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Don Llewellyn, Livestock Extension Specialist


“Innovation rather than Renovation”–Producers and animals scientists do a lot of things very well. It is imperative that we enhance what we do well by providing producers with timely research-based information geared toward making livestock systems work better.


Focusing on three key components related to profitability and long-term viability of beef cattle operations:

  • Beef cow nutrition/reproduction–utilize effective nutritional management to maximimize the number of cows bred, and healthy calves born and marketed per cow exposed during the breeding season.
  • Livestock production, safety, and quality–This program includes providing producers the knowledge to keep cows and calves healthy throughout all stages of production.  In addition, Beef Quality Assurance (BQA) and Youth Pork Quality (PQA) Plus Assurance Training, along with proper animal handling programming helps insure safe and wholesome meat products for the consumer.
  • Management systems–Optimizing the use of available forages, protecting natural resources, and exploring the utilization of alternative feeds, forages, and supplements with a focus on reducing costs and increasing producer’s profits.


Llewellyn, D. A., R. Sero, E. Walker, J. S. Neibergs, J. P. Driver, and J. Smith. 2016. A successful youth beef exhibitor program:  Reviewing history, industry milestones, education, and 35 years of carcass excellence.  J. of NACAA.  Available at:

Llewellyn, D. A., and T. T Marston. 2016. Case Study:  Influence of fall liquid protein supplementation on performance of beef cows gazing native range.  J. of NACAA.  Available at:    

Llewellyn, D. A., G. Rohwer, O.S. Norberg, E. Kimura, J.S. Neibergs, and S.C. Fransen. 2015. Case Study:  Evaluating farm processed canola and camelina meals as protein supplements for beef cattle.  J. of NACAA, 8(2), available online at

Llewellyn, D. A., E. A. K. Schlickau, T. T. Marston, K. W. Harborth, R. M. Breiner, J. A. Unruh, and M. E. Dikeman. 2013. Influence of early weaning beef cows on the performance of male progeny and the need for winter protein supplementation. Agricultural Sciences 4(12):701-708.

Llewellyn, D. A. 2013. Finding first-year success in Extension:  Navigating stakeholder needs and institutional expectations.  J. Human Sci. Ext. 1(1):115-124.

Llewellyn, D. A., T. T. Marston, K. L. Teutemacher, J. J. Higgins, and T.  Melgarejo. 2010. Evaluation of low molecular weight fractions and crude enzyme preparation from a Trichoderma cellulase complex as a treatment for fibrous feeds. Anim. Feed Sci. Tech. 160:39-48.

Wallace, J. O., L. C. Hollis, C. D. Reinhardt, J. F. Coetzee, D. G. Renter, D. A. Llewellyn, and T. T. Marston. 2007. Failure to eliminate the Anaplasma marginale carrier state in beef cows following multiple treatments with long-acting injectable oxytetracycline. The Bovine Practitioner 41(2)84-87.

Llewellyn, D. A., R. C. Cochran, T. T. Marston, D. M. Grieger, C. G. Farmer, and T. A. Wickersham. 2006. Influence of limited fall protein supplementation on performance and forage utilization by beef cattle grazing low-quality native grass pastures. Anim. Feed Sci. Tech. 127:234-250.

Arroquy, J. I., R. C. Cochran, M. Villarreal, T. A. Wickersham, D. A. Llewellyn, E. C. Titgemeyer,  T. G. Nagaraja, D. E. Johnson, and D. Gnad. 2004. Effect of level of rumen degradable protein and type of supplemental non-fiber carbohydrate on intake and digestion of low-quality grass hay by beef cattle. Anim. Feed Sci. Tech. 115:83-99.

Arroquy, J. I.,  R. C. Cochran, , T. A. Wickersham, D. A. Llewellyn, E. C. Titgemeyer, T. G. Nagaraja, and D. E. Johnson. 2004. Effects of type of supplemental carbohydrate and source of supplemental rumen degradable protein on low quality forage utilization by beef steers. Anim. Feed Sci. Tech. 115:247-263.

Extension Publications

Neibergs, J. S., J. P. Driver, and D. A. Llewellyn.  2015. Valuing canola and camelina biodiesel byproduct meal as a livestock protein supplement.  WSU Extension Fact Sheet FS193E.  Washington State University Extension, Pullman, WA.

Norberg, O. S., and D. A. Llewellyn. 2014. Nitrate poisoning in ruminants. WSU Extension Fact Sheet FS139E. Washington State University Extension. Pullman, WA.

Llewellyn, D. A., and O.S. Norberg. 2014. Prussic acid poisoning in livestock. WSU Extension Fact Sheet FS129E. Washington State University Extension, Pullman, WA.

Bush, M. R., C. Wohleb, S. Rondon, T. Waters, L. DuToit, and D. A. Llewellyn. 2013.  Blister Beetles:  Pest or beneficial predator?  WSU Extension Fact Sheet FS113E.  Washington State University Extension, Pullman, WA.

Llewellyn, D. A., S. M. Smith, and M. Du. 2012. Feeding beef cattle II:  Fetal programming—rethinking cow/calf feeding programs. WSU Extension Fact Sheet EM060E. Washington State University Extension, Pullman, WA.

Llewellyn, D. A. 2012. Feeding beef cattle I:  The realities of low-quality forages.  Extension Manual EM053E.  Washington State University Extension, Pullman, WA.

Harborth, K. W., T. T. Marston, and D. A. Llewellyn. 2006. Comparison of corn and grain sorghum dried distiller grains as protein supplements for growing beef heifers (pp. 3-6). Manhattan, Kansas: Report of Progress 959, Ag. Exp. Sta. Kansas State University.

Hollis, L. C., D. A. Llewellyn, K. L. Teutemacher, T. T. Marston, and M. W. Sanderson. 2006. Performance of calves born to beef cows seropositive but subclinical for bovine Leukosis virus (pp. 31-32). Manhattan, Kansas: Report of Progress 959, Ag. Exp. Sta., Kansas State University.

Harborth, K. W., D. A. Llewellyn, and T. T. Marston. 2005. Influence of early weaning and winter protein supplementation on weight and condition score of spring-calving beef cows grazing native tallgrass prairie (pp. 65-68). Manhattan, Kansas: Report of Progress 943, Ag. Exp. Sta., Kansas State University.

Marston, T. T., L. C. Hollis., D. A. Llewellyn, and G. L. Stokka. 2004. Effect of route of administration of a commercially available Mannheimia (Pasteurella) haemolytica vaccine on titer levels (pp. 91-93). Manhattan, Kansas: Report of Progress 923, Ag. Exp. Sta., Kansas State University.

Hollis, L. C., D. Gnad, T. T. Marston, D. A. Llewellyn, and G. Palmer. 2004. Failure to eliminate the carrier state of anaplasma marginale by using long-acting injectable oxytetracycline (pp. 94-96). Manhattan, Kansas: Report of Progress 923, Ag. Exp. Sta., Kansas State University.

Marston, T. T., D. A. Llewellyn, L. C. Hollis, and J. W. Homm. 2003. Effects of castration age and a growth implant during suckling on weaning and preconditioned weights (pp. 69-71). Manhattan, Kansas: Report of Progress 908, Ag. Exp. Sta., Kansas State University.


  • 2006 – Ph.D. Ruminant Nutrition, Kansas State University
  • 2003 – M.S. Ruminant Nutrition, Kansas State University
  • 1981 – B.S. Animal Science (Production), Oklahoma State University


  • Range Cattle Nutrition and Management
  • Nutrition/Reproduction Interactions
  • Animal Health Management


  • Llewellyn, Donald A., PI, Pratt, Bruce Robert, Co-PI, O’Connor, James Francis, “The Transition to Biofuel Feedstock Production in Kentucky.”  Switchgrass establishment and animal nutrition studies. Sponsored by Kentucky Agricultural Development Board, State, $220,000.00. (September 15, 2009 – May 15, 2011). Funded.
  • Llewellyn, Donald A., PI, Smith, Darrin L., Co-PI, “Biomass Screening Analysis: Rapid Characterization of Feedstock for Biofuels Applications,” Sponsored by EKU Center for Renewable and Alternative Fuel Technologies, Federal, $86,625.00. (January 1, 2010 – December 31, 2010). Funded.

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Office Phone: (509) 735-3551