Interpretive Summary: Assessing the effects of medium-chain fatty acids and fat sources on PEDV infectivity
By: Anne Wallace
Mitigation of porcine epidemic diarrhea virus (PEDV) infections in the swine industry is a challenge. Contaminated feed can infect pigs because PEDV spreads by fecal-oral transmission. Although heat processing destroys PEDV in feed, it is ineffective if contamination occurs after processing. Therefore, additional ways to reduce the risk of PEDV are needed.
The authors of this April 2020 Translational Animal Science paper looked at medium chain fatty acids (MCFA) – a “mitigation additive” – in pig feed. Their goal was to see if MCFAs reduced the risk of pigs contracting PEDV. They compared MCFA to other additives and determined which, if any, were effective mitigators.
Pigs were fed a corn/soybean meal-based diets with PEDV and one of 17 different additive formulations. The 18th diet was a negative control with no PEDV and no mitigation additives. Various concentrations of caproic, caprylic, capric, and lauric acids, blends of MCFAs, and canola oil, white grease, coconut oil, palm kernel oil, soy oil, and a C12 commercial product were tested. A diet with formaldehyde-based mitigation additive was also included. Formaldehyde-based mitigation additives are effective against PEDV, however, due to consumer safety concerns are an unfavorable choice.
Less viral particles were found in feed containing MCFA (blended or individual) and formaldehyde, but not other additives. Additionally, PEDV infectivity was inhibited in pigs fed caproic acid, caprylic acid, capric acid, and a blend of caproic, caprylic and capric acids. Formaldehyde also inhibited PEDV infectivity.
Overall, the results of this study suggest that MCFAs are likely effective in reducing PEDV viral particles in contaminated feed and the subsequent risk of infection in pigs fed contaminated feed. More studies are needed to better understand the mechanism behind the effectiveness of MCFA as a mitigation tool and how it can be optimized to reduce the risk of PEDV infection in pigs.