Abstract: Objective: To compare the swabbing and rinsing methods used for sampling chilled chicken by evaluating their effects on microbial DNA extraction and subsequent high-throughput sequencing. Methods: Four chilled chickens were divided into equal halves and sampled by superficial swabbing and rinsing methods for each half, respectively. Microbial genomic DNA was extracted from the collected samples and the V3-V4 region of the bacterial 16S rRNA gene was amplified by PCR. The PCR products were then subjected to high-throughput sequencing on an Illumina HiSeq sequencing platform. The obtained sequences were processed and analyzed using QIIME and other softwares. Results: There was no difference in bacterial genomic DNA extraction or bacterial community richness, diversity and structures between the samples collected by the two methods (P > 0.05). High-throughput sequencing showed that the bacterial community in chilled chicken samples consisted mainly of 7 phyla and 10 genera. Proteobacteria was the dominant phylum, accounting for more than 70% of the bacterial community; Shewanella, Pseudomonas, Acinetobacter, Psychrobacter, and Brochothrix were the dominant genera, each representing 10%?20% of the bacterial community. Conclusions: The two sampling methods exhibit no obvious difference in bacterial DNA extraction from chilled chicken or high-throughput sequencing. However, compared with swabbing, rinsing has the advantages of easy operation and non-secondary contamination, so it is more practical in microbiological analysis of chilled chicken. The experiment also provides useful data for the study of bacteria on chilled chicken.

Key words: chilled chicken, bacterial community, swabbing method, rinsing method, high-throughput sequencing