*4.7. Statistical Analysis*

All statistical analyses were performed using the GraphPad Prism software, version 6.0, for Windows. Data were analyzed using one-way analysis of variance, followed by Tukey's multiple-comparison test. Groups showing significant differences (*p* < 0.05) at the same time point are indicated by different letters.

**Supplementary Materials:** The following are available online at http://www.mdpi.com/2076-0817/8/4/251/s1. Amino acid differences between commercial LOM vaccine strains and Jeju LOM strains (2004–2007), Table S1: (https://zenodo.org/deposit/3484007) and (2014–2018), Table S2: (https://zenodo.org/deposit/3484007). Positively selected sites and omega values for the Jeju LOM strains, Table S3: (https://zenodo.org/deposit/3484007).

**Author Contributions:** I.-S.C., B.-H.H., B.-K.P. and D-.J.A. conceived the study; S.C., J.-H.K. and D.-J.A. designed the experiments; S.C., J.-H.K., K.-S.K., S.S., W.-C.K., H.-J.K., G.-N.P. and R.-M.C. performed the experiments; J.-H.K., W.-C.K. and H.-J.K. acquired samples; S.C., R.-M.C. and D.-J.A. drafted the manuscript. All authors read and approved the final version.

**Funding:** This project was supported by grants (Project Code no. B-1543083-2017-18-02 and B-1543083-2019-21-02) from the Animal and Plant Quarantine Agency and Ministry of Agriculture Food and Rural affairs, Republic of Korea.

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

**Ethical approval and consent to participate:** All clinical samples were submitted to the College of Veterinary Medicine of Jeju National University on Jeju Island, and the Animal Hygiene Laboratory on Jeju Island. All animal experiments were approved by the Animal and Plant Quarantine Agency in Ministry of Agriculture Food and Rural affairs. All pig farm owners consented to participate.
