Plant-derived extracts and essential oils hold promise as an alternative to antibiotics during the weaning process, but producers may need to feed the plant extracts directly to piglets to see any effect, according to a study on plant extract supplements from France's National Research Institute Agriculture, Food and Environment (INRAE).
In the study, researchers from INRAE and animal nutrition firm Idena provided nursing sows and piglets with various supplements composed of powdered plant extracts, essential oils and organic acids. While the piglets that received the supplements directly experienced improved growth outcomes during the post-weaning period, piglets born from the supplemented sows did no better than those that did were not fed the supplements.
Essential oils and other plant extracts have gained attention as potential feed additives thanks to their antimicrobial, antioxidative, immune-promoting and anti-inflammatory properties, said Lucile Hervé, an INRAE researcher and the lead author on the paper. The plant extracts selected for the study — which included oils and powdered extracts from eucalyptus, oregano, fenugreek, Siberian ginseng and other plants — were all selected for benefits demonstrated in previous research studies, Hervé said.
The research team expected the plant-based supplements to improve the health of piglets during the precarious post-weaning period by boosting the immune system and improving their ability to face weaning. But they also believed providing supplements to the sows would change the colostrum and milk composition, providing piglets with additional support.
Hervé said changes to the duration, timing or dose of the maternal supplements may be needed to achieve the desired effect — adjustments that also apply to the use of plant extracts during weaning and across a pig's lifespan.
“The use of plant extracts especially in the context of weaning is a promising way improve piglet health and robustness, and reduce the use of antibiotics,” Hervé said, “but research remains to be done to recognize the most effective dosage, moment and duration of supplementation and combinations of plant extracts and to fully understand their mechanisms of action.”
Numerous plant-based supplements are already available to pig producers, and Hervé said she thought they should be considered as a preventative strategy to help piglets face the challenge of weaning. However, the supplements should be used in addition to, and not as a replacement for, strategies such as improved biosecurity, vaccination, and the use of prebiotics and probiotics.