April 19, 2023


Selko Feed Additives: A study snapshot from ArMoR Health Livestock presentation 

An eFeedLink Exclusive Talk


During a presentation at the ArMoR Healthy Livestock event held at Wageningen University in the Netherlands, Selko, the feed additive brand of Nutreco, presented findings from a study that evaluated how science-based nutrition influences metabolites and gut maturation during the critical weaning stage.


Following the gathering, Tetske Hulshof, the lead of the research, remarked on key findings shared in the presentation.


What explains today's urgency in identifying and validating strategies to support piglets' gut health?


Tetske Hulshof: It has always been essential to keep piglets eating during the weaning phase to assure weight gain and proper development/maturation. Adequate feed intake also helps protect animals against diarrhea and other enteric challenges.


But strategies formerly relied on to manage gut health are being restricted in many regions. For example, in-feed antibiotics or antibiotic growth promoters were included in animal diets for many years in various parts of the globe. Similarly, feeding high levels of trace minerals was a common practice to support pigs' gut health. Today, producers are met with more restrictions when it comes to practices like feeding high levels of trace minerals.


Thus, we need new options, and science-based nutrition is one path to help steer young pigs' health and performance.


Blended feed additive research was presented at the ArMoR Health Livestock event. What role can these blends play in supporting the animal?


Tetske Hulshof: Blended feed additives have shown promise in steering and nurturing the maturation of piglets' digestive tracts.  But the blend requires careful attention to the selection of ingredients and the levels at which they are included.


In the case of the research presented at ArMoR, researchers looked at an additive blend combining precise amounts of specific organic acids, medium-chain fatty acids, slow release C12, butyrates and phenolic compounds that target gut health and animal development.


What made these ingredients of interest as scientists developed a blend?


Tetske Hulshof: These ingredients have demonstrated efficacy in supporting overall animal performance and limiting upset in the gut region. And as attention continues to focus on the role of the animal's microbiota, these blends are known to alter the microbiota to help increase the levels of Firmicutes and specifically the Lactobacilli genus while lowering harmful bacteria.


What did researchers study when evaluating the feed additive blend?


Tetske Hulshof: The study presented at the ArMoR Healthy Livestock gathering looked at how blended feed additives developed to support gut health may influence changes occurring inside the animal and the pathways that may be involved.


Understanding where feed additives prompt change within the animal's system and when they occur can help  inform producers' strategies to support animals in antibiotic-free production systems.


A more comprehensive understanding of a feed additive blend's mode of action can also improve precision when using the additive in the animal's diet.


How was the study designed and what did it track?

Tetske Hulshof: The study evaluated the mode of action in Presan®-FX, a blended feed ingredient that is made up of organic acids, medium-chain fatty acids, slow release C12, butyrates and phenolic compounds.

A total of 108 weaned piglets received one of two diets over the 14-day study. One group of piglets received a diet with the blended feed additive on top whilst the other group received a control diet. Researchers tracked piglets' body weight gain and feed intake.

In addition, piglets' blood and intestinal samples were collected pre-weaning and throughout the trial and these samples were examined to determine the presence of microbiota and metabolites.


What were the results of the study and the implications from findings?


Tetske Hulshof: Overall, the piglets that were fed the diet with the blended feed additive on-top had a similar feed intake to piglets on the control diet. But, despite the similar feed intake, the piglets receiving the feed additive had an improved average daily gain.


A change in fatty acid use and digestion is thought to explain the difference in weight gain. The added gain observed in pigs receiving the blended feed additive may indicate that piglets receiving the feed additive were better able to access the nutrition provided in their diets (Figure 1).


Figure 1 – Supporting gut health and development may have allowed piglets to get more nutrition from the same amount of feed as control group pigs.


Animals receiving the blended feed additive in their diets experienced internal responses from a range of metabolites as cholic acid, choline and taurine levels shifted. During the trial, cholic acid levels increased in samples collected from both plasma and the small intestine. But on days 7 and 14, the levels of both choline and taurine in plasma declined. These changes indicate a shift in the bile metabolism and potential increase in bile production. This action supports the development of a microbiome that is more tolerant to bile. (Figure 2).



Figure 2 – Changes to the expression of certain metabolites inform the production of acid in the gut.

What are the effects of higher levels of bile?
Tetske Hulshof: Higher levels of bile may improve nutrient digestion. Additionally, higher levels may support the growth of beneficial bacteria that deliver an antimicrobial effect.
And finally, the higher levels may help protect against the colonisation of pathogenic bacteria that can threaten gut function.
What additional findings were seen in piglets receiving diets supplemented with a blended feed additive?
Tetske Hulshof: The supplemented piglets had an increased indole-3-propionic acid (IPA) level in plasma compared to piglets that received the control diet. Higher IPA production helps support gut barrier function and is an indicator of a more mature microbiota.
Additionally, IPA and other metabolites play a role in regulating gut barrier function.
Considering activity at the intestinal level, the animals receiving the supplemented feed showed a higher abundance of lactobacillus in the small intestine. Again, these bacteria may support gut barrier function as they help with the transition of tryptophan into IPA.
Researchers also observed a decline in the variation of opportunistic bacterial species found. This observation suggests that a more stable microbiota population had been established earlier after weaning. Shifts in the bacterial population likely stemmed from changing conditions that supported the growth of lactobacillus and helped it out-compete other bacteria present in the gastrointestinal region.
Were there other findings of interest in the study?
Tetske Hulshof: Multiple elements were tracked during the study not just cholic acid, choline, taurine and IPA levels. However, changes in these areas were found during the data analysis. The alterations noted between the supplemented and control-group piglets were not surprising as the movement makes sense given past behavior of the feed additive use.
What was the final takeaway message for attendees at the ArMoR Livestock event?
Tetske Hulshof: The mode of action findings indicate that the blended feed additive can support piglet gut health, development and maturation in antibiotic-free production systems.
As producers are facing more restrictions on conventional interventions, feed additive blends can be an economically viable alternative. But the proper level and combination of ingredients is essential.
Thoughtfully selected ingredients delivered at the proper level in a blended feed additive are designed to support gut maturation and help maintain gut health and piglet growth and development.
Investments in research to understand the pathways influenced by the ingredients in feed additive blends help verify usage-based results and informs precise use of science-based nutrition.

- Selko Feed Additives