Dataset Information

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.

ABSTRACT:

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 medium-chain fatty acids (MCFAs) in individual and synergistic forms to prevent and/or reduce ASF virus (ASFV) infection using in vitro feed model.

Methods

The cytotoxicity of MCFAs on porcine alveolar macrophages cells was evaluated by using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide 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 haemadsorption 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 two and three 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 24 hours 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.

SUBMITTER: Tran HTT

PROVIDER: S-EPMC8541713 | biostudies-literature | 2021 Jul-Sep

REPOSITORIES: biostudies-literature

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The potential anti-African swine fever virus effects of medium chain fatty acids on <i>in vitro</i> feed model: An evaluation study using epidemic ASFV strain circulating in Vietnam.

Tran Ha Thi Thanh HTT Truong Anh Duc AD Ly Duc Viet DV Hoang Tuan Van TV Chu Nhu Thi NT Nguyen Huyen Thi HT Dang Anh Thi Kieu ATK De Vos Maartje M Lannoo Kobe K Bruggeman Geert G Dang Hoang Vu HV

Open veterinary journal 20210715 3

<h4>Background</h4>African swine fever (ASF) is an important disease affecting swine and has a significant economic loss in both the developed and developing world.<h4>Aim</h4>In this study, we evaluated the potential effects of medium-chain fatty acids (MCFAs) in individual and synergistic forms to prevent and/or reduce ASF virus (ASFV) infection using <i>in vitro</i> feed model.<h4>Methods</h4>The cytotoxicity of MCFAs on porcine alveolar macrophages cells was evaluated by using the 3-(4,5-dim ...[more]

PMID: 34722195

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