Results of a pseudorabies eradication program on swine breeding farms and case studies on the export of breeding pigs J

en-Chieh Chang

Abstract

In 2011, the Taiwanese Council of Agriculture initiated a pseudorabies (PR) eradication program on pig breeding farms and has started providing PR-free breeding pigs to downstream pig farms and for export. To support the program, the Animal Health Research Institute monitors selected and important swine diseases in breeding pigs. The positive rates of gE antibody ranged from 0.43% to 10.62% in recent years and were significantly decreased from rates as high as 23.7% in 2011. Currently, 15 PR-free swine breeding farms have been approved by the certification committee. Some swine breeding farms took active policy measures and kept following the PR eradication program after the initial participation. One of the recent significant achievements was the successful export of breeding pigs to Vietnam and Hong Kong. Project-oriented quarantine procedures for the export of breeding pigs used the requirements of importing countries as a guide and the needs of the importing countries was a key factor. In addition, other related authorities assisted the pig breeding farms in their export. The main responsibilities of the laboratory were to provide testing services and certification reports. However, tests for a specific set of swine diseases are typically required for each importing country. The set of swine disease tests may also change in terms of timing or the stage of diseases that is highly dependent on quarantine or outbreak conditions on the ground. The AHRI can also provide professional consultation to pig breeding farms and help with negotiations with importing countries regarding quarantine procedures that are advantageous to both sides before export.

The situation of high pathogenicity avian influenza viruses in Taiwan and the investigation of adaptation study

Li-Hsuan Chen

Abstract

Avian influenza (AI) of Taiwan has existed for a long time. The enveloped virus belongs to the family Orthomyxoviridae and composes 8 segments of negative-stranded RNA. The earliest literature of Taiwan can be traced back to the detection of H6N1 subtype in 1972. In addition to the aforementioned H6N1 subtype viruses, there are still viruses of the Mexican H5N2 subtype that have existed since 2003, and the clade 2.3.4.4c H5Nx subtype high pathogenicity avian influenza virus that invaded in 2015 and newly introduced H5N2 subtype high pathogenicity avian influenza virus in 2021. Before 2015, the high pathogenicity avian influenza in Taiwan was mostly derived from the occasional mutation of the low pathogenicity Mexican-like H5N2 subtype virus strain. After 2015, the invasive clade 2.3.4.4c H5Nx subtype high pathogenicity avian influenza virus was the main cause of losses in poultry farms. In recent years, the results of pathogenicity experiments of high pathogenicity avian influenza viruses in chickens have shown that clade 2.3.4.4c H5Nx subtype viruses keep circulating in poultry farms in Taiwan, acquiring better adaptation in chickens.