**Xiujuan Chen ID , Linhai Wu \* and Xuyan Xie**

Institute for Food Safety Risk Management, School of Business, Jiangnan University, Wuxi 214122, China; xjchen@jiangnan.edu.cn (X.C.); xiexuyan1@yahoo.com (X.X.)

**\*** Correspondence: wlh6799@jiangnan.edu.cn; Tel.: +86-135-0617-9899

Received: 29 March 2018; Accepted: 29 May 2018; Published: 31 May 2018

**Abstract:** Improper use of veterinary antibiotics (VAs) has led to antibiotic resistance and food safety issues that are harmful for sustainable development and public health. In this study, farmers' knowledge influencing their usage of veterinary antibiotics was analyzed based on a survey of 654 pig farmers in Funing County, China. A behavior probability model was constructed, and a Matlab simulation was used to evaluate the dynamic changes in farmers' behavioral choice regarding VAs use. The survey results showed that the 654 pig farmers' knowledge of VAs were relatively poor, along with a high occurrence of improper behavior. Specifically, 68.35% of the 654 surveyed pig farmers admitted their violation of VAs use regulations, while 55.50% among them overused and 24.31% among them misused VAs. The simulation results showed that the probability of improper VA use decreased with the increase in farmers' knowledge about VA use specification, and when farmers' knowledge about the hazards of VA residues increased. However, when farmers had a high level of knowledge about relevant laws and their penalties, there was still a high probability of improper VA use.

**Keywords:** farmer; veterinary antibiotics use; knowledge; behavior probability model; China
