The 20-page complaint filed by state authorities earlier this month in Superior Court in Salem County alleges that at least four times from November 2012 to January 2013, Durkin charged between $300 and $450 for sick puppies.
"Families who bring a new puppy into their home will bond with that pet very quickly," acting Attorney General John J. Hoffman said in a statement issued Thursday.
"Those who purchased sick puppies from this defendant - including the family that had to have its new pet euthanized - suffered on behalf of their animals and because of the defendant's alleged failure to disclose health information or provide reimbursement for purchase and veterinary costs. We are pursuing full restitution for those consumers," Hoffman said.
Viking, the Yorkshire terrier-poodle that had been purchased Dec. 19, 2012, as a Christmas gift for a Middlesex County family, became ill within five days, suffering from hypoglycemia, diarrhea, and anemia, according to the suit.
Viking was "nearly comatose upon his arrival at a veterinary clinic" on Christmas Eve, said the suit, noting that on Dec. 27 the new owners "elected to euthanize the extremely ill puppy."
In November 2012, a Gloucester County family bought a Jack Russell puppy that developed a severe cough four days after purchase. A vet later diagnosed and treated the puppy for bacterial broncho-pneumonia, according to the lawsuit.
In January 2013, a Cavalier King Charles puppy bought by a Camden County family was brought to the vet the next day and was found to have ear mites, a yeast infection of the ears, giardia - a parasite that invades the small intestines - and an upper respiratory infection, according to the lawsuit.
Also in January 2013, a Maltese-poodle mix in Hudson County bought from Prada was taken to a vet because he was vomiting, had diarrhea, and was persistently shaking his head because of parasites and ear mites, the lawsuit alleges.
State authorities alleged that Durkin failed to have pets examined by a New Jersey-licensed veterinarian at least three days prior to sale, as required by law, and on various occasions she also vaccinated or inoculated pets herself, without the order of a state-licensed veterinarian.
The state is seeking full consumer restitution as well as civil penalties and reimbursement of the state's investigative costs and attorneys fees.
"Failure to follow New Jersey's laws requiring basic health checks and disclosure to consumers when selling puppies and other pets is harmful to the animals and potentially heartbreaking to the buyers," said Division of Consumer Affairs acting Director Steve Lee.
Dealers must provide buyers with the animal's health history and inform them of their right to return the animal or receive purchase refunds and reimbursement for vet costs if the animal becomes ill within 14 days.
Consumers who believe they have been cheated by a business can file a complaint with the State Division of Consumer Affairs by visiting its website, www.NJConsumerAffairs.com, or by calling 1-800-242-5846 (toll free within New Jersey) or 973-504-6200.