Cristobal, Minoy A., Carl M. M. Parsons, Hans H. Stein. 2023. Concentrations of Digestible and Metabolizable Energy, Ileal Digestibility of Amino Acids, and Digestibility of Phosphorus in a New Variety of Soybeans Fed to Growing Pigs. J. Anim. Sci. Volume 101, Issue Supplement 2, Pages 51 - 52, doi.org/10.1093/jas/skad341.056. Link to abstract.

Protein quality has relied on methods such as PDCAAS. However, the Food and Agriculture Organization has proposed a new method called DIAAS to better assess protein quality in human foods using the pig as a model. This shift is crucial, not only for optimizing diets, but also for understanding the nutritional value of protein-rich foods. According to the DIAAS method, protein claims can only be made for foods with a score above 75. In general, animal-based foods are considered high quality proteins with score above 75 or 100, being, in most cases, complete proteins that can complement lower quality proteins such as plant-based proteins. Meats, eggs, and fish are examples of high quality proteins, however, salmon proteins are also available, and use of by-products in human consumption has been increasing due to their nutritional value and versatility. Novel sources of salmon proteins such as salmon hydrolysate that may be used in human nutrition have been developed. Salmon hydrolysate proteins contain more than 68% crude protein (CP) and are highly digestible food ingredients, but limited information demonstrating the protein quality of these products is available. Therefore, the objectives of this study were to determine the standardized ileal digestibility (SID) of amino acids (AA) and the digestible indispensable amino acid score (DIAAS) for salmon proteins when fed to growing pigs.

California is a leading producer of pistachios in the United States and globally and it is estimated that annual production will reach 2.08 billion pounds in 2031. As a result, about 31.2 million pounds of shells will be produced after the nuts are processed for human consumption. Pistachio shells have been viewed as a waste product and are frequently disposed of using ecologically friendly practices. However, it is possible that pistachio shell powder can be used as a high fiber ingredient for swine. Specifically, gestating sows may benefit from the high fiber concentration in pistachio shell powder because this may increase satiety and reduce stress. However, at this time, there is no information about the nutritional value of pistachio shell powder when fed to sows. Therefore, an experiment was conducted to test the hypothesis that apparent total tract digestibility (ATTD) of gross energy (GE) and concentrations of digestible energy (DE) and metabolizable energy (ME) in pistachio shell powder are not different from those in soybean hulls when fed to gestating sows. The second hypothesis was that the ATTD of GE and DE in pistachio shell powder are not different from those in soybean hulls when fed to lactating sows.

Lee, Su A, L. Vanessa Lagos, Laura A. Merriman, and Hans H. Stein. 2023. Digestibility of calcium in calcium-containing ingredients and requirements for digestible calcium by growing pigs. Journal of Animal Science, 101, 1–13. doi.org/10.1093/jas/skad328. Link to full text.

It is important that the digestibility of Ca in Ca sources is known to formulate diets based on values for digestible Ca rather than total Ca. Only a small amount of the Ca required by pigs is provided by plant-based ingredients and supplementation of Ca from Ca phosphates and Ca carbonate, is usually required to meet the requirement by pigs. In addition, use of microbial phytase increases Ca digestibility in Ca carbonate, which is one of the major sources of Ca in pig diets.

Differences in Ca digestibility in 4 sources of Ca carbonate produced in the United States have been observed, but it is unknown if there are differences in the ATTD of Ca in calcium carbonate sources produced outside the United States. Therefore, the objective of this experiment was to test the hypothesis that there are differences in the apparent total tract digestibility (ATTD) and standardized total tract digestibility (STTD) of Ca and in the response to microbial phytase among 20 sources of Ca carbonate obtained from different parts of the world.

Fanelli, Natalia dos Santos, Juliana Carolina Florencio Ravagnani Martins, and Hans Henrik Stein. 2023. Digestible indispensable amino acid scores (DIAAS) for egg and plant proteins. International Symposium Dietary Protein for Human Health. Utrecht, The Netherlands Sep 2023. Pag 74. Link to Abstract.

Stein, H. H. 2023. Non-traditional feed ingredients in diets for pigs. Book of abstracts of the 74th annual meeting of the European Federation of Animal Science. Aug. 26 to Sep. 1, 2023. Lyon, France. Page 286. Link to abstract.

Protein malnutrition is a serious problem in both underdeveloped countries and the U.S., where many children and elderly people don't get enough protein. To determine the quality of food proteins, experts use a method called digestible indispensable amino acid score (DIAAS), which measures how well the body can digest the amino acids in a food item. The FAO recommended this method in 2011. According to the DIAAS method, protein claims can only be made for foods with a score above 75. Eggs are rich in protein and essential amino acids needed for muscle development and bodily functions. However, it's important to consider how eggs are cooked, as different methods can affect the availability of amino acids. Eggs are often eaten with other foods, and it's believed that the high-quality protein in eggs can make up for the lower quality of protein in plant ingredients when eaten together, but more research is needed to confirm this. Therefore, the objectives of this experiment were to determine DIAAS for eggs cooked in different forms and in traditional egg-style combinations with breads or hash brown, and test the hypothesis that protein quality in eggs can compensate for the low protein quality of plant-based ingredients and that DIAAS in different combined meals is additive.

Espinosa, C. D., J. D. Ward, and H. H. Stein. 2023. Increasing phosphorus digestibility in novel corn fermented products. National Hog Farmer, July 27, 2023. Link to full text.