WICHITA, Kan. -

Petco is the first national chain to announce it'll stop carrying pet treats from China by the end of the year.  That move follows more than 1,000 deaths of American dogs and more than 5,600 illnesses believed to be related to jerky treats made in China. Petsmart announced Wednesday it will also stop selling the treats made in China.

In the meantime, the FDA continues to search for what specifically in the treats may be killing the pets.  Researchers have found traces antibiotic and antiviral medication in several brands of the Chinese products.  But they have not found the specific link to what has led apparently killed animals which ate the snacks.

Wichita dog owner Henry Rooney just found out about this.  He says he always buys bargain treats for his dog, Moose, but never noticed where they were made.  Now, he's concerned.

"Our dog is part of our family," Rooney says.  "It's heartbreaking to think about me losing my dog over  a snack."

The FDA is not listing what specific brands to avoid, just ones that say they're made in China.  Although, that's no guarantee either, because factories in other countries may use ingredients from China, and there's no way of knowing that.

Petco says the treats should completely be out of stores by the end of this year.

Fact Finder 12 investigated why it would take months for the products to be removed. Petco says that years ago, 90% of the industry's chicken jerky came from China. Today, about 50% come from this country.

Petco says it takes time to find and transition to new suppliers.

The company says many customers use the products every day without issue, and it wants to continue to supply pet treats to those customers during the transition.

The FDA hasn't been able to directly prove that the treats made in China are making pets sick, but has received 48,000 complaints.

Click here to read to Petco's announcement on the dog treats.

Click here to read more about the illness that's killing pets.