Ha Thi Thanh Tran(1,¥), Anh Duc Truong(1,¥), Duc Viet Ly(1), Tuan Van Hoang(1), Nhu Thi Chu(1), Huyen Thi Nguyen(1), Anh Thi Kieu Dang(1), Maartje De Vos(2), Kobe Lannoo(2), Geert Bruggeman(2) and Hoang Vu Dang(1*)
1- Department of Biochemistry and Immunology, National Institute of Veterinary Research (NIVR), 86 Truong Chinh, Dong Da, Hanoi 100000, Vietnam
2- Royal Agrifirm Group, Landgoedlaan 20, 7325 AW Apeldoorn, The Netherlands
¥Authors contributed equally to this work
Background: African swine fever (ASF) is an important disease affecting swine and has a significant economic loss in both the developed and developing world.
Aim: In this study, we evaluated the potential effects of MCFAs in individual and synergistic forms to prevent and/or reduce ASFV infection using in vitro feed model.
Methods: The cytotoxicity of MCFAs on PAM cells was evaluated by using the MTT assay. The potential effects of MCFAs, including C8 (caprylic acid), C8-C6-C10 (caprylic acid-caproic acid-capric acid; 1:1:1 ratio) and C8-C10-C12 (caprylic acid-capric acid-lauric acid; 1:1:1 ratio) against a field ASFV strain isolated in the capital Hanoi of Vietnam, were further examined by real-time PCR and HAD assays in in vitro feed model.
Results: Our results indicated that all tested products do not induce cytotoxicity at the dose of 100 µg/ml and are suitable for further in vitro examination. These products have shown a strong antiviral effect against ASFV infectivity at doses of 0.375% and 0.5%. Interestingly, the synergistic MCFAs have shown clearly their potential activities against ASFV in which at a lower dose of 0.25%, pre-treatment with product 2 and 3 induced significant increases at the level of Cq value when compared to positive control and/or product 1 (P<0.05). However, the viral titre was not changed after 24h post-inoculation when compared to positive control. Our findings suggested that all tested products, both individual and synergistic forms of MCFAs, have possessed a strong anti-ASFV effect, and this effect is dose-dependence in in vitro feed model. Additionally, synergistic effects of MCFAs are more effective against ASFV when compared to individual forms.
Conclusion: Together, the findings in this study indicate that MCFAs, both individual and synergistic forms, inhibit against a field ASFV strain in the feed model, which may support minimizing the risk of ASF transmission in the pig population. Further studies focusing on in vivo anti-ASFV effects of MCFAs are important to bring new insight into the mode of ASFV-reduced action by these compounds in swine feed.
Keywords: African swine fever virus, virus isolation, MCFA, pig, Vietnam.
Cite this paper:
Tran, H.T.T., Truong, A.D., Ly, D.V., Hoang, T.V., Chu, N.T., Nguyen, H.T., Dang, A.T.K., De Vos, M., Lannoo, K., Bruggeman, G. and
Dang, H.V. 2021. The potential anti- African swine fever virus effects
of medium chain fatty acids on in vitro
feed model: An evaluation study using epidemic ASFV strain circulating in
Vietnam. Open Vet. J. 11(3), 346-355.