Skip to main content


Ronald Baynes, B.Sc. DVM, M.S., Ph.D

Professor of Pharmacology

Office: 919.513.6261

Dr. Baynes obtained his B.Sc. (Biology) from the University of the West Indies, veterinary degree from Tuskegee University, MS in pharmacology from the University of Georgia, and Ph.D. in pharmacology from North Carolina State University. He is currently a Professor of Pharmacology at NCSU College of Veterinary Medicine and prior to his current appointment, he was a Toxicologist at Syracuse Research Corporation in Atlanta, GA.
Dr. Baynes’ primary responsibilities at NCSU College of Veterinary Medicine for the last 21 years include teaching and research in two areas of quantitative pharmacology and toxicology. (1) Formulation and mixture effects on drug and chemical disposition of topical formulations leading to the development of Quantitative Structure Activity Relationship (QSAR) models to inform risk assessment of skin exposures to chemical mixtures. (2) Contaminant and veterinary drug residue pharmacology and development of novel pharmacokinetics modeling approaches to inform risk management of veterinary drug residues via the national Food Animal Residue Avoidance Databank (FARAD) program.
Dr. Baynes’ research at NCSU has been supported by several NIH, USDA, US DOD, and industrial grants. He has generated more than 130 peer-reviewed publications and book chapters pertaining to his teaching, extension, and research activities. In addition to training of veterinary graduate students in his laboratory, he is actively involved in preparing undergraduate and DVM students for careers in veterinary research through several honors and summer programs.
American Chemical Society
Society of Toxicology
American Academy of Veterinary Pharmacology and Therapeutics
Sigma Xi
DVM, Tuskegee University
PhD, Pharmacology, North Carolina State University
MS, Pharmacology, University of Georgia
BSc, Biology, University of the West Indies
Computational Biology and Bioinformatics, Pharmacology
Dermal Absorption Assessment: The focus of my research is to determine physiochemical and chemical-biological interactions in epidermal corneocytes and intercellular lipids in the epidermis that can influence dermal absorption of complex mixtures.

Dermal Absorption: Current research activities are focused on assessing the dermal disposition of cutting fluid and jet fuel additives and pesticides. This research is providing some understanding of the physicochemical factors influencing dermal absorption of these pesticides and formulation additives that cause occupational irritant dermatitis. Other work is focused on understanding transdermal delivery of avermectins across skin various food animal species. HPLC and GC analytical methods are continually being developed.

Residue Pharmacology and Risk Assessment of Veterinary Drugs: Current Research and Extension Activities are focused on providing expert consultation to veterinarians and livestock farmers about drug/chemical residues in livestock, development of algorithms for estimating safe withdrawal times, development of provisional acceptable residues as temporary safe levels in animal-derived food, and development of residue monitoring and residue avoidance programs internationally (gFARAD). The laboratory has been active in HPLC analytical method development for antibiotic residues in milk.
Comparative Pharmacokinetics
  • (2018) Effect of three phytoceutical products on elimination of bacteria in experimentally-induced Streptococcus uberis clinical mastitis.Mullen, K. A. E., Lyman, R.L., Washburn, S.P., Baynes, RE., and Anderson, K.L. | J. Dairy Sci. (in press).
  • (2018) Genetic parameter estimates for metabolizing two common pharmaceuticals in swine.Howard, JT, Ashwell, MS., Baynes, RE, Brooks, JD., Yeatts, JL., Maltecca, C. | Front. Genet. (in press)
  • (2018) Impact of synthetic canine cerumen on the in vitro auricular skin penetration of florfenicol, terbinafine and betamethasone acetate in dogs.Ehling, S., Baynes, RE., Baumer, W. | Amer. J. Vet. Res. (in press).
  • (2017) Pharmacokinetic analysis of thymol, carvacrol and diallyl disulfide (garlic extract) after intramammary and topical applications in healthy organic dairy cattle.Mason, SE., Mullen, KE., Anderson, KL., Washburn, SP., Yeatts, JE., and Baynes, RE. | Food Addit. Contam. doi: 10.1080/19440049.2017.1285056.
  • (2017) Gene co-expression network analysis identifies porcine genes associated with variation in metabolizing fenbendazole and flunixin meglumine in the liver.Howard, JT, Ashwell, MS., Baynes, RE, Brooks, JD, Yeatts, JL, Maltecca, C. | Scientific Reports   May 2;7(1):1357. doi: 10.1038/s41598-017-01526-5.
  • (2017) Potential of phytoceutical products to cause positive results on antibiotic residue detection tests.Mullen, KAE., Beasley, E., Washburn, SP., Baynes, RE., Rizzo, JQ., Anderson, KL. | Vet. Record. 2017;0:e000214. doi:10.1136/vetreco-2016-000214.
  • (2017) Evaluation of 1 2-aminoimidazole variant as adjuvant treatment for dermal bacterial infections.Draughn, GL., Allen, CL., Routh, PA., Stone, MR., Kirker, KR., Schuchman RM., Linder, KE., Baynes RE., Garth, J., Melander, CM., Pollard, A., and Cavanagh, J. | Drug Design Develop. Ther. 11:153-162.
  • (2017) Pharmacokinetics of 14C-Ortho-Phenylphenol Following Intravenous Administration in Pigs.*Nixon, E., Brooks, J., Routh, P., and Baynes, RE. | J. Appl. Toxicol. 37(4):508-512.
  • (2017) Pharmacokinetics and distribution in interstitial and pulmonary epithelial lining fluid of 2 danofloxacin in ruminant and preruminant calves.*Mzyk, DA., Baynes, R.E., Martinez, M., Smith, G.W. | J. Vet. Pharmacol. Therap. 40(2):179-191.
  • (2016) Development of HS-SPME-GC/MS/MS method for the quantification of thymol and carvacrol in bovine matrices and to determine residue depletion in milk and tissues.*Armorini, S., Yeatts, J., Mullen, K., Mason, S., Anderson, KL., Washburn, S., Baynes, RE. | J. Agric Food Chem. 64: 7856-7865.
  • (2016) Pharmacokinetics and tissue elimination of flunixin in veal calves.*Kissel, L.W., Brinson PD, Gehring R, Tell LA, Wetzlich SE, Baynes RE, Riviere JE, Smith GW. Am. | J. Vet. Res 77(6):634-640.
  • (2015) Tissue residues after label and extra-label administration of flunixin meglumine to saline or lipopolysaccharide-exposed dairy cows.Smith, D; Shelver, W.; Baynes, R, Tell, L; Gehring, R, Li, M, Dutko, T, Schroeder, JW; Herges, G, Riviere, J. | J. Agric Food Chem. 63(19): 4893-4901.
  • (2015) Differential gene expression across breed and sex in commercial pigs administered fenbendazole and flunixin meglumine.*Howard, J.T., O’Nan, A.T., Maltecca, C., Baynes, R.E., Ashwell, M.S. | PLoS ONE 10(9): e0137830. doi:10.1371/journal. pone.0137830.
  • (2015) Tissue concentrations of sulfamethazine and tetracycline hydrochloride of swine (Sus scrofa domestica) as it relates to withdrawal methods for international export.Mason, S., Wu, H., Yeatts, J., and Baynes RE. | Reg. Pharmacol. Toxicol. 71(3): 590-596.
  • (2015) Skin absorption of six performance amines used in metalworking fluids.*Roux LN, Brooks JD, Yeatts JL, Baynes RE. | J Appl Toxicol. 35(5):520-528.
  • (2015). Pharmacokinetics of intramammary hetacillin in dairy cattle milked 3 times per day.*Lindquist, DA, Baynes RE, Smith GW. | J. Dairy. Sci. 98(3): 1856-1861.
  • (2015)  Comparison of flunixin pharmacokinetics and milk elimination in healthy cows and cows with mastitis.Kissell*, L., Leavens, T., Baynes, RE., Riviere, JE., Smith, G | J. Amer. Vet. Med Assoc. 246(1):118-125