Below is an article written by Diego Navarro, a PhD Swine Nutritionist, on the impact of fiber in nursery diets and how incorporating high-fiber ingredients into diets can improve and/or maintain production performance.
Fiber has traditionally been viewed as a negative component of the diet, particularly in early nursery. This perception stems from uncertainty surrounding the role of fiber in nutrition and health. The uncertainty is a consequence of an incomplete understanding of what fiber is, how it should be measured and what happens to it in the body. Advancements in fiber analysis has enabled nutritionists to effectively incorporate high-fiber ingredients into monogastric diets to improve or maintain production performance.  
Dietary fiber is ubiquitous and practically unavoidable in animal feed, but some ingredients are more fibrous than others. Cereal grains, oilseed meals and ethanol byproducts contain varying concentrations of fiber. Not only do their fiber contents vary, the types of fiber are also different. For example, the structure of arabinoxylans in wheat are more branched than the structure of arabinoxylans present in corn. Fiber is defined as indigestible carbohydrates or lignin from plant material that have physiological effects on humans and animals. It is considered indigestible because fiber cannot be broken down by enzymes produced by the body. However, digestibility trials indicate that some fiber fractions do in fact disappear from the digestive tract. This is because certain fiber fractions may be fermented by the gut microbiota.
How does it work?
Fiber reduces the available energy in the feed because fermentation is a less efficient source of energy for the animal. In addition, high levels of dietary fiber have been shown to reduce digestibility of energy, protein, and minerals in monogastric animals. These must be considered when formulating high-fiber byproducts (e.g. distillers dried grains, wheat middlings, sugar beet pulp, soy hulls, rice bran, etc.) into the diet. However, these ingredients may also contain factors that reduce performance, such as mycotoxins in distillers dried grains or β-conglycinin in soy hulls, that can easily be overlooked. 
We can use high-fiber ingredients to effectively limit feed intake in gestation, improve laxation in lactation, or simply to reduce the cost of the diet. Fiber supplementation in the nursery is used to address health challenges and improve stool consistency, but it is not a “plug and play” solution. There are a multitude of factors that contribute to post-weaning diarrhea and accurate diagnosis should be the first step in solving the problem before any intervention. Fiber should be viewed as an essential tool in a toolbox, not a cure. Does that mean that fiber should only be used in health challenged scenarios? No, insoluble fibers stimulate movement of digesta through the intestinal tract to prevent stasis and proliferation of pathogenic bacteria. Prebiotic carbohydrates may improve performance by aiding the maturation of the gut. The key is to know what fibers you are working with because not all will give you the same result.  
Read the full article HERE for more information on the effectiveness of fiber supplementation and it’s role in the future of animal production.
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