ADM PremiDexTM Has Beneficial Impact on
Swine Performance and Gut Microbial Population


PremiDex, a modified starch, is a proprietary feed ingredient manufactured by ADM. ADM swine research trials have shown nursery pigs fed PremiDex responded with an average daily gain improvement of 2.7% and feed efficiency improvement of 3.5% for pigs reared under conditions of low stress and minimal pathogen challenge. PremiDex may provide greater benefits when fed to pathogen-challenged pigs or pigs under stress conditions. MOMENTUM® nursery products from ADM Animal Nutrition will now contain PremiDex as
a research-proven and beneficial feed ingredient.

Identifying innovative proprietary technologies to improve pig performance while providing an economic advantage continue to be of highest priority for the ADM Animal Nutrition swine research team. ADM PremiDex (the trade name for ADM dextrin) is a modified starch derived from a patented manufacturing process initially developed for industrial applications. Innovative research applications were sought for the possible use of dextrin as a prebiotic in swine diets. ADM swine research has shown PremiDex to be an effective feed additive that can have positive benefits on swine performance and can favorably alter swine intestinal microorganism populations. The application of a dextrin-use patent for livestock, poultry, and aquaculture feeds is the result of ADM's innovative research.


Also see technical bulletin - Proving Its Worth in Swine Grow-Finish Diets

Role of Microorganisms in Intestinal Health
Many different microorganisms colonize the gastrointestinal tract (GIT), beginning in the mouth and continuing throughout the entire GIT. In fact, the GIT can be thought of as the largest organ in the body, housing well over 100 trillion microorganisms for every gram of intestinal content. It should be no surprise that fluctuations in the microbial population can have beneficial or adverse effects on overall intestinal and body health. In normal non-disease conditions, beneficial organisms dominate the population and provide advantages for digestion and absorption of feedstuffs, health and immunity of the intestine, and overall body health. In disease-challenged animals, these populations shift toward an increase in pathogenic organisms that can disrupt normal processes, often evident as diarrhea, decreased performance, and even death. Microbial population balance is critical in maintaining healthy animals. Feed additives, such as prebiotics, may be fed to animals to help alter the balance of microbial populations by helping provide an environment that can selectively increase beneficial organisms in the GIT. As a result, some prebiotics may foster intestinal health and subsequent performance.

Overview of Prebiotics
A prebiotic has been defined as a non-digestible carbohydrate that beneficially affects the host animal by selectively stimulating the growth and/or activity of one or a limited number of bacteria in the colon. As bacteria have evolved to gain a competitive edge in their environment, certain commensal (beneficial) bacteria such as Lactobacilli and Bifidobacteria have developed the ability to use certain sugars that other bacteria cannot utilize for their growth and development. The competition for nutrients in the intestine is intense. Increasing the commensal population can be achieved by supplying a source of nutrients only available to commensals. In this competitive environment, when one bacterial population increases, it deters growth of another population. This increase in the number of "good" bacteria is usually detrimental to pathogenic bacteria. An analogy would be the crowding out of weeds when cultivated plants are thriving. This means commensals outnumber pathogens to an even greater degree, so that it should require more pathogens to cause disease than it would have without the prebiotic. This becomes even more important when conditions are less than ideal in the animal's environment.

Interaction of Prebiotics with Other Feed Additives
The use of prebiotics can be synergistic with many other feed additives including antibiotics, mannan oligosaccharides (pathogen binders), direct-fed microbials, and acidifiers. These feed additives usually have different modes of action compared to a prebiotic. The structure of prebiotic sugars prevents digestive enzymes in the stomach and small intestine from breaking them down. This enables commensal organisms in the large intestine to directly utilize prebiotic sugars. Prebiotics can be especially beneficial in conjunction with mannan oligosaccharides (MOS). Mannan oligosaccharides, such as CitriStim®, have been shown to act as pathogen binders to remove pathogens out of the GIT; whereas, a prebiotic may promote growth of beneficial bacteria in the colon. Therefore, using both additives in a nursery diet should work synergistically to favorably impact the gut microbial population. University of Illinois research has shown that including a MOS and prebiotic in canine diets had additive effects on immunity, gut health, and manure odor.

ADM PremiDex Basics
Dextrins are starch hydrolysis products produced via a dry roasting process using starch alone or with trace levels of an acid catalyst. ADM has developed a patented process to manufacture a dextrin product (PremiDex) from grain starch. This manufacturing process (called dextrinization) is designed to intentionally re-arrange grain starch molecules to convert a portion of normal alpha-1,4-glucose linkages to random 1,2-, 1,3-, and 1,4- alpha and beta linkages.

Starch consists primarily of alpha (1 4) glucosidic linkage and is commonly used as an energy source in swine diets. The pig's digestive enzymes, amylase and glucoamylase, can break down the glucose bond linkage of starch in the stomach and small intestine, which releases energy for the animal to use. However, the randomization of glucose linkages makes PremiDex resistant to digestion by enzymes typically released in the stomach and small intestine. Thus, PremiDex passes into the large intestine where it provides food for ?good? bacteria. The manufacturing process only randomizes a portion of the starch linkages. This portion of randomized starch is referred to as resistant starch. The higher the percentage of resistant starch contained in dextrins, the more effective dextrins will be as a prebiotic. Dextrin can be further treated by enzymes to manufacture a different product that contains even more resistant starch. This ADM product is marketed under the trade name Fibersol-2®* as a food-grade ingredient for humans.

ADM PremiDex Research

In-vitro Gas Production
ADM research evaluated the fermentation capacity of PremiDex in vitro using a ruminant gas-production monitoring system. Volume of gas production from this monitoring system is an indication of the degree of rumen fermentation. The lower the amount of gas produced from a product, the more it can escape the rumen and reach the large intestine. Regular starch and PremiDex samples were fermented over a 24-hour period.


The volume of gas produced by each product was measured at intervals over the 24-hour period. PremiDex had less gas production than regular starch (Figure 1). This clearly indicates that PremiDex is less fermentable (digestible) compared to regular starch.

This does provide an indication that PremiDex could reach a pig's large intestine where it could serve as a prebiotic for healthy bacteria.

Impact on Gut Microbial Populations

Most prebiotics, including PremiDex, are thought to selectively promote growth of beneficial bacteria in the large intestine (primarily in the colon). A swine grow-finish trial (S04201) was conducted at the ADM Animal Nutrition Research Center to evaluate the effects of PremiDex on gut microbial populations. Pigs (45.4 lb initial weight) were fed diets with or without PremiDex. At the end of the 101-day study, fecal samples from seven pigs per treatment were taken and sent to the University of Missouri for microbial population analysis. The samples from the pigs that were fed diets containing PremiDex had healthy Lactobacilli bacteria counts that were 41.4% higher than samples from pigs fed diets without PremiDex (Figure 2). The potentially harmful E. coli bacteria counts in the pigs fed diets containing PremiDex were 33.6% lower than in the samples collected from pigs fed diets without PremiDex. These fecal microbial population changes indicated a change in the numbers of both "good" bacteria (increased number) and "bad" bacteria (reduced number), which could translate to better pig growth performance.

Swine Nursery Trials
A series of swine nursery trials conducted by ADM have shown consistent improvement in feed efficiency and growth performance with the inclusion of PremiDex in nursery diets. A titration study was conducted to evaluate the optimal inclusion level of PremiDex in nursery diets (S04126). One hundred fifty pigs (9.15 lb initial weight) were split into six pens per treatment in this study. Pigs were fed one of five diets that contained different amounts of PremiDex, from none to a very high amount. A four-phase feeding program (7, 7, 14, and 14 days, respectively) was fed to test pigs. The antibiotic Mecadox®* was used throughout the trial. At the end of each phase, pigs and feeders were weighed. Daily gain increased when low levels of PremiDex were included in the diets (Table 1). However, daily gain was similar between pigs fed very high levels of PremiDex and those that did not receive PremiDex, suggesting the addition of too much PremiDex in diets was not beneficial to nursery pigs. Pigs fed the medium level of PremiDex were almost two lb heavier compared to pigs that did not receive PremiDex.



In comparison to no PremiDex, adding any level of PremiDex significantly improved overall feed efficiency in this study. Feed efficiency was better for low to high levels of dietary PremiDex than a very high level of PremiDex, again suggesting that addition of too much PremiDex may not be beneficial. The improved feed efficiency observed in this study appeared to result from improved daily gain and somewhat reduced feed intake. This may be due to the change in bacteria counts that was observed in the previously referenced research trial. Healthy pigs use fewer nutrients from feed for disease-related metabolism leaving more nutrients for normal growth.


PremiDex-fed pigs had better feed efficiency. The feed efficiency improvement was also observed in three other nursery studies (Table 2). These four nursery studies have shown an average daily gain improvement of 2.7% and feed efficiency improvement of 3.5% for pigs fed PremiDex-containing diets compared with pigs that did not receive PremiDex. These positive performance improvements were observed in nursery pigs reared under conditions of low stress and minimal pathogen challenge. ADM PremiDex may provide greater benefits when fed to pathogen-challenged pigs or pigs under stress conditions.



Swine Grow-Finish Trial
A grow-finish study was conducted to evaluate whether PremiDex could improve performance of grow-finish pigs in the absence of an antibiotic in the diets. In this ADM study, 70 pigs (45.4 lb initial weight) were housed in 14 pens, with five pigs per pen. Pigs were assigned to one of two treatments:

  • Control diet

  • Control diet plus PremiDex

A 101-day, five-phase feeding program was adopted. Adding PremiDex resulted in better gain (6.2%), which was statistically significant (P < 0.05; Figure 3) and meant 8.1 lb heavier weight at the end of the 101-day study (246.4 versus 254.5 lb). Adding PremiDex had no significant effects on feed intake. As a result, pigs fed PremiDex-containing diets tended to have better feed efficiency (P < 0.15; Figure 4). Fecal microbial population from pigs on this test was found to be favorably altered by use of PremiDex (reported in Figure 2). Collectively, these data have demonstrated that PremiDex addition had a positive impact on growth performance, which may have been the result of more favorable gut microbial populations.



ADM PremiDex, a proprietary feed ingredient, is manufactured using a patented process. ADM swine research has demonstrated that PremiDex influences gut microbial population by increasing beneficial bacteria, i.e. Lactobacilli, and decreasing pathogenic bacteria, i.e. E. coli. Several swine nursery trials have shown that PremiDex-fed pigs responded with a growth improvement of 2.7%, and feed was converted more efficiently (3.5%). ADM's innovative idea to use PremiDex in animal feeds based on research documented swine performance benefits and favorable changes in gut microbial populations, has led to the filing of a dextrin-use patent for its applications in livestock, poultry, and aquaculture feeds. MOMENTUM® nursery products from ADM Animal Nutrition will now contain PremiDex as a research-proven and beneficial feed additive. Reference available upon request.


Also see technical bulletin - Proving Its Worth in Swine Grow-Finish Diets

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ADM Animal Nutrition, a division of Archer Daniels Midland Company