The dogs, many of which were in poor physical condition, are now in the care of the DSPCA.
26 puppies and seven adult dogs were seized at Dublin Port on Sunday, following the search of two vehicles.
After Gardaí expressed concern with the manner in which the dogs were being transported, drivers of the vehicles were unable to produce any proof of ownership, pet passports or vaccination/microchip certificates.
The dogs are now in the care of the DSPCA and have gone through extensive health checks.
Included in the seizure are two litters of very young puppies, about two weeks of age, travelling with their mothers.
One of the other female dogs is heavily pregnant.
Some of the animals are infested with fleas, some are of a poor body weight and one of the puppies has an infected umbilical cord.
There are also concerns that some of the Jack Russell puppies have had their tails docked.
Gardaí have said that investigations are ongoing.
The DSPCA have thanked the Gardaí at Dublin Port for their diligence and would like to remind the public that they are still working to care for animals in these difficult times.
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