Do Natural feed additives improve gut health and performance in pigs?
A long-term study conducted by researchers at the Arkansas Agricultural Experiment Station, part of the University of Arkansas System Division of Agriculture, has highlighted the potential of plant-based essential oils as alternatives to antibiotic growth promoters in swine production.
Researchers studied the effects of oregano and rosemary extracts on pig health and growth, comparing them with traditional antibiotic use.
“This study allowed us to look at the lifetime impact from phytochemical exposures,” said Tsungcheng “TC” Tsai, Ph.D., a program associate in the department of animal science for the experiment station, the research arm of the University of Arkansas System Division of Agriculture.
“If you just look into the nursery phase — the first 43 days after weaning — and you don’t see any difference, the study is ended, and you don’t really know the true value of those phytochemicals,” said Tsungcheng.
The study condusted by Tsungcheng focused on weaned piglets, a stage that is often stressful due to dietary and environmental changes. During this phase, pigs are vulnerable to gut health issues that can impact their growth and overall performance.
To understand long-term effects, researchers divided 192 piglets into different groups, including those receiving antibiotics, those given essential oils, and a control group.
While pigs fed with antibiotics showed faster early growth, this advantage did not last. Once antibiotics and high levels of zinc were removed from their diet, their growth slowed down.
In contrast, pigs that received essential oils continuously showed better results over time. By the end of the study, these pigs achieved higher body weight and better feed efficiency.
The research also examined the gut microbiome, which plays an important role in digestion and health. Pigs given antibiotics showed reduced microbial diversity and a higher presence of harmful bacteria. However, those fed with essential oils had a healthier and more balanced gut microbiome. Beneficial bacteria increased, supporting better digestion and nutrient use.
Another concern with antibiotics and zinc is their environmental impact and contribution to antimicrobial resistance. Excess zinc in pig waste can harm soil and plants, while overuse of antibiotics can reduce their effectiveness over time.
“It’s an encouraging step toward more sustainable and responsible pork production,” said Professor and Department Head Michael Looper. “Consumers want food that’s raised responsibly, and this study gives swine farmers more natural tools to do just that. It’s exciting to see options that support animal health while helping produce pork that people can feel good about.”
The findings suggest that essential oils may not provide immediate results like antibiotics, but they support long-term health and growth. Researchers also observed that pigs fed with these natural compounds appeared less aggressive.
Overall, plant-based essential oils offer a promising and sustainable solution for improving swine health while reducing reliance on antibiotics in modern farming.
Photo: Oregano
Photo Credit: Pexels - Nikolett Emmert