The physiological stage of pigs may influence total tract digestibility of nutrients because the digestibility of energy and some nutrients increases as body weight increases, but the impact of physiological stage may be greater for high-fiber diets than for diets with less concentration of fiber. Full fat rice bran (FFRB) and defatted rice bran (DFRB) are produced in the rice milling process and is available for animal feeding. However, because of the high concentration of dietary fiber, FFRB and DFRB may be better suited for diets fed to sows than for diets for weanling or growing pigs, but there is a lack of data on the digestibility of energy and nutrients in FFRB and DFRB fed to sows. Therefore, the objective of this experiment was to test the null-hypothesis that the apparent total tract digestibility (ATTD) of gross energy (GE), dry matter (DM), organic matter (OM), neutral detergent fiber (NDF), and P in a corn-soybean meal diet and in diets containing FFRB or DFRB is not different between lactating sows and gestating sows if both groups are allowed to consume their diet on an ad libitum basis.

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.