Thieves killed a puppy as they drove off with 22 pregnant dogs and other puppies.
The raiders drove off with two litters of pups, some just three weeks old, and pregnant adult dogs.
Police said the theft from Jackson Farm in Tarleton, Lancashire, was ‘despicable’ and are appealing for witnesses.
A devastated breeder found the dead pup in the grounds, believed to have been run over as the thieves made their escape.
Sgt Amber Yahchouchi from Ormskirk Police said: ‘This is an absolutely despicable offence undoubtedly motivated by pure greed as the dogs which were stolen were the most valuable breeds.
‘The puppies had already been paid for and reserved, so there will be families and children who will be especially upset.
We’re appealing for information after a number of puppies were stolen in a disgraceful and appalling act of thievery. Sadly a Cockapoo puppy, believed to have been run over by the getaway vehicle, was also found dead on the grounds of the farm.
‘We are really concerned for the welfare of these animals and we don’t know whether they will be looked after properly. It’s important to remember that given their young age and the fact some of the dogs are pregnant, these animals require professional care.
‘If you or someone you know have been offered puppies for sale, even if you have been told they won’t be ready for a few weeks, please let us know.
‘Some of them look very distinctive as they are merle coloured and will be easy to identify.
‘We are also asking people who are part of dog interest groups on social media to please spread the message and report any information about the whereabouts of these animals to us so we can get them back safe and well.’