Mathai, J. K., J. K. Htoo, M. Wiltafsky, and H. H. Stein. 2018. Effects of various heat treatments on concentrations of digestible and metabolizable energy and on amino acid digestibility in soybean meal fed to growing pigs. J. Anim. Sci. 96(Suppl. 2):25-26 (Abstr.) Link to abstract (.pdf)

Fiber in feed ingredients used in diets for pigs is mainly used for energy, which is synthesized by microbes in the hindgut of the pig and absorbed in the form of short chained fatty acids. To estimate the energy that a pig can obtain in a particular fibrous ingredient, a digestibility experiment is usually conducted and the digestible energy (DE) and the metabolizable energy (ME) in the ingredient is determined. However, it is not known if the obtained DE and ME values are accurate for all inclusion rates of the feed ingredient in diets.

There are two reasons that differing inclusion rates of high fiber ingredients in diets fed to pigs might result in variable DE and ME values. Because energy from dietary fiber is obtained via hindgut fermentation, there may be a saturation point in the fermentation capacity in the hindgut of growing pigs. In addition, increasing dietary fiber increases the passage rate of feed through the digestive tract and thus reduces time for fermentation. However, it is not known if these potential issues affect the DE and ME in fibrous ingredients fed to pigs. An experiment was conducted to determine effects of inclusion rate of four commonly used high fiber dietary ingredients on the concentration of DE and ME by growing pigs.

In recent years, ethanol plants have begun extracting more oil from the solubles left over after fermentation. The resulting low oil distillers dried grains with solubles (DDGS) contain less digestible energy (DE) and metabolizable energy (ME) than traditional DDGS.

The fat content of the diet affects the digestibility of energy and nutrients. Because the production of low oil DDGS is a relatively new development, it has not been established that digestibility values are the same across suppliers. Therefore, an experiment was conducted to measure the apparent total tract digestibility (ATTD) of neutral detergent fiber (NDF) and the concentration of DE and ME among DDGS samples from different suppliers.

Distillers dried grains with solubles, or DDGS, is a co-product from the dry-grind ethanol production. It is increasingly in demand for use in livestock feeding, including diets fed to pigs. Conventional DDGS (DDGS-CV) contains approximately 27% crude protein. A high protein DDGS (DDGS-HP) product, containing 38 to 40% crude protein, has recently been developed by Lincolnway Energy by using front end separation that allows for fractionation of the corn kernel before it is fermented. The nutritional value for pigs of the resulting  DDGS-HP has, however, not yet been fully described.

Therefore, two experiments were conducted. The objective of the first experiment was to determine the concentrations of digestible energy (DE) and metabolizable energy (ME) and the apparent total tract digestibility (ATTD) of energy in DDGS-HP and DDGS-CV fed to growing pigs. In the second experiment, the standardized ileal digestibility (SID) of crude protein and amino acids in DDGS-CV and DDGS-HP were compared.

Casas, G. A. and H. H. Stein. 2017. Effects of feeding level and physiological stage on digestibility of gross energy and nutrients and concentration of digestible and metabolizable energy in full fat rice bran and defatted rice bran fed to gestating sows and growing gilts. J. Anim. Sci. 95(Suppl. 5):78 (Abstr.) Link to abstract (.pdf)