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A complaint against a long-time Fort Worth veterinarian alleges some animals that the owners believed were euthanized were kept alive. The accusers told investigators the vet wanted the animals for their blood.

Fort Worth police and medical board investigators raided the Camp Bowie Animal Clinic on Tuesday, acting on a complaint filed by Marian Harris against Dr. Lou Tierce.

"The betrayal is so incredibly intense,” said Harris, a former client of the clinic.

The Harris family took their 170-pound dog, a Leonberger named Sid, to Tierce in May of last year. In October, the family was told Sid had a congenital birth defect.

According to the complaint filed with the Texas State Board of Veterinary Medical Examiners, "Mr. Harris asked whether there was anything that could be done to cure this condition, and Dr. Tierce restated that nothing could be done," and Sid would have to be put down.

"So I brought him in and had our tearful goodbyes, and we went over very specifically our plans for burial of Sid, and that was the end of it,” she said.

Former clinic employee Mary Brewer said she was working there when Sid was allegedly supposed to be euthanized. But six mother later, she says she saw Sid alive and gave the Harris family the disturbing news.

"I remember coming in and them extracting blood from Sid, and basically shaving him, extracting his blood for the other animal upstairs,” said Brewer.

According to the complaint, "The clinic was using Sid (and other dogs) for blood transfusions and other experimental treatments.”

Harris actually managed to steal her dog back, and then confronted Tierce, who reportedly declined to comment on the allegations.

According to the complaint, another veterinarian examined Sid and determined that among other things, "he had mange and shows definite signs of having been used for blood transfusions.”

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