Today sows are producing more total piglets born than they ever have historically. The average number of piglets born per litter in the US was approximately 11.5 pigs per litter in 2004 but is now closer to 15 piglets per litter (Pigchamp Benchmarking, 2020). As piglet litter size increases, the sow must allocate more resources to farrow those additional piglets and provide nutrients for the growing litter size. The addition of dietary fiber in gestation may play an important role in reducing farrowing time, reducing number of stillborn piglets, increasing sow intake during lactation, increasing the number of pigs weaned, and increasing litter weaning weight.
Fiber has not been clearly defined, nor has a recommendation been clearly outlined for pigs in any phase of production. The lack of information around fiber requirements in the diet may be due to the insufficient methodology that has historically been available to measure the indigestible fraction of the diet. Crude fiber (CF) underestimates the fiber levels in the diet by 70-80%. The neutral detergent fiber (NDF) is a standard measurement in the US swine industry, and although it more accurately depicts the fiber levels relative to CF, it still has limitations due to the potential to overestimate fiber by measuring other insoluble non-fiber fractions as well as the inability to capture the soluble fiber component. Today we can measure the individual monomeric sugar composition, including soluble and insoluble fractions via wet chemistry methods or more recently through near infrared (NIR). These components would be included in our more complete measurement for fiber, the total dietary fiber (TDF) (Figure 1) which includes insoluble non-starch polysaccharides (NSPi) and soluble non-starch polysaccharides (NSPs) plus lignin.
Figure 1. The Crude Fiber (CF), Neutral Detergent Fiber (NDF), and Total Dietary Fiber (TDF) of Feed Ingredients*
*Data represent the average of all feed ingredients included in internal AB Vista database.
The TDF is generally thought to dilute the feed and tie up nutrients bound to fiber, leading to a negative perception of its role in animal nutrition. However, the addition of TDF in the diet can potentially have positive outcomes for pigs. During gestation, the inclusion of TDF has a positive influence on sow performance parameters with more pigs being weaned and increased litter weaning weight (Table 1). In addition, the increase of TDF in gestation has been shown to reduce the number of still born piglets and increase piglet viability (Feyera et al, 2017). Sows conditioned or adapted to consume greater levels of TDF are also able to increase feed intake of sows during lactation (Quesnel et al., 2009). Furthermore, addition of fiber to gestating sow diets can modify sow behavior, increasing satiety and decreasing aggression which can be an important component in group pen gestation.
With more complete measurements of fiber and the ability to measure the various fiber fractions, fiber is getting more attention and thus research is focusing on defining future fiber recommendation. This recommendation will not just be limited to total dietary fiber, but soluble and insoluble fiber components and even further down to individual NSP fractions.
AB Vista has produced a new reference guide which provides nutritionists with an introduction to the benefits of moving from conventional fiber methods to total dietary fiber analysis using Near Infrared Reflectance (NIR) technology. To receive a copy of the guide or to get a better understanding of the fiber content in your finished feed, please contact NAM@abvista.com or your technical representative. In addition, AB Vista has launched a new fiber calculator which uses average values of raw materials to calculate the dietary fiber content of finished animal feed.
Read more about fiber in sow diets in Part 2 of the series.