LOS ANGELES (AP) -- All that's left of Doodles are his ashes, a clay impression of his paw and a whole lot of questions owner Patricia Cassidy has about his mysterious death.
Doodles is believed to be one of 580 dogs in the U.S. that have died in the past six years from eating pet jerky from China. Baffled by the cause and seeing another surge in illnesses, the Food and Drug Administration reached out to owners and veterinarians Tuesday to help it find the poison behind the sickening of at least 3,600 dogs and 10 cats since 2007.
Within hours of eating the suspect jerky, pets lost their appetite, became lethargic, vomited and had diarrhea and other symptoms. The strips made of chicken, duck, sweet potatoes or dried fruit were sold under a variety of brand names.
There was a decrease in 2007 after some products were voluntarily removed from the market, but the FDA said it didn't want to conduct a recall without a definitive cause. Those products included Milo's Kitchen Chicken Jerky Treats and Chicken Grillers, made by Del Monte, and Waggin' Train and Canyon Creek Ranch dog treats, made by Nestle Purina.
But in the years since, the FDA has gotten complaints from pet owners and veterinarians who have seen repeated cases of kidney failure, gastrointestinal bleeding, and a rare kidney disorder, the FDA said.
The FDA's Center for Veterinary Medicine has run more than 1,200 tests, visited pet treat manufacturing plants in China and worked with researchers, state labs and foreign governments but hasn't determined the exact cause of the illness.
Testing is complicated because the poison may have come from the manufacturing plant, shipping, transportation or anywhere along the way. Scientists have to know what they're looking for to test for it.
In Chattanooga, Tennessee, Doodles died Sept. 9 at the age of 6. In just three months, he turned from a vibrant 16-pound (7.2-kilogram) shih tzu into a frail, 6-pound (2.7 kilograms) animal who couldn't eat or drink and had so little left in him he could only vomit yellow bile.
"He was such a loving little guy and so cute. Every day my daughter will say, 'Mom, I don't know when the holes in our hearts will be repaired.'"
Cassidy promised Doodles she would wage war as long as it took to get the products off store shelves or, at the very least, labeled so people know it might be deadly.
The jerky mystery is the worst case of tainted pet food from China since 2007 when there was a nationwide recall of food made by Menu Foods and 1,950 cats and 2,200 dogs died. Kidney failure caused all of those pet deaths and the poison was found to be tainted melamine from plastic packaging in the wheat gluten. About 150 brands of dog and cat food were recalled and included some of the biggest names in pet food.
A federal grand jury indicted two Chinese nationals and the businesses they operate, as well as the U.S, company ChemNutra Inc. and its CEO for their roles in importing the poisonous products. A class-action lawsuit awarded more than $12.4 million in compensation to pet owners whose pets died from the poisoned food.
Veterinarians can only tell pet owners they don't know what's causing their animals to get sick and that's hard to do, said Dr. Karl Jandrey, an emergency and critical care vet at the Veterinary Medical Teaching Hospital at the University of California, Davis. They have treated several dogs for what they believe was poisoning from the treats, but no patient has died, he said.
Dexter, a 3-year-old, 19-pound (8.6-kilogram) miniature schnauzer also survived, but it cost owner Rich Phillips of North Richland Hills, Texas, about $1,200, he said.
In April, Dexter started throwing up and couldn't stop. He spent the night at an emergency clinic and the next day at the vet's. Test after test was inconclusive. The dog was given an IV and anti-nausea medicine and sent home. That's when Phillips saw the package of chicken jerky treats and knew that was the cause. "We were lucky we caught him quick," Phillips said. Dexter had only had about two of the treats and has been fine ever since that night.
No one knows how many treats a pet has to eat before it starts getting sick, said Dr Amy Bowman, regional medical director for Banfield Pet Hospital in Virginia.
"Some say it's a single serving, some say the whole bag," she said. Her advice is to avoid jerky treats if the label says it comes from China. There are all kinds of healthy treat substitutes, including apples, uncooked green beans and carrots, she added.
A lot of pet owners transfer food and treats into other containers at home to keep pets and pests out, but some experts suggested keeping labels with lot numbers and manufacturers.
Imported pet food is inspected when it arrives in the United States but only randomly and to check for things like mold, said Dr. Tina Wismer, medical director of the Animal Poison Control Center of the American Society for the Prevention of Cruelty to Animals.
Dr. Barry Kellogg, senior adviser to the Humane Society Veterinary Medical Association, called for increased testing and stricter guidelines on labeling of imports. If only part of a product is from China and it is put together in the United States, labels don't have to say made in China, he said.
Writer Mary Clare Jalonick reported on this story from Washington.