Yanliang HE^1,2, Zhenguang LI^1,2*, Weiwei SU^1,2, Dongmei YUE², Caichao Zhan², Xijun Yan², Guangqiang Zhu¹ and Hua WU²

¹College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China
²Sinovet (Jiangsu) Biopharm. Co., Ltd., Taizhou, Jiangsu, China

*Corresponding Author: Zhenguang LI, 1College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangs and Sinovet (Jiangsu) Biopharm. Co., Ltd., Taizhou, Jiangsu, China.

Received: June 19, 2023 Published: November 03, 2023

Abstract

In the study the protective efficacy of a live attenuated and an inactivated porcine reproductive and respiratory syndrome vaccine was comparatively evaluated. A total of 55 healthy piglets, which were negative to PRRSV antigen and antibody, were randomly divided into 4 groups. In group 1, 20 piglets were immunized with PRRS live vaccine TJM-F92 strain (Live vaccine TJM-F92). In group 2, 20 piglets were inoculated with commercial PRRS inactivated vaccine (Inactivated vaccine). Piglets of group 3 (n = 10) were inoculated with PBS (Negative control). 5 piglets remained as a not-immunized and not-challenged in control group 4 (Mock group). At 49 days post immunization (dpi), 10 piglets from groups 1 and 2 were selected and challenged with HP-PRRSV TJ strain and PRRSV NADC30-like strain respectively. The results showed the level of antibodies arose from live vaccine was significantly higher and faster than that from inactivated vaccine after immunization. In live vaccine immunized group, neither high fever nor signs of clinical disease were observed. While piglets in inactivated vaccine group exhibited serious clinical symptoms, pathological lesions, and viremia load after HP-PRRSV TJ strain challenge. There were no severe clinical signs, gross pathology lesions and viremia load in live vaccine group, however, severe clinical syndromes, pathology change of lungs and high viremia load were recorded in piglets of inactivated vaccine immunized group after NADC30-like strain challenge. Those results suggested that PRRS live vaccine (TJM-F92 strain) could confer effective protection against the challenge of HP-PRRSV TJ strain and virulent NADC30-like strain. The PRRS inactivated vaccine could not effectively induced immune system and provide strong immune cross-protection. Therefore, it is essential to choose suitable, widely application and effective PRRS vaccine for PRRS control according to the situation of pig farms.

Keywords: PRRSV; Live Vaccine; Inactivated Vaccine; Protective Efficacy

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Citation

Citation: Zhenguang. “Comparison Between Protective Efficacies of Live Attenuated and Inactivated Vaccines for the Prevention of Porcine Reproductive and Respiratory Syndrome".Acta Scientific Veterinary Sciences 5.11 (2023): 03-13.

Copyright

Copyright: © 2023 Zhenguang. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.