Oliveira, Maryane S. F., Jerubella J. Abelilla, Neil W. Jaworski, John K. Htoo, and Hans H. Stein. 2020. Crystalline amino acids do not influence calculated values for standardized ileal digestibility of amino acids in feed ingredients included in diets for pigs. Journal of Animal Science, 2020, Vol. 98, No. 11, 1–8.  doi:10.1093/jas/skaa333.

Sunflower meal, which is the co-product derived from sunflower seeds after oil extraction, has a high concentration of digestible amino acids (AA) and fiber. The nutritive value and quality of sunflower meal is partially dependent on the degree of dehulling, the variety of the sunflower, and the oil extraction process. Sunflower seeds are initially de-hulled and then partially de-oiled using a mechanial prepress procedure. A second de-oiling procedure is performed using a solvent extraction procedure or by usign a second mechanical expelling procedure. The prepress-solvent extraction procedure results in production of sunflower oil and sunflower meal that contains 1 to 3% oil, whereas the double-press procedure results in production of sunflower oil and a sunflower product that contains 5 to 10% residual oil and commonly is referred to as sunflower expellers. Some of the hulls may be added back to the sunflower meal or the sunflower expellers resulting in differences in concentrations of total dietary fiber among sources.

The apparent ileal digestibility and the standardized ileal digestibility (SID) of crude protein (CP) and AA in individual sources of partially de-hulled sunflower meal fed to pigs have been reported. However, there are no comparative values for the SID of AA in sunflower meal produced in different parts of the world, and it is not known if the SID of AA in sunflower meal are different from those in sunflower expellers. Therefore, the objective of the current study was to test the hypothesis that there is no difference in the SID of CP and AA in different sources of sunflower meal and sunflower expellers obtained from different countries.

Rodriguez, D. A., Su A Lee, and H. H. Stein. 2020. Nutrition Know-How: High-Shear Dry Soybean Expellers. Pork Magazine, On-line edition, Aug. 2020. Link to full text.

In most AA digestibility experiments collection bags are changed at least every 30 min and the collected ileal digesta are stored at –20 °C to prevent microbial degradation of proteins. Other attempts to reduce microbial activity in digesta include adding acids to collection bags to reduce the pH in ileal digesta. Acids may also be added to collection pitchers. However, in some experiments, no attempt to reduce pH is made because it is assumed that the rapid reduction in temperature after collection is sufficient to prevent microbial degradation of proteins.

To our knowledge, there is, however, no information about the necessity of adding acids to collected digesta and it is not known if values for apparent ileal digestibility (AID), basal endogenous losses of AA, or standardized ileal digestibility (SID) of AA are influenced by addition of acids to digesta. Therefore, the objective of this experiment was to test the null-hypothesis that values for AID, basal endogenous losses, and SID of AA are not influenced by addition of acids to ileal digesta collection bags or to collection pitchers.

McGhee, Molly L., and Hans. H. Stein. 2020. The apparent ileal digestibility and the apparent total tract digestibility of carbohydrates and energy in hybrid rye are different from some other cereal grains when fed to growing pigs. Journal of Animal Science, 2020, Vol. 98, No. 7, 1–10. doi:10.1093/jas/skaa218. Link to full text.

Several experiments were conducted to estimate Ca digestibility in different feed ingredients in the presence or absence of microbial phytase to allow formulation of diets for pigs to be based on standardized total tract digestible (STTD) Ca instead of total Ca. Thus, 4 experiments aimed at determining Ca requirements expressed as a ratio between STTD Ca and STTD P in pigs from 11 to 130 kg. A follow-up study was later conducted to validate those data and to evaluate the effect of using ratios that maximize growth performance on bone development because maximum bone ash requires more Ca than maximum growth performance. However, data indicate that STTD Ca to STTD P ratios to maximize Ca retention are greater than to maximize bone ash synthesis. The use of STTD Ca to STTD P ratios in diet formulation may result in a reduction in excess dietary Ca, which is beneficial because excess dietary Ca is detrimental to P digestibility and growth performance of pigs. Therefore, the objective of this experiment was to test the hypothesis that formulating diets for growing pigs based on a ratio between STTD Ca and STTD P instead of total Ca and STTD P does not decrease Ca retention, but increases P utilization.

Rundle, Carly M., Valeria Artuso-Ponte, and Hans H. Stein. 2020. Effects of isoquinoline alkaloids on apparent ileal digestibility of amino acids, acid hydrolyzed ether extract, and starch by young growing pigs fed corn-soybean meal diets. Transl. Anim. Sci. 2020.4:1-7. doi: 10.1093/tas/txaa054. Link to full text. 

Bakery meal consist of unsalable bread, breakfast cereals, cookies, pasta, and other foods that are no longer intended for human consumption. Bakery meal converts losses from the food industry into ingredients for the animal feed industry, thereby preventing food losses in the food chain. Wheat flour is the main ingredient in most bakery products, and this results in bakery meal containing high concentration of starch. Therefore, bakery meal is a potential sustainable feed ingredient that can be used in animal diets without competing with the food industry. However, research demonstrating the effect of bakery meal on growth performance for weanling pigs is limited. Therefore, an experiment was conducted to test the hypothesis that replacing corn with bakery meal will not influence growth performance of pigs.

Archs Toledo, J. L., Su A Lee, and H. H. Stein. 2020. Is the phosphorus in rye more digestible? Pork Magazine, April 8, 2020. Link to full text.