Personnel changes
Natalia Fanelli finished her internship and returned to Brazil to finish her bachelor's degree.
After her work in our lab as a visiting scholar in 2016, Laia Blavi returned to Barcelona to complete her Ph. D. Now, she is back with us as a postdoc. Trine Pedersen also returned to take a class; she will be here for six weeks.
New experiments
Diego Lopez started an experiment to determine SID of amino acids in rye.
Charmaine started a study of nitrogen balance in pigs fed high concentrations of copper.
Laia began two experiments. The first was on the effects of an enzyme and DFM combination on the growth performance and carcass characteristics of growing/finishing pigs fed four diets differing in nutrient density. The second was a dose titration of a probiotic, evaluating the effects on swine performance and gut microflora composition.
Kate started a study of digestibility of amino acid in distillers yeast, soy protein concentrate, and a threonine biomass fed to pigs.
Travel and visitors
Dr. Stein, along with all grad students and visiting scholars, travelled to Omaha for the ASAS Midwest Section Meeting March 13-15. Laia, Diego Navarro, Vanessa, John, and Gloria gave oral presentations, and Gloria also presented a poster.
We had a number of distinguished visitors this month. Dr. Lineke de Jong from Agrifirm visited March 16-17. Dr. Nathan Augspurger from JBS United also visited on March 17. On March 21, Dr. Paul Moughan of Massey University in New Zealand visited with graduate students and colleagues, and also gave a presentation about his work on improved protein nutrition in humans.
Beob Kim, a former postdoc in the Stein lab, visited for a few days in early April. Dr. Kim is a professor at Konkuk University in South Korea, but is currently on sabbatical in Louisville, KY. He gave presentations to the lab on four topics: a gross energy estimation system, a phosphorus digestibility equation, an animal allotment program, and a balanced Latin square designer. He was also here to work on projects that he began back when he was a postdoc:
I had a separate project that I was involved in back in 2009, before I left. Some experiments I initiated at that time--samples were collected but not analyzed yet. But I got an offer from Konkuk University so I left, went back home to Korea. So I was here to work on those analyses and write up the papers.
Many of those projects were related to corn DDGS. The first paper we published was on HP-DDG, a relatively new product at the time. After that we tested amino acid digestibility variability in DDGS sources.
The recent work was on methodology for amino acid experiments. Usually we have a 5+2 period. Why a 7 day period? Because a week is 7 days. This way, the farm workers only have to collect ileal samples on Wednesday and Thursday. But scientifically, do we need the 5 day adaptation period? We didn’t know. So we did daily digesta collection procedures for 9 days. Also we're working on comparing marker methods. So we used chromium and titanium as markers, and we also used celite, which is an acid insoluble ash, and we tested digestibility differences.
Recently, we had two papers published in JAS that are also on methodology and ileal digestibility. Right now, at the farm, they feed at 8am, then they start collection from 8 in the morning until 4 or 5 in the afternoon. Now, why do they have to collect 8 or 9 hours? There's almost nothing the first couple of hours. And so what we designed was to collect samples at 2-hour intervals. So 8-10, 10-12, 12-2, 2-4, 4-6, like that. And then using those independent samples, we calculated the digestibility values. And we concluded that we don't have to collect all day! We can probably collect 10-3, or 10-2, 10-4, that should be more than good enough.
Publications
Jaworski, N. W. and H. H. Stein. 2017. Disappearance of nutrients and energy in the stomach and small intestine, cecum, and colon of pigs fed corn-soybean meal diets containing distillers dried grains with solubles, wheat middlings, or soybean hulls. J. Anim. Sci. 95:727-739.
Sotak-Peper, K. M., J. C. González-Vega, and H. H. Stein. 2017. Amino acid digestibility in soybean meal sourced from different regions of the United States and fed to pigs. J. Anim. Sci. 95:771-778.
Kim, B. G., Y. Liu, and H. H. Stein. 2017. Effects of ileal digesta collection time on standardized ileal digestibility of amino acids in corn, soybean meal, and distiller’s dried grains with solubles fed to growing pigs. J. Anim. Sci. 95:789-798.
Casas, G. A., C. Huang, and H. H. Stein. 2017. Nutritional value of soy protein concentrate ground to different particle sizes and fed to pigs. J. Anim. Sci. 95:827-836.
Blavi, L., Sola-Oriol, D. Pérez, J. F., and H. H. Stein. 2017. Effects of zinc oxide and microbial phytase on digestibility of calcium and phosphorus in maize-based diets fed to growing pigs. J. Anim. Sci. 95:847-854.
Long, C. J., H. H. Stein, and T. L. Felix. 2017. Effects of exogenous phytase supplementation and dietary phosphorus concentration on metabolism and digestibility of beef cattle. J. Anim. Sci. 95(Suppl. 5):52 (Abstr.)
Lowell, J. E., B. M. Bohrer, K. B. Wilson, M. F. Overholt, B. N. Harsh, H. H. Stein, A. C. Dilger, and D. D. Boler. 2017. Fresh belly characteristics and commercial bacon slicing yield in growing-finishing pigs fed an antibiotic-free diet or a diet supplemented with a natural antimicrobial. J. Anim. Sci. 95(Suppl. 5):65 (Abstr.)
Casas, G. A. and H. H. Stein. 2017. Effects of feeding level and physiological stage on digestibility of gross energy and nutrients and concentration of digestible and metabolizable energy in full fat rice bran and defatted rice bran fed to gestating sows and growing gilts. J. Anim. Sci. 95(Suppl. 5):78 (Abstr.)
Blavi, L., D. Solà-Oriol, J. F. Pérez, and H. H. Stein. 2017. Effects of zinc oxide and microbial phytase on standardized total tract digestibility of calcium in maize-based diets fed to growing pigs. J. Anim. Sci. 95(Suppl. 5):85 (Abstr.)
Navarro, D. M. D. L., E. M. A. M. Bruininx, L. de Jong, and H. H. Stein. 2017. Chemical composition and physicochemical characteristics of feed ingredients and effects on in vitro ileal and total tract digestibility of dry matter. J. Anim. Sci. 95(Suppl. 5):89-90 (Abstr.)
Navarro, D. M. D. L., E. M. A. M. Bruininx, L. de Jong, and H. H. Stein. 2017. Effects of physicochemical characteristics of feed ingredients on total tract digestibility of dry matter, energy, fiber, and protein by growing pigs. J. Anim. Sci. 95(Suppl. 5):90 (Abstr.)
Lagos, L. V. and H. H. Stein. 2017. Chemical composition and amino acid digestibility of soybean meal produced in the United States, China, Argentina, Brazil, or India. J. Anim. Sci. 95(Suppl. 5):93 (Abstr.)
Yoder, A. D., M. B. Muckey, C. R. Stark, H. H. Stein, and C. K. Jones. 2017. Determining starch gelatinization from grains collected at various locations within the extrusion process. J. Anim. Sci. 95(Suppl. 5):129 (Abstr.)
Mathai, J. K., H. L. Spangler, H. H. Stein, and K. J. Touchette. 2017. Effects of high neutral detergent fiber diets on the nitrogen balance of pigs fed threonine-limited diets. J. Anim. Sci. 95(Suppl. 5):136 (Abstr.)
Walsh, M. C., L. Payling, I. H. Kim, and H. H. Stein. 2017. Effects of a multistrain Bacillus spp. direct-fed microbial and protease combination at different doses on apparent ileal and total tract digestibility of nutrients in growing pigs fed corn–soybean meal–based diets – A combined analysis of two studies. J. Anim. Sci. 95(Suppl. 5):141 (Abstr.)
Casas, G. A., C. Huang, and H. H. Stein. 2017. Effect of particle size of soy protein concentrate on amino acid digestibility and concentration of metabolizable energy and effects of soy protein concentrate on growth performance of weanling pigs. J. Anim. Sci. 95(Suppl. 5):148 (Abstr.)