This is the latest scandal involving chickens in China.

In December, China Central Television revealed that Liuhe Group — a former chicken supplier of Yum Brands, which owns KFC — had been providing chickens with excessive traces of antibiotics and hormones.

The chickens were fed the drugs to reduce the death rate and shorten their growth period.

Yum in China later admitted excessive antibiotic traces were found in several batches of chicken samples from Liuhe between 2010 and 2011, but it did not disclose the fact as it was not obligated to reveal test results conducted by itself, according to Chinese law.

Yum also said it had terminated cooperation with Liuhe in 2012.

The State Food and Drug Administration said on Tuesday it encourages people to disclose food safety problems.

Whistleblowers can be rewarded with as much as 300,000 yuan ($48,000) for reporting cases, according to an announcement.

Shi Baoyin in Zhengzhou contributed to this story.

Contact the writer at wangxiaodong@chinadaily.com.cn