**4. Materials and Methods**

#### *4.1. Ethics Statement*

This research was reviewed and approved by the Ethics Committee of the South China Agricultural University. The fecal specimens were collected with the permission of the owners of the pets. Each sample was collected and placed into a 50-mL plastic centrifuge tube containing 2.5% potassium dichromate and was transferred to the laboratory for storage at 4 ◦C. The DNA extraction was completed within one week. The DNA was stored at −20 ◦C for less than three years before being used in the PCR analysis in the present study.
