Ronald Trotta
Regular Faculty
Professional Biography
Professional Biography
Assistant Professor, Ruminant Nutritional Physiology/Molecular Biology
Professional Experience
2024-Present Assistant Professor of Ruminant Nutritional Physiology/Molecular Biology
Department of Animal and Food Sciences
University of Kentucky, Lexington, KY
2023-2024 Postdoctoral Scholar
Department of Animal and Food Sciences
University of Kentucky, Lexington, KY
2020-2023 Graduate Research Assistant
Department of Animal and Food Sciences
University of Kentucky, Lexington, KY2018-2019
2018-2019 Graduate Research Assistant
Department of Animal Sciences
North Dakota State University, Fargo, ND
2017-2017 Undergraduate Research Assistant
Forage-Animal Production Research Unit
USDA-ARS, Lexington, KY
2014-2017 Animal and Food Sciences Student Worker
Department of Animal and Food Sciences
University of Kentucky, Lexington, KY
Research Program
Principal or co-investigator on over $1.4 million in research funding for projects relating to ruminant nutrition and physiology. Author or co-author on 26 peer-reviewed journal articles, 7 conference proceedings papers, and 16 abstracts.
Teaching Program
Teaching:
Primary course instructor for ASC 683: Protein Metabolism
Primary course instructor for ASC 689: Physiology of Nutrient Digestion and Absorption
Research Training and Mentorship:
Currently supervising the training of 1 postdoctoral scholar, 2 visiting scholars, 1 M.S. student, and 5 undergraduate students.
Scholars@UK
Association of serotonin and ergot alkaloids on tissue partitioning and contractile response of bovine blood vessels
Valente, E. E. L., Harmon, D. L., May, J., Ji, H., Trotta, R. J. & Klotz, J. L., Jan 2026, In: Current Research in Toxicology. 10, 100272.Research output: Contribution to journal › Article › peer-review
Endo-1,3-β-D-glucanase activity influences in vitro ruminal fermentation of diets varying in forage:concentrate
Seeforth, D. P. & Trotta, R. J., 2025, In: Journal of Animal Science. 103, skaf244.Research output: Contribution to journal › Article › peer-review
Timing of maternal nutrient restriction during mid-to late-gestation influences net umbilical uptake of glucose and amino acids in adolescent sheep
Trotta, R. J., Vasquez-Hidalgo, M. A., Smith, B. I., Reed, S. A., Govoni, K. E., Vonnahme, K. A. & Swanson, K. C., 2023, In: Journal of Animal Science. 101, skad383.Research output: Contribution to journal › Article › peer-review
Effects of dietary supplement sources on the rate and extent of in vitro Ruminal degradation of alfalfa-based diets for cattle
Trotta, R. J. & Swanson, K. C., 2020, In: Canadian Journal of Animal Science. 100, 2, p. 244-252 9 p.Research output: Contribution to journal › Article › peer-review
Prenatal and postnatal nutrition influence pancreatic and intestinal carbohydrase activities of ruminants
Trotta, R. J. & Swanson, K. C., Jan 2021, In: Animals. 11, 1, p. 1-12 12 p., 171.Research output: Contribution to journal › Review article › peer-review
Effects of nutrient restriction and melatonin supplementation from mid-to-late gestation on maternal and fetal small intestinal carbohydrase activities in sheep
Trotta, R. J., Lemley, C. O., Vonnahme, K. A. & Swanson, K. C., Jan 2021, In: Domestic Animal Endocrinology. 74, 106555.Research output: Contribution to journal › Article › peer-review
Influence of maternal nutrient restriction and rumen-protected arginine supplementation on post-ruminal digestive enzyme activity of lamb offspring
Trotta, R. J., Keomanivong, F. E., Peine, J. L., Caton, J. S. & Swanson, K. C., Nov 2020, In: Livestock Science. 241, 104246.Research output: Contribution to journal › Article › peer-review
Effects of ractopamine hydrochloride supplementation on feeding behavior, growth performance, and carcass characteristics of finishing steers
Trotta, R. J., Maddock Carlin, K. R. & Swanson, K. C., Jul 1 2019, In: Translational Animal Science. 3, 4, p. 1143-1152 10 p.Research output: Contribution to journal › Article › peer-review
Regulation of postruminal carbohydrase activities by dietary fructose in neonatal calves
Trotta, R. J. & Swanson, K. C., 2019, In: EAAP Scientific Series. 138, p. 239-240 2 p.Research output: Contribution to journal › Article › peer-review
Duodenal Infusions of Starch with Casein or Glutamic Acid Influence Pancreatic and Small Intestinal Carbohydrase Activities in Cattle
Trotta, R. J., Sitorski, L. G., Acharya, S., Brake, D. W. & Swanson, K. C., Apr 1 2020, In: Journal of Nutrition. 150, 4, p. 784-791 8 p.Research output: Contribution to journal › Article › peer-review
Disrupted one-carbon metabolism in heifers negatively affects their health and physiology
Crouse, M. S., Trotta, R. J., Freetly, H. C., Lindholm-Perry, A. K., Neville, B. W., Oliver, W. T., Hammer, C. J., Syring, J. G., King, L. E., Neville, T. L., Reynolds, L. P., Dahlen, C. R., Caton, J. S., Ward, A. K. & Cushman, R. A., 2024, In: Journal of Animal Science. 102, skae144.Research output: Contribution to journal › Article › peer-review
Influence of ractopamine hydrochloride supplementation on pancreatic digestive enzyme activity in finishing steers
Trotta, R. J., Maddock-Carlin, K. R. & Swanson, K. C., 2021, In: Canadian Journal of Animal Science. 101, 1, p. 191-195 5 p.Research output: Contribution to journal › Article › peer-review
Effects of Nutrient Restriction during Midgestation to Late Gestation on Maternal and Fetal Postruminal Carbohydrase Activities in Sheep
Trotta, R. J., Vasquez-Hidalgo, M. A., Vonnahme, K. A. & Swanson, K. C., Jan 2 2020, In: Journal of Animal Science. 98, 1, skz393.Research output: Contribution to journal › Article › peer-review
Influence of dietary fructose supplementation on visceral organ mass, carbohydrase activity, and mRNA expression of genes involved in small intestinal carbohydrate assimilation in neonatal calves
Trotta, R. J., Ward, A. K. & Swanson, K. C., Nov 2020, In: Journal of Dairy Science. 103, 11, p. 10060-10073 14 p.Research output: Contribution to journal › Article › peer-review
Whole stillage inclusion level influences in vitro fiber digestibility and ruminal fermentation of tall fescue hay
Ajayi, H. J., Davis, B. E., Lehmkuhler, J. W., Harmon, D. L., Jiang, Y. & Trotta, R. J., 2025, In: Journal of Animal Science. 103, skaf006.Research output: Contribution to journal › Article › peer-review
Influence of flake density and starch retrogradation on in vitro gas production kinetics, digestibility, and ruminal fermentation characteristics of steam-flaked corn
Trotta, R. J., Kreikemeier, K. K. & Harmon, D. L., 2024, In: Journal of Animal Science. 102, skae308.Research output: Contribution to journal › Article › peer-review
Influence of postruminal casein infusion and exogenous glucagon-like peptide 2 administration on the jejunal mucosal transcriptome in cattle
Trotta, R. J., Swanson, K. C., Klotz, J. L. & Harmon, D. L., Aug 1 2024, In: PLoS ONE. 19, 8, e0308983.Research output: Contribution to journal › Article › peer-review
Levodopa attenuates the feed intake reduction caused by ergot alkaloids in cattle
Valente, E. E. L., Klotz, J. L., Markmann, R. C., Trotta, R. J., Edwards, J. L., May, J. B. & Harmon, D. L., 2024, In: Journal of Animal Science. 102, skae078.Research output: Contribution to journal › Article › peer-review
Serotonin receptor-mediated vasorelaxation occurs primarily through 5-HT4 activation in bovine lateral saphenous vein
Trotta, R. J., Harmon, D. L. & Klotz, J. L., Jul 2024, In: Physiological Reports. 12, 13, e16128.Research output: Contribution to journal › Article › peer-review
Nutritional and Physiological Constraints Contributing to Limitations in Small Intestinal Starch Digestion and Glucose Absorption in Ruminants
Trotta, R. J., Harmon, D. L., Matthews, J. C. & Swanson, K. C., Mar 2022, In: Ruminants. 2, 1, p. 1-26 26 p.Research output: Contribution to journal › Review article › peer-review
Effects of Dose and Duration of PG25349 and its Derivatives on Methane Inhibition in Beef Cattle
Trotta, R. (PI), Harmon, D. (CoI) & McLeod, K. (CoI)
12/16/25 → 3/15/26
Project: Research project
ARS/FAPRU: Improving Sustainability of Forage-Based Production Systems
Trotta, R. (PI)
8/28/25 → 8/27/26
Project: Research project
Effects of exogenous phytase on small intestinal phosphorus disappearance in cattle
Trotta, R. (PI) & Harmon, D. (CoI)
9/1/25 → 3/31/27
Project: Research project
ARS/FAPRU: Improving Sustainability of Forage-Based Production Systems
Matthews, J. (PI), Bridges, P. (CoI), Ely, D. (CoI), Haan, N. (CoI), Harmon, D. (CoI), Hunt, A. (CoI), Ji, H. (CoI), McCulley, R. (CoI), McLeod, K. (CoI), Phillips, T. (CoI), Schardl, C. (CoI), Smith, S. (CoI), Suman, S. (CoI), Teutsch, C. (CoI), Trotta, R. (CoI), VanValin, K. (CoI) & Zhu, H. (CoI)
8/28/25 → 8/27/26
Project: Research project
Rapid evaluation of exogenous glucoamylases on blood glucose appearance from starch digestion in cattle
Trotta, R. (PI) & Harmon, D. (CoI)
5/29/25 → 3/31/27
Project: Research project
Year 2: Mitigation of Fescue Toxicosis with Soybeans
Trotta, R. (PI)
Kentucky Soybean Promotion Board
7/1/25 → 6/30/26
Project: Research project
Potential Amelioration Of Fescue Toxicosis By 5-Hydroxytryptophan In Beef Cattle
Trotta, R. (PI) & Harmon, D. (CoI)
National Institute of Food and Agriculture
8/1/24 → 7/31/26
Project: Research project
Mitigation of Fescue Toxicosis with Soybeans
Trotta, R. (PI)
Kentucky Soybean Promotion Board
7/1/24 → 6/30/25
Project: Research project
Mitigation of Sustained Ergot Alkaloid-Induced Vasoconstriction in Beef Cattle by Serotonin
Trotta, R. (PI) & Harmon, D. (CoI)
National Institute of Food and Agriculture
5/24/24 → 5/24/24
Project: Research project
