Essential oils and organic acids, alternatives to antibiotics, effective against E. coli in swine trial
Combining essential oils and organic acids could boost the efficacy of both potential antibiotics alternatives, according to a new study from the University of Manitoba.
Weaned piglets fed a blend of microencapsulated essential oils and organic acids experienced less diarrhea after being exposed to E. coli than pigs that received an untreated diet, according to a report in the Journal of Animal Science. Forty days after their infection with E. coli, the pigs fed essential oils had less diarrhea than another group of piglets fed a diet containing antibiotic growth promoters, according to the study.
“Our results imply that microencapsulated organic acids and essential oils can potentially be implemented in strategies for alternatives to antibiotics in swine production,” Chengbo Yang, an associate professor of livestock nutrition at the University of Manitoba, said in an email.
The University of Manitoba team chose to test a blend of organic acids such as fumaric, citric, malic and sorbic acids alongside essential oils including thymol, vanillin and eugenol on a hunch that the paired oils and acids would have a synergistic effect, Yang said. Essential oils are thought to increase membrane permeability in bacteria, which Yang said could cause the bacteria to become more susceptible to the organic acids.
Specific essential oils, including thymol and eugenol, have been shown to reduce leaky gut in weaned piglets, Yang added.
However, supplementation with the essential oils blend did not significantly reduce the amount of E. coli in the pigs’ gut during the trial. That the blend reduced the piglets’ symptoms anyway could mean the organic acids and essential oils prevented the bacteria from causing disease in some fashion, perhaps thanks to their anti-inflammatory or anti-oxidative properties.
Despite the trial’s promise, Yang said a larger-scale field study was needed to validate the blend’s potential efficacy in commercial settings. The fact that essential oils may exhibit low stability and poor palatability also calls for further evaluation of their practicality, according to Yang.
Yang also cautioned that the blend did not represent a standalone alternative to antibiotics.
“One additive alone cannot replace antibiotics and a combination of different alternatives to antibiotics needs to be considered together with an integrated approach including nutrition, biosecurity and management to maintain herd health,” Yang said.