Rojas, O. J., Y. Liu, and H. H. Stein. 2014. Concentration of metabolizable energy and digestibility of energy, phosphorus, and amino acids in lemna protein concentrate fed to growing pigs. J. Anim. Sci. 92:5222-5229. Link to full text (.pdf)

Gutierrez, N. A., D. Y. Kil, Y. Liu, J. E. Pettigrew, and H. H. Stein. 2014. Effects of co-products from the corn-ethanol industry on body composition, retention of protein, lipids and energy, and on the net energy of diets fed to growing or finishing pigs. J. Sci. Food Agric. 94:3008-3016. Link to full text (.pdf)

Almeida, F. N., R. C. Sulabo, and H. H. Stein. 2014. Amino acid digestibility and concentration of digestible and metabolizable energy in a threonine biomass product fed to weanling pigs. J. Anim. Sci. 92:4540-4546. Link to full text (.pdf)

Liu, Y., M. Song, T. Maison, and H. H. Stein. 2014. Effects of protein concentration and heat treatment on concentration of digestible and metabolizable energy and on amino acid digestibility in four sources of canola meal fed to growing pigs. J. Anim. Sci. 92:4466-4477. Link to full text (.pdf)

Global production of rice is third in terms of total tonnage after corn and wheat. Rice is grown to produce polished white rice for human consumption. However, harvested rice, called paddy rice or rough rice, needs to be dehulled, which results in production of brown rice. The outer brown bran layer of brown rice, known as rice bran, also needs to be removed before polished white rice is produced. Approximately 20% of the paddy rice is hulls and the bran fraction is 8 to 10%, so only 70% of the paddy rice will become polished rice. Rice bran is high in fiber, and also contains about 15% crude protein and 14 to 20% fat. Rice bran can be fed as full fat rice bran or defatted rice bran. During milling of the rice, some kernels may get broken and cannot be used for human consumption. These broken kernels are known as broken rice or brewers rice and may also be used in animal feeding. Broken rice is high in starch and contains little fat, fiber, or protein.

Both rice bran and broken rice may be fed to pigs, but these ingredients are poorly characterized in terms of nutritional value. An experiment was, therefore, conducted to determine the standardized ileal digestibility (SID) of crude protein and amino acids in broken rice, two sources of full fat rice bran (FFRB), and defatted rice bran (DFRB) fed to growing pigs.

When evaluating the energy content of pig diets, producers and feed companies in the United States usually use the digestible energy (DE) and metabolizable energy (ME) systems. However, these systems do not take into account the heat produced by the animals during digestion, and thus the energy lost by pigs in the process of digesting and metabolizing the feed. Pigs fed diets high in fiber have greater feed intake, larger gastrointestinal tracts, and increased hindgut fermentation relative to pigs fed diets containing less fiber. Therefore, they might be expected to have greater heat production as well. As a result, the DE and ME systems may overestimate the energy value of fibrous feed ingredients. Net energy (NE) takes heat production into account, and thus may be a more accurate estimate of the energy available to the pig.

An experiment was conducted to test the hypothesis that increasing dietary fiber in diets fed to growing pigs will increase heat production and decrease net energy values.

Distillers dried grains with solubles (DDGS), a co-product of the ethanol industry, is an affordable source of energy and protein in pig diets. DDGS contains more gross energy than corn, but the energy is less digestible because of the high concentration of insoluble fiber in DDGS. If the fiber in DDGS could be made more soluble with pretreatment, its feed value would be improved.

An experiment was conducted to determine the effects of physical, chemical, and enzymatic pretreatments on the concentrations of digestible (DE) and metabolizable (ME) energy and on the apparent total tract digestibility (ATTD) of gross energy, organic matter, acid detergent fiber (ADF), and neutral (NDF) detergent fiber.

Soybean meal is the most common source of protein in swine diets in the United States. However, conventional soybean meal contains antinutritional factors such as antigenic proteins, oligosaccharides, lectins, and trypsin inhibitors that limit its use in diets fed to weanling pigs. Methods of processing soybean meal to remove antinutritional factors have been developed. These include enzyme treatment, fermentation, and the removal of soluble carbohydrates.

Like soybean meal, rapeseed products are usually not fed to weanling pigs due to the presence of glucosinolates and relatively high concentrations of fiber in these products. Previous research has shown that fermentation of soybean meal can reduce antinutritional factors and fiber concentrations. An experiment was conducted to determine the apparent total tract digestibility (ATTD) of energy and concentrations of digestible (DE) and metabolizable (ME) energy in four sources of processed soybean products, conventional soybean meal, conventional 00-rapeseed expellers, and in a fermented mixture of co-products including 00-rapeseed expellers, wheat bran, potato peel, and soy molasses.

Liu, Y., R. C. Sulabo, T. E. Sauber, and H. H. Stein. 2014. Different corn hybrids fed to growing pigs. I. Chemical composition, energy concentration, and digestibility of nutrients. J. Anim. Sci 92(E-Suppl. 2):667 (Abstr.) Link to abstract (.pdf)