investigate after he suspected Thomas was setting up a rival breeding firm next door.
Dyfed Powys Police seized six dogs from her home and tests proved they were part of the same litter as the 34 taken from Mr Williams' home.
Thomas had denied handling stolen goods but was found guilty following a trial earlier this year.
She claimed she had suffered a "nervous breakdown" and her dog breeding business has since closed.
Thomas, who has since moved from Llanfihangel ar Arth, was also given a two-year conditional discharge by the court.