When piglets are weaned off their mother’s milk, their bodies go through a stressful change that makes them more likely to get sick. Researchers wanted to know if giving mother pigs a special live yeast supplement during pregnancy and nursing could help their babies stay healthier. They found that piglets born to yeast-supplemented mothers had less inflammation and stronger immune responses when exposed to harmful bacteria. This suggests that what mothers eat during pregnancy and nursing might help protect their babies during this vulnerable time.

The Quick Take

  • What they studied: Whether giving mother pigs a live yeast supplement during pregnancy and nursing would help their babies handle stress better and fight off infections after weaning
  • Who participated: 40 pregnant pigs were divided into two groups: one received regular feed, the other received feed with added live yeast. After birth, 16 piglets from each group were selected and tested
  • Key finding: Piglets whose mothers ate yeast had lower levels of inflammatory chemicals in their intestines when exposed to harmful bacteria, and their bodies showed signs of better immune protection
  • What it means for you: This research suggests that maternal nutrition during pregnancy and nursing may help babies develop stronger immune systems. While this study was in pigs, the findings could eventually inform how we think about nutrition for pregnant people and nursing mothers

The Research Details

Researchers started with 40 pregnant pigs. Half received normal feed, and half received feed containing live yeast (a type of beneficial microorganism) from day 77 of pregnancy through nursing. After the piglets were weaned, researchers selected 16 healthy piglets from each mother group and divided them into four smaller groups. Two groups received a harmless salt injection, while two groups received an injection of lipopolysaccharide (LPS), which is a substance that mimics a bacterial infection and triggers an immune response. This allowed researchers to see how the piglets’ bodies reacted to a simulated infection.

The researchers measured the piglets’ body temperature every hour for 4 hours after injection. Then they collected tissue samples from the intestines, liver, and lymph nodes to examine immune markers and inflammatory chemicals. They used laboratory techniques to measure specific proteins and genes that indicate how strong the immune response was.

This study design is important because it tests whether something the mother eats can actually change how the baby’s immune system works. By using a controlled bacterial challenge, researchers could measure real immune responses rather than just guessing. This approach helps prove cause-and-effect rather than just showing a connection.

This is a controlled experimental study, which is a strong research design. The researchers randomly assigned mothers to treatment groups, which reduces bias. However, the study was conducted in pigs, not humans, so results may not directly apply to people. The sample size was moderate (40 mothers, 64 piglets tested), which is reasonable for this type of animal research. The study measured multiple immune markers, which strengthens the findings.

What the Results Show

Piglets whose mothers received yeast supplementation showed several signs of better immune protection when exposed to the bacterial challenge. Most notably, these piglets had significantly lower levels of TNF-alpha (a chemical that causes inflammation) in their intestinal tissue compared to piglets from non-supplemented mothers. Additionally, piglets from yeast-supplemented mothers had lower levels of certain immune activation markers in their liver tissue, suggesting their bodies weren’t overreacting to the bacterial challenge.

The researchers also found that piglets from yeast-supplemented mothers had higher levels of protective proteins in their intestinal lining, specifically a protein called E-cadherin that helps maintain the barrier between the intestines and the bloodstream. This is important because a strong intestinal barrier prevents harmful bacteria from entering the body.

Interestingly, piglets from yeast-supplemented mothers showed a slightly lower body temperature increase in response to the bacterial challenge, though this difference was borderline statistically significant. This suggests their bodies were mounting a more controlled immune response rather than an excessive inflammatory reaction.

The study found that piglets from yeast-supplemented mothers had higher levels of certain immune-related genes in their intestinal tissue, including genes for IL-6, IL-10, TNF-alpha, and IL-1 beta. While some of these are inflammatory chemicals, the pattern suggests a more balanced and controlled immune response. In the lymph nodes (which are part of the immune system), piglets from yeast-supplemented mothers had lower activation of NF-kappa B and myeloid differentiation factor 88, which are key switches that turn on inflammatory responses. This indicates that the immune system was better regulated.

Previous research has shown that live yeast can act as both a probiotic (beneficial bacteria) and prebiotic (food for beneficial bacteria), helping to improve gut health and immune function. This study extends that knowledge by showing that maternal consumption of live yeast may transfer immune benefits to offspring. The findings align with growing evidence that what mothers eat during pregnancy and nursing influences their babies’ long-term health and immune development. However, most previous studies focused on direct supplementation of the babies, not maternal supplementation, making this research a novel contribution.

This study was conducted in pigs, not humans, so we cannot directly apply these findings to people without further research. The study used an artificial bacterial challenge (injection of LPS) rather than a natural infection, which may not perfectly mimic how real infections work. The sample size, while appropriate for animal research, was relatively small. The study only measured immune markers at one time point (4 hours after injection), so we don’t know if benefits lasted longer. Additionally, the study didn’t track the piglets’ long-term health or growth, so we don’t know if these immune changes translated to better overall health outcomes.

The Bottom Line

Based on this research, there is moderate evidence that maternal live yeast supplementation may help offspring develop better immune resilience during stressful transitions. However, these findings are from animal studies and should not be directly applied to human nutrition without additional human research. For pig farmers, this suggests live yeast supplementation of pregnant and nursing sows may be worth considering as a low-risk strategy to improve piglet health. For people, this research is interesting but preliminary—more human studies are needed before making dietary recommendations.

This research is most relevant to livestock producers and veterinarians working with pigs. It may also interest researchers studying maternal nutrition and immune development in humans. Pregnant people and nursing mothers should not change their diet based on this single animal study, but may find it interesting as part of the broader conversation about how maternal nutrition affects baby health. People interested in probiotics and gut health may also find this relevant.

In the pig study, immune changes were detected within 4 hours of the bacterial challenge. If similar effects occur in humans, benefits would likely develop gradually during pregnancy and nursing, with the strongest effects appearing during stressful periods like weaning or introduction of new foods. Long-term studies would be needed to determine how long protective effects last.

Want to Apply This Research?

  • For pregnant or nursing users interested in probiotics: Track daily probiotic/prebiotic intake (type and amount), note any digestive changes, and monitor energy levels and immune health markers (like frequency of colds or infections). Record this weekly to identify patterns.
  • Users could add a daily probiotic-rich food or supplement to their diet during pregnancy or nursing, such as yogurt with live cultures, kefir, or a live yeast supplement. Start with small amounts and gradually increase while monitoring digestive comfort. Log this habit in the app to maintain consistency.
  • Create a long-term tracking system that monitors: (1) consistency of probiotic intake, (2) digestive health markers, (3) immune health indicators (illness frequency, duration, severity), and (4) energy and wellness ratings. Review monthly to assess whether the habit is being maintained and whether perceived health benefits are occurring. Share data with healthcare providers for personalized guidance.

This research was conducted in pigs and has not been tested in humans. The findings are preliminary and should not be used to make medical decisions for pregnant people, nursing mothers, or infants without consulting a healthcare provider. Live yeast supplements are not regulated the same way as medications and may not be appropriate for everyone. Pregnant and nursing individuals should discuss any dietary supplements with their doctor before use. This summary is for educational purposes only and does not constitute medical advice.