BOSTON -- Most pet owners in Massachusetts get excellent care for their animals from their veterinarians. But not all. Team 5 Investigates' Sean Kelly reported Tuesday that dozens of veterinarians continue to practice even though they have a long history of complaints.

"Clover," a 14- year-old calico cat, is like a family member to Wendy Moore of Arlington, Mass. That's why Moore immediately noticed something wrong the day after her cat got a routine enema at the vet. "She literally didn't respond to anything. It was like she was dead. She was having kidney failure and she had a massive infection," said Moore.

The infection eventually spread to two of Clover's legs.

"Did you think Clover was dying?" asked Kelly. "Yeah, because she didn't respond at all" said Moore.

Moore filed a complaint against Dr. Mohammed Taqiuddin, a veterinarian with offices in Arlington and Cambridge, for Clover's problems and for ignoring her concerns.

"He said oh, don't worry about it...everything's fine," said Moore.

Moore was shocked when the state Board of Registration in Veterinary Medicine dismissed her complaint. She said she was also surprised to learn she wasn't the first to complain.

"One of the things I found out is that Dr. Taqiuddin had been investigated 13 times," said Moore.

Team 5 Investigates learned Taqiuddin has been reported to the Board a total of 15 times since he was licensed in 1981. Complaints against him show alleged incompetence and unsanitary conditions in his clinic.

The Board of Registration in Veterinary Medicine dismissed all but one of those complaints and put him on probation back in 1995. Board members also fined him $200 for improperly storing and using outdated medication this past year. Some of those drugs were 14 years old.

"That's very worrying. I would be concerned with a veterinarian who had that many complaints," said Susan Weinstein, executive director of the Massachusetts Veterinary Medical Association.

"What's typical in terms of the amounts of complaints?" asked Kelly.

"A veterinarian can expect one or fewer complaints at the board of registration during their professional career," answered Weinstein.

Team 5 Investigates found there are dozens of vets with many more complaints than just one.

A review of state records found 65 veterinarians with at least five complaints. One veterinarian has been reported to the board 17 times.

"What would make me uneasy is knowing that somebody has discipline against them, not a complaint," said George Weber, director of the Division of Professional Licensure. Weber oversees the state Board of Registration in Veterinary Medicine.

"Why should these people be allowed to practice?" asked Kelly.

Weber said "73% of the individuals who have five or more complaints have had disciplinary action taken against them by the board. That shows the board is diligently protecting consumers and animals."

But what about veterinarians like Dr. Taqiuddin who has been reported to the board time after time for the same problems?

"We have inspected Dr. Taqiuddin twice in the last four years and once we found violations, another time we didn't, so we are actively monitoring him," said Weber.

However the Board's inspections are not a surprise and critics like Jonathan Rankin, an animal law attorney, said neither is the Board's inaction.

"Why aren't vets being held accountable?" asked Kelly.

"I think their window of what they're accepting as acceptable care might be a little wider than what the acceptable level of care standard is," answered Rankin.

Team 5 Investigates tried to talk to Dr. Taqiuddin on the phone and at his clinic, but he refused.

"There's ongoing investigations and Dr. Taqiuddin and I don't want to jeopardize anything," said his attorney, Ben Weisbuch.

"How does Dr. Taqiuddin explain why he has 15 complaints against him?" asked Kelly.

"I think it's easy to make a complaint in this state. Dr. Taqiuddin uses the procedures that qualified doctors use in this state. He's been doing it for 27 years and he's never had his license suspended," answered Weisbuch.

Critics of the Board tell Team 5 that's exactly why they're so concerned.

"There is no place to go. I mean if the board of licensing determines that the case ends, there is no other place to go," said Moore.

What can you do to make sure your veterinarian is a good one?

Don't rely solely on the Board's website. The state doesn't list the number or nature of complaints filed against a veterinarian. And when they do take action against someone, the details of why that vet was disciplined are not included. The state said there are no plans to change that.