Faculty
Deon van der Merwe
BVSc 1994, University of Pretoria
BSc (Hons) (Wildlife Management) 1998, University of Pretoria
MSc (Vet Sc) 2000, University of Pretoria
PhD (Comparative Biomedical Sciences) 2005, North Carolina State University
Assistant Professor of Toxicology
Phone: 785–532 4333
Fax: 785–532 4481
Email: dmerwe@vet.ksu.edu
Research
As a veterinarian and a comparative biomedical scientist, my research interests are varied and include aspects of environmental toxicology and ecotoxicology, the use of mathematical and spatial models in toxicology, and veterinary botany.
We live in a chemical world. Sometimes the exposure to chemicals can be harmful depending on the type of chemical and the rates of exposure. My work in environmental toxicology and ecotoxicology is focused on the movement of chemicals in the environment that determines the exposure to various organisms.
My work in mathematical modeling involves studies of the absorption of chemicals into the body following skin exposure. This work includes efforts to better understand the mechanisms of absorption, as well as in vitro experiments aimed at determining the rates of absorption of particular chemicals and formulations.
Plants contain biologically active compounds that can have both toxic and potentially useful effects. I am interested in the interactions between people, plants and animals where it involves plant toxicity and the use of plants as medicines. Poisonous plants often cause serious livestock losses. These losses are typically associated with specific environmental conditions related to climate, soil, the life stage of the plants and management practices. I am interested in characterizing the environmental conditions that are correlated with animal losses due to plant poisoning.
Teaching
I teach the following courses
- Veterinary Toxicology (DMP 801)
- Advanced Toxicology (DMP 803)
- Ecotoxicology (DMP 804)
- Environmental Toxicology (DMP 806)
- Problems in Toxicology (DMP 809)
Service
I manage the Toxicology Section of the KSU Veterinary Diagnostic Laboratory. The Toxicology Section provides diagnostic services to veterinary colleagues and the general public.
Publications
Peer-reviewed publications
Hanzlicek A, Van der Merwe D 2010. Dibucaine toxicosis in a dog. Journal of Medical Toxicology 6:44-49.
Schumm P, Scoglio CM, Van der Merwe D 2009 A network model of successive partitioning-limited solute diffusion through the stratum corneum. Journal of Theoretical Biology 262:471-477.
Al-Bataneih MM, Van der Merwe D, Schultz BD, Gehring R 2009 Cultured mammary epithelial monolayers (BME-UV) express functional organic anion and cation transporters. Journal of Veterinary Pharmacology and Therapeutics 32(5):422-428
Van der Merwe D, Tawde S, Pickrell JA, Erickson LE 2009 Nanocrystalline titanium dioxide and magnesium oxide in vitro dermal absorption in human skin. Cutaneous and Ocular Toxicology 28(2):78-82
Van der Merwe D, Tawde S 2008 Antacids in the initial management of metallic zinc ingestion in dogs. Journal of Veterinary Pharmacology and Therapeutics 32:203-206
Oliver C M, Skinner J D, Van der Merwe D 2007 Territorial behaviour in southern impala rams (Aepyceros melampus Lichtenstein). African Journal of Ecology 45(2):142-148
Spickett A M, Van Der Merwe D, Matthee O 2007 The effect of orally administered Aloe marlothii leaves on Boophilus decoloratus tick burdens on cattle. Experimental and Applied Acarology 41(1-2):139-46
McGaw LJ, Van der Merwe D, Eloff JN 2007 In vitro anthelmintic, antibacterial and cytotoxic effects of extracts from plants used in South African ethnoveterinary medicine.Veterinary Journal 173(2):366-72.
Van der Merwe D, Du Plessis L 2006 Microscopic morphology of Dichapetalum cymosum (Hook.) Engl. as an aid in the identification of leaf fragments in the digestive tract of poisoned animals. Journal of the South African Veterinary Association 77(4):197-201
Van der Merwe D, Riviere J E 2006 Cluster analysis of the dermal permeability and stratum corneum/solvent partitioning of ten chemicals in twenty-four chemical mixtures in porcine skin. Skin Pharmacology and Physiology 19(4):198-206
Luseba D, Van der Merwe D 2006 Ethnoveterinary medicine practices among Tsonga speaking people of South Africa. Onderstepoort Journal of Veterinary Research 73(2):115-122
Van der Merwe D, Brooks JD, Gehring R, Baynes RE, Monteiro-Riviere NA, Riviere JE 2006 A physiologically based pharmacokinetic model of organophosphate dermal absorption. Toxicological Sciences 89(1):188-204
Van der Merwe D, Riviere J E 2005 Effect of vehicles and sodium lauryl sulphate on xenobiotic permeability and stratum corneum partitioning in porcine skin. Toxicology 206:325-335
Van der Merwe D, Riviere J E 2005 Comparative studies on the effects of water, ethanol and water/ethanol mixtures on chemical partitioning into porcine stratum corneum and silastic membrane. Toxicology In Vitro 19(1):69-77
Gehring R, Van der Merwe D, Pierce AN, Baynes RE, Craigmill AL, Riviere JE 2005 Multivariate meta-analysis of pharmacokinetic studies of ampicillin trihydrate in cattle. American Journal of Veterinary Research 66(1):108-112
Botha C J, Shakespeare A S, Gehring R, Van der Merwe D 2001 Evaluation of a commercially available molybdate formulation and zinc oxide boluses in preventing hepatic copper accumulation and thus enzootic icterus in sheep. Journal of the South African Veterinary Association 72(4): 183-188
Van der Merwe D, Swan G E, Botha C J 2001 Use of ethnoveterinary medicinal plants in cattle by Setswana-speaking people in the Madikwe area of the North West province of South Africa. Journal of the South African Veterinary Association 72(4): 189-196
Scientific meeting abstracts
Petersen D, Burr D, Pohlman L, Galgut B, Van der Merwe D, Ganta C, Nietfeld J C 2009 Hepatic copper accumulation and liver cirrhosis in a dog. Paper presented at the 2009 ACVP/ASVCP Annual Meeting, Monterey, December 5-9, 2009.
Nietfeld J C, Van der Merwe D, Fisher D, Loughney K 2009 Copper Deficiency in Kansas Bison Paper presented at the 52nd Annual AAVLD/USAHA Meeting, San Diego, October 7-14, 2009.
Wisely S M, Van der Merwe D, Montelone B, Harkin K, Freeman L 2009 A call for collaborators: Developing a One Health Initiative across the LTER Network. Poster presented at the All Scientists Meeting, National Science Foundation – Long Term Ecological Research Program, Estes Park, September 13-17 2009
Jones M, Van der Merwe D 2009 Copper Toxicity in Small Ruminants. Proceedings of the Montana Veterinary Medical Association Summer Meeting, Billings, June 21-22, 2009.
Al-Bataineh M M, Van der Merwe D, Schultz B D, Coetzee J, Apley M, Gehring R 2009. Molecular and Functional Identification of Organic Anion Transporter Isoforms and Efflux Pump (P-gp) in Cultured Bovine Mammary Epithelial Cells (BME-UV). Poster presented at the AAVPT 16th Biennial Symposium, Rockville, June 14-17, 2009.
Nietfeld J C, Fisher D, Loughney K, Van dere Merwe D 2009 Copper deficiency in a herd of Kansas bison. Paper presented at the K-State VMCE 71st Annual Conference for Veterinarians, June 7-10, 2009
Pickrell J A, Dhakal K, Erickson L E, Klabunde J K, Maghirang R G, Dhakal M, Van der Merwe D, Oehme F W 2008 Potential inhalation toxicity of nanomaterials. Paper presented at the American Institute of Chemical Engineers Annual Meeting, Philadelphia, November 16-20, 2008.
Van der Merwe D, Tawde S, Price KP 2008 Environmental effects on forage nitrate accumulation, and its association with climate change in the North American Great Plains. Paper presented at the 51st Annual Conference of the International Association for Vegetation Science, Stellenbosch, South Africa, September 7-12, 2008
Kershner T, Gehring R, Van der Merwe D, Beech C 2008 A spatial database of ethnoveterinary medicinal plant use in and around the Greater Limpopo Transfrontier Conservation Area. Poster presentated at the Society of Economic Botany’s 2008 Annual Meeting, Durham, USA, June 1-5, 2008
Tawde S, Van der Merwe D 2008 Nitrate toxicity risk assessment: from field sampling to remote sensing and beyond. Poster presentated at the Society of Toxicology’s 47th Annual Meeting, Seattle, USA, March 16-20, 2008
Van der Merwe D 2007 Correlations between normalized difference vegetation index data patterns and hazardous nitrate accumulation in forage plants. Poster presentated at the AAVLD 50th Annual Conference, Reno, USA, October 18-23, 2007
Van der Merwe D, Wellman L, Gehring R 2007 Effective tortuosity applied to inter-species scaling of parathion dermal absorption in bovine and rat skin. Poster presentated at the Society of Toxicology’s 46th Annual Meeting, Charlotte, USA, March 25-29, 2007
Van der Merwe D, Brooks JD, Gehring R, Baynes RE, Monteiro-Riviere NA, Riviere JE 2006 A physiologically based pharmacokinetic model of parathion dermal absorption. Poster presentated at the Society of Toxicology’s 45th Annual Meeting, San Diego, USA, March 5-9, 2006
Van der Merwe D, Gehring R, Baynes RE, Monteiro-Riviere NA, Riviere JE 2005 A physiologically based pharmacokinetic model of fenthion absorption through porcine skin in a flow-through cell. Presented at: 14th Bienniel Symposium of the American Academy of Veterinary Pharmacology and Therapeutics, Washington DC, USA, May 16-18, 2005
Gehring R, Van der Merwe D, Baynes RE, Riviere JE 2005 A mechanistic mathematical model to predict milk concentrations of parenterally administered drugs. Presented at: 14th Bienniel Symposium of the American Academy of Veterinary Pharmacology and Therapeutics, Washington DC, USA, May 16-18, 2005
Van der Merwe D, Riviere JE 2004 A comparative investigation of the effects of water, ethanol and water/ethanol mixtures on chemical partitioning into porcine stratum corneum and permeability in porcine skin. Poster presentated at the Society of Toxicology’s 43rd Annual Meeting, Baltimore, USA, March 21-25, 2004
Van der Merwe D 2002 Ethnoveterinary medicine in southern Africa: key concepts and implications. Paper presented at the Indigenous Plant Use Forum, George, South Africa, July 9-12, 2002
Katsoulis LC, Gehring R, Van der Merwe D 2002 The effect of Sclerocarya birrea aqueous bark extracts on rat intestinal contractility.Poster presented at the Indigenous Plant Use Forum, George, South Africa, July 9-12, 2002
Van der Merwe D 1999 Ethnoveterinary plant use in cattle by Setswana-speaking people in the North West Province of South Africa. Poster presented at the Second International Conference on Pharmaceutical and Pharmacological Sciences (South Africa), Cape Town, South Africa, October 3-6, 1999
Book chapters
Van der Merwe D 2009 Chapter 145: Poisons of plant origin. In: General and Applied Toxcology (3rd ed), Bryan Ballantyne, Timothy C. Marrs, Tore Syversen (eds.), Wiley, Hoboken, NJ, Volume 6, pp. 3449-3466.
Gehring R, Van der Merwe D 2008 Drug interactions. In: Haskell SSR (ed.) Five Minute Veterinary Consult, Rruminant. Wiley-Blackwell Publishing, Aimes, Iowa, 310-311
Gehring R, Van der Merwe D 2008 Drug hypersensitivity. In: Haskell SSR (ed.) Five Minute Veterinary Consult, Rruminant, Supplementary Material. Wiley-Blackwell Publishing, Aimes, Iowa, 176
Gehring R, Van der Merwe D 2008 Prudent use of antimicrobials. In: Haskell SSR (ed.) Five Minute Veterinary Consult, Rruminant, Supplementary Material. Wiley-Blackwell Publishing, Aimes, Iowa, 327-328
Van der Merwe D, Buur J L, Riviere J E 2007 Physiologically Based Pharmacokinetic Modeling. In: Gupta R C, (ed.) Veterinary Toxicology: Basic & Clinical Principles. Elsevier/Academic Press, New York, 42-50
Other publications
Van der Merwe D, Carpenter JW, Nietfeld JC 2010 Adverse health effects in Canada geese (Branta canadensis) associated with waste from zinc and lead mines in the Tri-State Mining District. Report to the United States Fish and Wildlife Service
DeBey B, Van der Merwe D 2009 Blue-green algae toxicosis in dogs in Kansas. Kansas Veterinary Quarterly for the Practicing Veterinarian, 12(2):5
Jones M, Van der Merwe D 2008 Copper toxicity is on the rise in Kansas and Nebraska. Kansas Veterinary Quarterly for the Practicing Veterinarian, Fall 2008, 11(4):2-3
Pickrell JA, Nietfeld J, Kuroki K, Blevins L, Van der Merwe D, Oehme FW 2007 Case study: Poor quality hay leads to nitrate intoxication. Kansas Veterinary Quarterly for the Practicing Veterinarian, Winter 2007, 11(1):6-7
K-State Media Relations Podcast: Toxic hazards for pets (http://www.ksu.edu/media/audio/podcastindex.html)
K-State Media Relations News Release: K-state animal poison control hotline available 8 a.m. to 5 p.m. regular business days. Prepared by Shelby Haag December 11, 2007 (http://www.ksu.edu/media/newsreleases/dec07/poisonhotline121107.html)
Book review: A S Thoresen 2001 Alternative and complementary medicine. Review by D van der Merwe and R Gehring 2002 Journal of the South African Veterinary Association 73(1): 43
Book review: Martin M, Mathias E, McCorkle C M 2001 Ethnoveterinary Medicine – An annotated bibliography of community animal health care. Review by D van der Merwe 2001 Journal of the South African Veterinary Association 72(3): 172