Espinosa, C. D., D. Velayudhan, Y. Dersjant-Li, J. Remus, H. H. Stein. 2021. Effect of phytase on mineral digestibility and growth performance of pigs fed diets with pharmacological levels of Zn. J. Anim. Sci. 99(Suppl. S3): 400-401. doi.org/10.1093/jas/skab235.727. Link to abstract.

Rapeseed is the second most produced oilseed in the world after soybean, and after the oil is extracted, a protein-rich meal is the resulting byproduct containing greater concentrations of sulfur amino acids (AA; i.e., Met and Cys) and Lys compared with legumes and cereal grains. Rapeseed proteins have great potential as a high-quality plant-based protein for humans due to their well-balanced AA profile, high metabolic utilization of protein, a protein digestibility corrected amino acid score (PDCAAS) similar to soy and milk proteins, and easily separable antinutritional factors. However, to our knowledge, digestible indispensable amino acid score (DIAAS) has not been determined for rapeseed protein isolate and the level of processing required to concentrate rapeseed into a protein isolate warrants further evaluation of its protein quality. Therefore, this experiment was conducted to test the hypothesis that heat treatment of rapeseed protein isolate will increase the digestibility of AA by growing pigs and result in a DIAAS that is comparable to soy and animal protein isolates.

Lee, S. A., M. R. Bedford, H. H. Stein. 2021. Comparative digestibility and retention of calcium and phosphorus in normal- and high-phytate diets fed to gestating sows and growing pigs. Animal Feed Science and Technology 280 (2021) 115084. doi.org/10.1016/j.anifeedsci.2021.115084. Link to full text.

Lee, Su A, Laia Blavi, Diego M. D. L. Navarro, and Hans H. Stein. 2021. Addition of hydrochloric acid to collection bags or collection containers did not change basal endogenous losses or ileal digestibility of amino acid in corn, soybean meal, or wheat middlings fed to growing pigs. Animal Bioscience Vol. 34, No. 10:1632-1642 October 2021. doi.org/10.5713/ab.20.0838.

Espinosa, Charmaine D., Maryane S. F. Oliveira, Deepak E. Velayudhan, Yueming Dersjant-Li, Hans H. Stein. 2021. Influence of a novel consensus bacterial 6-phytase variant on mineral digestibility and bone ash in young growing pigs fed diets with different concentrations of phytate-bound phosphorus. Journal of Animal Science, 2021, Vol. 99, No. 8, 1–12. doi.org/10.1093/jas/skab211.

Pharmacological levels of Zn (i.e., 2,000 to 3,000 mg/kg) is often included in diets for weanling pigs to prevent post-weaning diarrhea. However, pharmacological levels of Zn may reduce microbial phytase efficacy by chelating the phytate molecule, which subsequently prevents access for phytase.  However, it is possible that this effect can be reduced by adding more phytase to diets. Therefore, an experiment was conducted to test the hypothesis that inclusion of increasing levels of phytase increases pig growth performance and mineral digestibility in diets with 3,000 mg/kg of Zn.

Galkanda-Arachchige, Harsha S. C., Hans H. Stein, D. Allen Davis. 2021. Soybean meal sourced from Argentina, Brazil, China, India and USA as an ingredient in practical diets for Pacific white shrimp Litopenaeus vannamei. Aquaculture Nutrition. 2021;00:1–11. DOI: 10.1111/anu.13251. Link to full text.

Dried whey is often used as a source of lactose in diets for weanling pigs. Whey is a co-product from dairy processing plants that is generated after fat and protein in milk has been used to produce cheese. Whey powder is therefore, low in protein because the majority of the milk protein ends up in the cheese during processing. However, some of the cheese that is produced may not be suitable for human consumption, but can instead be used as a feed ingredient for pigs after being blended with other ingredients to improve flowability and handling.  One of the cheese co-products that is currently being marketed contains 40 to 50% crude protein and has a high digestibility of amino acids. There is, however, limited information about the energy value of cheese co-products fed to pigs although it is expected that because of the high concentration of fat in cheese, the energy value will also be high. Therefore, it was the objective of this experiment to test the hypothesis that digestibility of energy and concentrations of digestible energy (DE) and metabolizable energy (ME) in a cheese co-product is greater than that in fish meal and enzyme treated soybean meal when fed to weanling pigs.

Conventional breeding of corn has generated a new variety (i.e., high-oil corn; Byron Seeds LLC, Rockville, IN), which is believed to contain more oil and phosphorus than conventional corn. Because of the increased oil, it is possible that high-oil corn contains more digestible energy (DE) and metabolizable energy (ME) than conventional hybrids, but this hypothesis has not been experimentally verified. Inclusion of microbial phytase in diets for pigs usually improves digestibility of P because phytase hydrolyzes the ester bond that binds P to the phytate molecule in corn. However, there are at this point no data for effects of adding phytase to diets containing high-oil corn and no data to demonstrate the nutritional value of high-oil corn. Therefore, an experiment was conducted to test the hypothesis that the standardized total tract digestibility (STTD) of P, as well as concentrations of DE and ME in high-oil corn are greater than in conventional corn. The second hypothesis was that inclusion of microbial phytase to diets improves the STTD of P in corn sources.