Parasite drug resistance is now recognized globally as one of the greatest health threats to grazing livestock. Also, in recent years there has been a dramatic increase in the use of mass drug administration to reduce the morbidity associated with helminth infections of humans, raising the likelihood that anthelmintic resistance may become a public health concern in the near future.

To address this problem, my laboratory pursues research projects with four different areas of emphasis:

1. Measuring the prevalence of drug resistance
2. Studying the molecular basis of anthelmintic resistance
3. Developing in vitro and molecular diagnostic assays to detect emerging resistance in nematode populations
4. Studying and developing novel and sustainable approaches to parasite control that rely less heavily on chemical anthelmintics

Most of our research focuses on nematode parasites of livestock; however, we also work on human and animal filarial nematode parasites. Recently we have developed projects investigating the possibility that resistance to the macrocyclic lactone anthelmintics has developed in the canine heartworm, Dirofilaria immiits.

We are also involved in studies investigating novel and sustainable approaches to nematode parasite control in sheep and goats. This work is being conducted under the auspices of the Southern Consortium for Small Ruminant Parasite Control (www.scsrpc.org) in collaboration with a multi-disciplinary team of veterinarians, scientists and small ruminant extension specialists from institutions throughout the southern United States as well as the University of Pretoria and the Onderstepoort Veterinary Institute in South Africa.

One of the most promising approaches for the control of Haemonchus contortus is the FAMACHA© method for identifying anemic animals in need of treatment. Using this method, a targeted selective treatment program can be instituted. This approach allows farmers to identify those animals in need of treatment, but also those that do not need treatment. Thus parasites are controlled, while at the same time refugia levels are managed, thereby reducing the selection pressure for drug resistance.

Since its introduction in the U.S. in 2003, FAMACHA© has been warmly embraced by farmers, and recent surveys of farmers trained in FAMACHA© suggest it is making an important impact. The Kaplan lab is the distributor for the FAMACHA© anemia color charts in the U.S. (under the auspices of the Southern Consortium for Small Ruminant Parasite Control), with Dr. Kaplan serving as director and Bob Storey serving as manager of the U.S. FAMACHA© program. See www.scsrpc.org or contact famacha@uga.edu for more information. Finally, our laboratory also maintains constant surveillance for the detection of new occurrences of anthelmintic resistance (and multiple-drug resistance) in parasites that have not been recognized previously to be drug-resistant (and/or multiple-drug resistant) in the U.S.

RECENT PUBLICATIONS

Search PubMed for "Kaplan, Ray"

Shulin, X., L. Canhui,  G. Tzertzinis, E. Ghedin, C.C. Evans, R.M. Kaplan, T.T.  Unnasch, 2011.  In vivo transfection of developmentally competent Brugia malayi infective larvae, International Journal for Parasitology, 41:355-362.

Kaplan, R. M. and M. K. Nielsen. 2010.   An evidence-based approach to equine parasite control: It ain’t the 60s anymore, Equine Veterinary Education, 22 (6) 306-316.

Juraseka, M.E., Bishop-Stewart, J.K., Storey, B.G., Kaplan, R.M., Kent, M.L., 2010.  Modification and further evaluation of a fluorescein-labeled peanut agglutinin test for identification of Haemonchus contortus eggs, Veterinary Parasitology, 169:209-213.

Ionita, M., Howe, D.K., Lyons, E.T., Tolliver, S.C., Kaplan, R.M., Mitrea, I.L., Yeargan, M. 2010. Use of a Reverse Line Blot assay to survey small strongyle (Strongylida: Cyathostominae) populations in horses before and after treatment with ivermectin, Veterinary Parasitology, 168:332-337.

Nielsen, M.K., Vidyashankar, A.N., Andersen, U.V., DeLisi, K., Pilegaard, K., Kaplan, R.M. 2010. Effects of fecal collection and storage factors on strongylid egg counts in horses, Veterinary Parasitology, 167:55-61.

Lake, S., Matthews, J., Kaplan, R., Hodgkinson, J., 2009. Determination of genomic DNA sequences for beta-tubulin isotype 1 from multiple species of cyathostomin and detection of resistance alleles in third-stage larvae from horses with naturally acquired infections. Parasites & Vectors, 2 (Suppl 2), S6.

Burke, J.M., A. Wells, P. Casey, R.M. Kaplan. 2009. Herbal dewormer fails to control gastrointestinal nematodes in goats, Veterinary Parasitology 160:168-170.

Schwenkenbecher, J.M., R.M. Kaplan.  2009.  Real-time PCR assays for monitoring benzimidazole resistance associated mutations in Ancylostoma caninum, Experimental Parasitology, 122(1):6-10.

Fontenot, D.K., Kinney- Moscona, A., R.M. Kaplan, Miller, J.E., 2008. “Effects of copper oxide wire particle bolus therapy on trichostrongyle fecal egg counts in exotic artiodactylids,” Journal of Zoo and Wildlife Diseases, 39(4):642-645.

Howell, S.B., J.M. Burke, J.E. Miller, T.H. Terrill, E. Valencia , M.J. Williams, L.H. Williamson, A.M. Zajac, R.M. Kaplan. 2008. Anthelmintic resistance on sheep and goat farms in the southeastern United States, JAVMA, 233(12):1913-1919.

Hodgkinson, J.E., H. J. Clark, R. M. Kaplan, S.L.Lake, J.B. Matthews.  2008.  The role of polymorphisms at beta tubulin isotype 1 codons 167 and 200 in benzimidazole resistance in cyathostomins, International Journal for Parasitology, 38:1149-1160.

Nielsen, M.K.,D.S. Peterson, J. Monrad, S.M. Thamsborg, SN. Olsen, R.M. Kaplan. 2008. Detection and semi-quantification of Strongylus vulgaris DNA in equine faeces by real-time PCR. International Journal for Parasitology, 38:443-453.

Vidyashankar, A.N., R.M. Kaplan, S. Chan.  2007. Statistical approach to measure efficacy of anthelmintic treatment on horse farms, Parasitology, 134:2027-2039.

Schwenkenbecher, J.M., M. Albonico, B. Quentin, R.M. Kaplan. 2007.  Characterization of beta-tubulin genes in hookworms and investigation of resistance-associated mutations using real-time PCR.  Molecular and Biochemical Parasitology, 156:167-174.

Nielsen, M.K., R.M. Kaplan, S.M.Thamsborg, J. Monrad, and S.N. Olsen.  2007. Climatic influences on development and survival of free-living stages of equine strongyles: Implications for worm control strategies and managing anthelmintic resistance. The Veterinary Journal, 174:23-32.

Burke, J.M., R.M. Kaplan, J.E. Miller, T.H. Terrill, W.R. Getz, S. Mobini, E. Valencia, M.J. Williams, L.H. Williamson and A.F. Vatta.  2007. Accuracy of the FAMACHA system for on-farm use by sheep and goat producers in the southeastern United States. Veterinary Parasitology 147:89-95.

Kaplan, R.M., A. N. Vidyashankar, S.B. Howell, J.M. Neiss, L.H. Williamson, and T.H. Terrill. 2007.  A novel approach for combining the use of in vitro and in vivo data to measure and detect emerging moxidectin resistance in gastrointestinal nematodes of goats. International Journal for Parasitology, 37:795-804.

Schwenkenbecher, J.M. and Kaplan, R.M. 2007. Development and characterization of microsatellite markers for the canine hookworm, Ancylostoma caninum. Parasitology Research, 100:1015-1021.

Kaplan, R.M., A. N. Vidyashankar, S.B. Howell, J.M. Neiss, L.H. Williamson, and T.H. Terrill. 2007. A novel approach for combining the use of in vitro and in vivo data to measure and detect emerging moxidectin resistance in gastrointestinal nematodes of goats. International Journal for Parasitology, 37:795-804.

Burke, J.M., R.M. Kaplan, J.E. Miller, T.H. Terrill, W.R. Getz, S. Mobini, E. Valencia, M.J. Williams, L.H. Williamson and A.F. Vatta. 2007. Accuracy of the FAMACHA system for on-farm use by sheep and goat producers in the southeastern United States. Veterinary Parasitology 147:89-95.

Nielsen, M.K., R.M. Kaplan, S.M.Thamsborg, J. Monrad, and S.N. Olsen. 2007. Climatic influences on development and survival of free-living stages of equine strongyles: Implications for worm control strategies and managing anthelmintic resistance. The Veterinary Journal, 174:23-32.