Amantadine may exist in test samples of raw chicken belonging to Yum Brands, which owns the fast food chain KFC, according to the Shanghai Food and Drug Administration.

On Tuesday, the administration carried out tests on samples of raw chicken products from a logistics center belonging to Yum Brands in Shanghai after China Central Television reported that some chicken farms in Shandong province feed the birds with excessive amounts of antibiotics to reduce their mortality rate and make them grow faster.

The CCTV report said that the chickens - which had inferior health conditions and reached full growth within about 40 days - were sold to the suppliers of KFC.

The administration released the preliminary test result on Friday and said amantadine may exist in the samples.

Amantadine is used both as an antiviral and an antiparkinsonian drug, according to experts.

So far, there is no standard for the test for amantadine in China, and the preliminary test result requires further confirmation, the administration said.

Officials said they are organizing experts to carry out food safety risk assessment.