Fiber is gaining interest in the antibiotic-free piglet feeding program. They are divided into two important categories: insoluble fiber acts on the gastrointestinal tract, creates peristalsis and promotes intestinal health.

The latter, fermented fiber, provides a substrate for beneficial bacteria in the lower intestinal segment. Both types of fiber need to be added in the right amount to the diet of piglets.

Fiber is insoluble but can ferment

Insoluble fiber does not react with yeast, however, they have their own important role. The main components of insoluble fiber include lignin, cellulose, and some types of hemicellulose. On the contrary, fermentable fiber can be easily dissolved in the intestinal juice, but the degree of increase in viscosity is uneven.

For example, pectin increases viscosity more than hemicelluloses, but promotes more bacterial yeast processes. Other fibers, such as gums, are not considered here because they are usually very low in common food ingredients.

The benefits of fermentable fiber

Fermentable fiber is an integral element of the diet of piglets, providing many important health benefits. This type of fiber consists of oligosaccharides, pectin and hemicellulose, which cannot be digested by piglets but is metabolized by intestinal bacteria in the large intestine.

Beneficial gut bacteria such as Bifidum and lactic acid-producing bacteria convert fiber into organic acids such as butyric, propionic and lactic acids. These acids have many important effects. They reduce pH in the intestines, prevent the growth of pathogenic bacteria, provide energy to piglets, and, in particular, butyric acid aids in the repair of intestinal damage.

Both fermented fiber and insoluble fiber are needed in the diet of piglets to improve their overall health and development.

The percentage of fiber present in soybean husks

Soybean husk, the outer part of the soybean seed is usually removed during the extraction of soybean oil. In the past, soybean husks were often discarded or used for ruminants and pregnant sows as an alternative feed source to wheat bran and other expensive sources of fiber.

Today, however, soybean husks are receiving special attention as it is a valuable source of fiber for domestic animals, especially piglets. Soybean husks contain about 70% insoluble fiber, including hemicelluloses and celluloses. The peculiarity is that they also contain a significant amount of pectin, about 10%, which ranks second only to beet pulp. This makes soybean husks a suitable source of pectin-rich fibers for feed ingredients.

 

The use of soybean husks also has advantages in terms of availability and convenience. Compared to beet pulp, soybean pods are available all year round and the price is competitive.

A new development in the use of soybean husks is to treat them with enzymes to increase the amount of fermentable fiber. While the exact process remains a trade secret, it’s thought that hemicellulose, an important ingredient in soybean pods, will ferment faster after being processed. This is important because hemicellulose also causes viscosity, which we want to avoid in the food of domestic animals. Enzymatically treated soybean husks have the potential to provide smarter fiber and aid in the creation of antibiotic-free feeds.

In particular, the use of enzyme-treated soybean husks can reduce protein fermentation indicators in the large intestine of pigs, improving their overall gut health. This is an important step forward in optimizing the diet of farmed animals and helping to improve production performance.

Soybean husks and bacterial protein fermentation

During digestion, excess proteins often drift into the upper part of the large intestine, where they can stimulate the growth of harmful bacteria. This not only increases the risk of disease but also contributes to the production of ammonia, a toxin that can cause damage to the intestinal lining.

A new study indicates that using enzyme-treated soybean husks significantly reduces bacterial protein fermentation. Branched fatty acid content decreased by 23%, from 1.7% to 1.3%, and indole content decreased by 59%. This not only helps to control excess crude protein, but also supports the formulation of modern piglet rations with a high percentage of soybeans.

Links between butyric acid and ZnO supplementation in animal feed

Currently, the trend of reducing the use of additives in animal feed is becoming more common. This not only helps to reduce production costs, but also satisfies consumers’ preference for “clean” food. “Clean” foods usually do not need to use many additives to overcome the effects of anti-nutritional factors. Instead, the focus is on using refined raw materials to improve the gut health of animals.

One potential option is to use soybean husks to supplement butyric acid. The synthesis of this acid from soybean husks in animals can help provide butyric efficiently, without increasing feed costs due to calculated fiber fermentation.

It is also possible to replace zinc oxide with fiber. If it is possible to control the overgrowth of microbes by balancing the right amount of fiber in the feed, then zinc oxide can be substituted properly.

With enzymatic treatment to increase fermentation fiber content, soybean husks can become an appropriate source of functional fiber for piglet feed. This marks an important advance in research, allowing for the replacement of traditional gut health control methods by being more friendly to pets and the environment.