Fat digestibility in pigs study looks at oils in soybeans, corn co-products

Jul 30, 2013

Pork producers need accurate information on the energy value of fat in feed ingredients to ensure that diets are formulated economically and in a way that maximizes pork fat quality. Researchers at the University of Illinois have determined the true ileal and total tract digestibility of fat in four corn co-products, as well as in full fat soybeans and corn oil.

Hans H. Stein, a professor of at U of I, led the team of researchers in the study in which they looked at four corn co-products: dried with solubles (DDGS), high-protein distillers dried grains (HP DDG), corn , and a high-oil corn that contained about 7 percent lipids. They also tested full-fat soybeans and extracted corn oil.

Three diets were formulated containing each source of oil, as well as a basal diet that contained no added fat. These diets were fed to cannulated pigs. The apparent ileal and total tract digestibility of lipids in each diet was calculated and a regression procedure was used to estimate endogenous losses and to calculate the true ileal digestibility and the true total tract digestibility of lipids.

"We observed that the digestibility of oil in soybeans is much greater than in the corn co-products. It appears that pigs can utilize that oil much more easily," Stein said.

He attributed this to differences in the way fat is stored in the ingredients. "In soybeans, you have almost 20 percent fat, and therefore a lot of that fat is just stored as regular , and relatively easy to get to. In the other ingredients, in particular the corn germ and the DDGS, some of the fat is encapsulated by fiber, which makes it more difficult for the enzymes to digest."

According to study results, the true ileal digestibility of corn oil was greatest at 95.4 percent. Among intact sources of fat, the fat in full-fat soybeans (85.2 percent) and HP DDG (76.5 percent) was the most digestible. Digestibility of fat was lowest in DDGS (62.1 percent), high-oil corn (53.0 percent), and corn germ (50.1 percent).

Corn oil also had the greatest true total tract digestibility at 94.3 percent. Full-fat soybeans had the next greatest digestibility at 79.7 percent. HP DDG was next at 70.2 percent. Finally, DDGS (51.9 percent), corn germ (43.9 percent), and high-oil corn (41.4 percent) had the lowest true total tract digestibility.

Stein said the results of the research were in agreement with several previous experiments indicating that the energy value of some ingredients was less than would be expected based on their content. "But now we have an explanation because we realize that pigs don't digest those lipids very well so it doesn't necessarily help that these products have higher concentrations of oil," he said.

"From a nutritional point of view, there would be a clear advantage if we could first extract the fat and then add it to the diet as corn oil rather than leave it in the ingredients. Whether such an approach would be economical would depend on the cost of extracting the oil from corn germ and other ingredients," Stein said.

Explore further: Saturated fats do not yield better bacon

More information: The study, "In growing pigs, the true ileal and total tract digestibility of acid hydrolyzed ether extract in extracted corn oil is greater than in intact sources of corn oil or soybean oil," was published in the Journal of Animal Science and is available at www.journalofanimalscience.org/content/91/2/755.full

add to favorites email to friend print save as pdf

Related Stories

Feeding corn germ to pigs does not affect growth performance

Apr 01, 2013

Inclusion of corn germ in swine diets can reduce diet costs, depending on the local cost of corn germ and other ingredients. Recent research conducted at the University of Illinois indicates that corn germ can be included ...

Research sheds light on fat digestibility in pigs

Mar 07, 2011

Producers and feed companies add fat to swine diets to increase energy, but recent research from the University of Illinois suggests that measurements currently used for fat digestibility need to be updated.

Saturated fats do not yield better bacon

May 28, 2013

A recent paper published in the Journal of Animal Science suggests producers may want to adjust pig diets when including distillers dried grains with solubles (DDGS). Some producers believe that feeding pigs saturated fats w ...

Helping pigs to digest phosphorus

Jul 17, 2012

Phosphorus is a vital nutrient for pig growth, but pigs do not always digest it well. Research conducted at the University of Illinois has determined how adding various levels of the enzyme phytase to the diet improves how ...

Using lysine estimates to detect heat damage in DDGS

Jan 14, 2013

Distillers dried grains with solubles (DDGS) are a good source of energy and protein in swine diets. However, they can be damaged by excessive heat during processing, compromising their nutritional value. University of Illinois ...

Replacing soybean meal in pig diets

Feb 28, 2013

Canola, cottonseed, and sunflower products can replace soybean meal in diets fed to pigs, but they contain less protein and energy. To determine if it makes economic sense to use them, producers need to know the concentrations ...

Recommended for you

User comments : 0

More news stories

Genetic code of the deadly tsetse fly unraveled

Mining the genome of the disease-transmitting tsetse fly, researchers have revealed the genetic adaptions that allow it to have such unique biology and transmit disease to both humans and animals.

Ocean microbes display remarkable genetic diversity

The smallest, most abundant marine microbe, Prochlorococcus, is a photosynthetic bacteria species essential to the marine ecosystem. An estimated billion billion billion of the single-cell creatures live i ...

Engineered E. coli produces high levels of D-ribose

D-ribose is a commercially important sugar used as a sweetener, a nutritional supplement, and as a starting compound for synthesizing riboflavin and several antiviral drugs. Genetic engineering of Escherichia co ...