**4. Conclusions**

According to the Procedural Manual of the Codex Alimentarius Commission (2018), dietary exposure assessments of contaminants in livestock and poultry meat should consider the presence of these contaminants in raw meat as a potential source and account for the effect of food cooking and processing on drug residues. The results of this experiment

indicated that the changes in drug residues in livestock and poultry meat depended on the cooking time, the methods and the type of food matrices. Under both boiling and deep-frying cooking methods, extended heating time effectively reduced the concentration of the four drug residues, thereby reducing the risk of dietary exposure to consumers. However, microwaving led to increased drug residue concentrations. Although boiling and deep-frying cooking are both effective ways to reduce residues of amphenicols and metabolites in meat, there is no guarantee that these residues will always decrease to a safe level in terms of consumer health, especially when drug residue concentrations in raw livestock and poultry meat are higher than the MRLs. In summary, from the safety and toxicological point of view, it is unsafe to rely on cooking to remove residues of amphenicols and metabolites from food. The solution to the food safety problem of veterinary drug residues must start at the source—from the production, operation and use of veterinary drugs—to strengthen supervision in order to establish a regulated veterinary drug market order.

**Author Contributions:** Conceptualization, M.W., X.W. and W.W.; methodology, M.W. and X.W.; software, M.W. and X.W.; validation, W.W., X.C. and H.Q.; formal analysis, X.C.; investigation, H.Q.; resources, W.W. and X.C.; data curation, X.W.; writing—original draft preparation, M.W.; writing review and editing, M.W., W.W. and H.Q.; supervision, W.W. and X.C.; funding acquisition, W.W. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research was funded by the National Key Research and Development Projects (Intergovernmental International Cooperation in Science and Technology Innovation Program), grant number 2019YFE0103800.

**Institutional Review Board Statement:** Not applicable.

**Informed Consent Statement:** Not applicable.

**Data Availability Statement:** Data are contained within the article.

**Acknowledgments:** The authors would like to thank Wangang Zhang for his guidance and revision of this article and the Supervision, Inspection and Testing Center for Quality of Meat-Products, Ministry of Agriculture and Rural Affairs (Nanjing, China) for providing instrumentation support.

**Conflicts of Interest:** The authors declare no conflict of interest.
