2003 Annual Report 1.What major problem or issue is being resolved and how are you resolving it? The establishment of the Forage-Animal Production Research Unit in Lexington, Kentucky was mandated by Congress in the FY 2002 Appropriations Bill and Signed by the President. After budget increases in FY 2003 the unit has a net to location of $1,967,130. The unit is strategically located near the center of the transition zone of the Eastern and Midwestern United States. As this transition zone is a major contributor to forage animal production in the United States, the unit was established with the mission to improve productivity, profitability, competitiveness and sustainability of forage-based enterprises within the zone. The mission is accomplished through the use of multidisciplinary teams which work to identify, evaluate, and manipulate genetic and physiological factors for the enhancement of food animal and equine health/performance in forage-based enterprises and to improve forage plant persistence/production. Further, the unit, through strategic collaborations, strives to improve environmental sustainability through improved understanding of how manipulation of forage-based enterprises affect the environment. 2.How serious is the problem? Why does it matter? The research team identifies plant metabolites, measures animal responses to metabolite concentrations and identifies plant and animal genes differentially affecting nutrient intake/assimilation and growth and development. Research supports sustainable use of grasslands/pasturelands as a vast renewable resource in the transition zone of the Eastern and Midwestern United States. Further, the research promotes improved profitability and competitiveness for producers throughout the area. Research is in cooperation with the University of Kentucky and other ARS units and Universities. 3.How does it relate to the National Program(s) and National Program Component(s) to which it has been assigned? This project is relevant to NP 205, Rangeland, Pasture and Forages. Relevant components include Plant Resources, Forage Management, and Grazing Management: Livestock Production and the Environment. Relevant unit objectives include: (1) Improve forage plant persistence and performance; (2) Enhance the competitiveness, profitability, and environmental sustainability of forage-based enterprises; and (3) Transfer new technologies and integrated management systems to forage based enterprises. This project is also relevant to NP 101, Food Animal Production. Relevant components include Nutrient Intake and Utilization, Growth and Development, and to a lesser extent portions of Integrated Systems, Genetic Improvement and Genomic Tools. Relevant unit objectives include: (1) Identify factors affecting health and performance of animals produced in forage-based enterprises; (2) Enhance the competitiveness, profitability, and environmental sustainability of forage-based enterprises; and (3) Transfer new technologies and integrated management systems to forage based enterprises. 4.What were the most significant accomplishments this past year? The report serves to document research conducted under a Specific Cooperative Agreement between ARS and the University of Kentucky. Additional details of research can be found in the report for the parent project 6440-21310-001-00D, Enhance Forage-Based Livestock Production Systems. Single Most Significant Accomplishment during FY 2003. Further validation of the Eastern Tent Caterpillar as the apparent carrier of the causative agent for Mare Reproductive Loss Syndrome with significant progress toward identifying the causative agent as potentially being associated with the cuticle of the caterpillar. These findings have allowed for the development of management recommendations that appear to have lessened or alleviated the syndrome in 2003. Other Significant Accomplishment(s), if any. First collaborative project between University of Kentucky Faculty (Dr. Lowell Bush) and FAPRU (Dr. James Strickland and Dr. Carrie Schultz) scientists was successfully initiated concerning horse nutrient and alkaloid metabolism and sample collections completed. Significant Activities that Support Special Target Populations. None. Progress Report. Research Objectives: (1) Determine the etiology of Mare Reproductive Loss Syndrome (MRLS). Status - In Progress. Note: Due to the impact of this syndrome on Kentucky forage-based enterprises and its economy (greater than $400 million loss), most of the first year efforts under this agreement were spent on this objective. Approach - Multidisciplinary teams were established to examine the role of the eastern tent caterpillar as a possible complex with forage, fungi and soil on the etiology of MRLS. (2) Determine the influence of forages on energy regulation in the ruminant. Status - In Planning. A call for proposals is currently under development. Approach - Methodologies will be developed and refined to examine energy partitioning and composition of tissue accretion in ruminants. Data will be integrated using computer-based technology to establish and validate animal performance and production system models. (3) Determine candidate genes and gene products associated with increased efficiency of grazing animal growth and health characteristics. Status - In Planning. A call for proposals is currently under development. Approach - Research will focus on defining the identification, quantification, and elucidation of the biosynthetic pathways of secondary metabolites involved in forage quality. Proteomic analyses will focus on identifying a range of plant products that will form the basis of characterizing forages that enhance animal health and performance. Progress Summary - As the epidemic of reproductive loss in Kentucky mares emerged during the foaling season of 2001 (nearly 3,000 abortions representing approximately one-third of the foals born in Kentucky), many hypotheses were put forward to explain the epidemic which would later be called Mare Reproductive Loss Syndrome (MRLS). Mare Reproductive Loss Syndrome is characterized by losses of early and late pregnancies in 2001 and 2002. The following is a list of hypotheses tested, projects funded and addressing the hypothesis and quick summaries of the findings. Pathogen (bacterial or viral) induced: Projects Supported: Bacteria associated with MRLS: Late-term abortions. J. Donahue, S. Sells, D. Bolin, R. Giles, L. Harrison, C. Hong, K. Poonacha, J. Roberts, M. Sebastian, R. Smith, T. Swerczek, R. Tramontin, M. Vickers, and N. Williams. Findings: No evidence of viral infection recovered. Several bacterial species including streptococci and actinobacilli were recovered from aborted fetuses associated with MRLS. However, data are not conclusive as to this being a/the cause. Phytoestrogen induced: Projects Supported: Phytoestrogens and estrogenic activity in white clover samples from no loss and high loss fields during MRLS 2001 - K. McDowell. Findings: No evidence found to support phytoestrogens as the causative factor of MRLS. Cyanide induced: Projects Supported: Evaluation of the possible role of cyanide in MRLS - L. Dirikolu, M. Sebastian, C. Hughes, J. Crutchfield, A. F. Lehner, K. McDowell, L. Harrison, J. D. Harkins, J. Boyles, A. Troppmann, S. I. Baskin, and T. Tobin. Findings: No evidence found to support cyanide as the causative factor of MRLS Ergot alkaloid/tall fescue induced: Projects Supported: None. Findings: No evidence found to support ergot alkaloids or tall fescue as the causative factor of MRLS Mycotoxin induced: Projects Supported: None. Findings: No evidence found to support mycotoxins as the causative factor of MRLS Eastern Tent Caterpillar (ETC) associated induction: Projects Supported: Induction of MRLS by directed exposure of susceptible mares to eastern tent caterpillar larvae and frass - Experiment 1 - B. A. Webb, W. E. Barney, D. L. Dahlman, C. Collins, N. M. Williams, and K. McDowell. Induction of MRLS by directed exposure of susceptible mares to eastern tent caterpillars and frass - Experiment 2 - B. Webb, W. Barney, D. Dahlman, C. Collins, N. Williams, D. Williams and K. McDowell. Eastern Tent Caterpillar Studies - Frozen caterpillars cause abortion but autoclaved ones do not - K. J. McDowell, N. M. Williams and J. M. Donahue, W. E. Barney and B. A. Webb. Clinical and pathological features of experimentally-induced MRLS late-term abortions with eastern tent caterpillars - M. Sebastian, D. Williams, L. Harrison, J. Donahue, T. Seahorn, N. Slovis, D. Richter, T. Fuller, C. Trail, R. Douglas, and T. Tobin. Preliminary evaluation of a mouse model of MRLS - M. Sebastian, J. D. Harkins, C. Jackson, T. Fuller, P. Van Meter, C. Trail, D. Richter, T. Tobin, S. Howell, and L. Harrison. Age-specific patterns of eastern tent caterpillar dispersal: Implications for reducing MRLS through population management - L.K. Rieske-Kinney. Timing of emergence of eastern tent caterpillars and management with reduced-risk insecticides and treatment strategies - M. Stephens, D. Held, L. Townsend, and D. Potter. Eastern Tent Caterpillars and the Mare Reproductive Loss Syndrome: Clinical, Epidemiological and Mechanistic Implications of a Toxicokinetic/Statistical Analysis - Tobin, T., M. Gantz, J. D. Harkins, M. Sebastian, J. Bosken, C. Hughes, L. Harrison, B. Bernard, and T. D. Fitzgerald. Findings: Evidence supports an association of ETCs with MRLS. However, data are less clear as to the causative agent on/in ETCs that may be inducing MRLS. For example, is the agent a toxicant or a pathogen? Evidence indicates that the causative agent is specific to the ETC but does not appear to be associated with the frass of the insect. Although the agent has not been identified, further evidence as to its properties were discovered. Research has shown that autoclaved ETC's are not pathogenic indicating that the agent is susceptible to heat treatment. Thus, the agent is either a heat labile chemical or biological factor (e.g., bacteria) that is sensitive to autoclaving. Enterobacter and Serratia species may be associated with ETC and MRLS as evidenced by their presence in fetuses from ETC mares. In addition, there is a drastic drop in progesterone and estrogen levels following ETC administration that may provide clues to the mechanism and causative agent(s) associated with MRLS. Histopathological analysis of these fetuses showed hemorrhage and/or congestion of adrenal, liver, kidney, epicardium, thymus, spleen and endometritis. Fetal stress was noted leading up to abortion. As a result of testing aborted fetuses from mares fed ETC's equine herpes virus and letospira have been ruled out. Mice have shown some evidence as being small animal models for ETC induced MRLS. These studies have indicated that the setal portion of the ETC's appears to be associated with MRLS. Exact mechanism and agent still remain to be elucidated. With the association of ETC's with MRLS, it was proposed that managing ETC populations or exposure would limit the extent of MRLS. However, in order to control the populations it is necessary to understand the dispersal parameters associated with the caterpillar. These studies indicated that the caterpillars travel in primarily a northern direction, are responsive to vertically oriented, colored objects and show a preference for black objects over white. Also, the ETC's can travel up to 0.25 miles in about 2.5 hours. Several insecticides have been tested for effectiveness against the ETC's. Of those tested bifenthrin, spinosad, Dipel, and Bidrin were the most effective at various developmental stages of the ETC. Grazing restrictions on two of the more effective bifenthrin and spinosad would limit their utility. Please note that not all of the hypotheses were tested as a result of funding received through the Specific Cooperative Agreement (SCA). As such, only those projects receiving funds were listed with cooperators. Problems Encountered - Facilities for conducting the horse trials were limited. This problem was overcome by utilization of some Specific Cooperative Agreement funds to build a handling and experimental research facility on the Spindletop Farm, owned by the University of Kentucky. The new facilities allowed the additional capacity needed to conduct the team-oriented research used to explore the causes of Mare Reproductive Loss Syndrome. 5.Describe the major accomplishments over the life of the project, including their predicted or actual impact. The major accomplishment over the life of this project thus far is identification of Eastern Tent Caterpillar as the carrier of the causative agent for Mare Reproductive Loss Syndrome. 6.What do you expect to accomplish, year by year, over the next 3 years? Research will continue on identifying the etiologic factors responsible for Mare Reproductive Loss Syndrome (MRLS). Specifically research is ongoing to determine the nature of the causative factor (i.e., pathogen versus toxicant). Along these lines, experiments are currently being designed and implemented to determine if sterilization of eastern tent caterpillars (ETC) and component parts will successfully deactivate the causative agent. Reasoning follows that if sterilized ETC and ETC parts do not cause the syndrome in pregnant mares then the causative agent may not be a pathogen transmitted via ETC. Further, fractionation efforts of the ETC are underway to delineate the portion of the ETC responsible for MRLS. A call for competitive proposals to recruit researchers to address objective two (determining the influence of forages on energy regulation in the ruminant) and objective three (determining candidate genes and gene products associated with increased efficiency of grazing animal growth and health characteristics) is slated to go out by late summer 2003. Funding for successful proposals will commence in fall 2003 with research efforts beginning subsequent to the release of funds to the researchers. It is anticipated that this competitive process will yield a number of quality proposals capable of addressing forage-based enterprise problems as well as the potential to develop into highly competitive extramural programs. 7.What science and/or technologies have been transferred and to whom? When is the science and/or technology likely to become available to the end-user (industry, farmer, other scientists)? What are the constraints, if known, to the adoption and durability of the technology products? None. Unit newly established and staffing underway. 8.List your most important publications in the popular press and presentations to organizations and articles written about your work. (NOTE: This does not replace your peer-reviewed publications listed below). Asbury, A. C. MRLS Workshop. The Horse. 2002. Bain, F. T. and N. M. Williams. 'The Mare Reproductive Loss Syndrome (MRSL): fetal and neonatal problems.' Proceedings of the 2002 American College of Veterinary Internal Medicine Veterinary Medical Forum. Dallas, Texas. 2002. Bolin, D. C., L. R. Harrison, J. M. Donahue, R. C. Giles, C. B. Hong, K. B. Poonacha, J. F. Roberts, M. M. Sebastian, S. F. Sells, R. A. Smith, T. W. Swerczek, R. R. Tramontin, M. L. Vickers, N. M. Williams. "The pericardial correlate of Mare Reproductive Loss Syndrome," In Powell, D. G., A. Troppman, T. Tobin (eds). Proceedings of First Workshop on Mare Reproductive Loss Syndrome, Lexington, KY. 2002:25. Bolin, D. C, L. R. Harrison, J. M. Donahue, R. C. Giles, C. B. Hong, K. B. Poonacha, J. F. Roberts, M. M. Sebastian, S. F. Sells, R. A. Smith, T. W. Swerczek, R. R. Tramontin, M. L. Vickers, N. M. Williams. "Update on the Mare Reproductive Loss Syndrome: Pericarditis" 91st Annual Kentucky Veterinary Medical Association Meeting; Louisville, KY. 2002:5. Brown, S. "Field and clinical observations on late fetal loss (LFL), 2001 and 2002." In Powell, D. G., A. Troppman, T. Tobin (eds). Proceedings of First Workshop on Mare Reproductive Loss Syndrome, Lexington, KY. 2002:14. Camargo, F., L. Dirikolu, M. Sebastian, C. Hughes, J. Crutchfield, J. D. Harkins,J. Boyles, A. Troppmann, K. McDowell, L. Harrison, and T. Tobin. "The toxicokinetics of cyanide and mandelonitrile in the horse and their relevance to the Mare Reproductive Loss Syndrome." Proceedings 14th International Conference Racing Analysts Vets, Orlando, FL, 2002. [KY Ag Exp Sta No. 03-14-071]. Dirikolu, L., M. Sebastian, C. Hughes, J. Crutchfield, A. F. Lehner, K. McDowell, L. Harrison, J. D. Harkins, J. Boyles, A. Troppmann, S. I. Baskin, T. Tobin. "Evaluation of possible role of cyanide in MRLS." In Powell, D. G., A. Troppman, T. Tobin (eds). Proceedings of First Workshop on Mare Reproductive Loss Syndrome, Lexington, KY. 2002:42. Donahue J., S. Sells, D. Bolin, R. Giles, L. Harrison, C. Hong, K. Poonacha, J. Roberts, M. Sebastian, R. Smith, T. Swerczek, R. Tramontin, M. Vickers, and N. Williams. "Bacteria associated with MRLS: late fetal losses." In Powell, D. G., A. Troppman, T. Tobin (eds). Proceedings of First Workshop on Mare Reproductive Loss Syndrome, Lexington, KY. 2002:27. Donahue, J., S. Sells, D. Bolin, R. Giles, L. Harrison, C. Hong, K. Poonacha, J. Roberts, M. Sebastian, R. Smith, T. Swerczek, R. Tramontin, M. Vickers, N. Williams. "Mare Reproductive Loss Syndrome: Bacteriologic Findings in Late-Term Fetal Loss." 91st Annual Kentucky Veterinary Medical Association Meeting, Louisville, KY. 2002:4 Dwyer, R. M., L. Garber, J. Traub-Dargatz, B. Meade, and M. Pavlick, "Dissecting an outbreak of mysterious etiology: Mare Reproductive Loss Syndrome." Proceedings of the 2002 American College of Veterinary Internal Medicine Veterinary Medical Forum, Dallas, Texas. 2002. Dwyer, R. M., L. Garber, J. Traub-Dargatz, B. Meade, M. Pavlick, J. Walker. "An epidemiological investigation of mare reproductive loss syndrome: Breaking ground on a new disease." Society for Veterinary Epidemiology and Preventive Medicine: Veterinary Proceedings. 2002:44-47. Dwyer, R. M. "MRLS epidemiological study." Equine Disease Quarterly. 2001:5-6. Fitzgerald, T. D., P.M. Jeffers, and D. Mantella. "Depletion of host derived cyanide in the gut of the eastern tent caterpillar, Malacosoma americanum." Journal of Chemical Ecology. 2002. 28:257-268. Fitzgerald, T. D., "The tent caterpillars." Ithaca, NY: Comstock Pub. Associates, 1995. xiv, 303 pp. : ill. ; 24 cm. (The Cornell Series in Arthropod Biology.) Green, E. M., "MRLS outbreak response in Florida: the ripple effects." Proceedings of the 2002 American College of Veterinary Internal Medicine Veterinary Medical Forum, Dallas, TX. 2002. Harkins J. D., L. Dirikolu, M. Sebastian, C. Hughes, J. Crutchfield, A. Troppmann, J. Boyles, B. Webb, K. McDowell, W. Long, J. Henning, L. Harrison, T. Fitzgerald, T. Tobin. "Cherry trees, plant cyanogens, caterpillars and Mare Reproductive Loss Syndrome: Toxicological evaluation of a working hypothesis." In Powell, D. G., A. Troppman, T. Tobin (eds), Proceedings of First Workshop on Mare Reproductive Loss Syndrome, Lexington, KY. 2002. pp. 68-74 [KY Ag Exp Sta No. 02-14-167]. Harrison, L. R., "Kentucky equine abortion storm and related conditions." Proceedings of 105th Annual Meeting, United States Animal Health Association. 2001:227-229. Harrison, L. R., D. C. Bolin, J. M. Donahue, R. M. Dwyer, R. C. Giles, J. C. Henning, C. B. Hong, K. J. McDowell, K. Newman, K. B. Poonacha, D. G. Powell, J. F. Roberts, M. M. Sebastian, S. F. Sells, B. J. Smith, R. A. Smith, T. W. Swerczek, T. Tobin, R. R. Tramontin, M. L. Vickers, and N. M. Williams, "Kentucky equine abortion storm and related conditions" [Abstract only]. 44th Annual Meeting American Association of Veterinary Laboratory Diagnosticians, Hershey, PA. 2001: 90. Harrison, L., R. Giles, N. Williams, J. Donahue, C. B. Hong, K. B. Poonacha, D. Bolin, C. Jackson, J. Roberts, M. Sebastian, R. Tramontin, R. Smith, M. Vickers, S. Sells, and B. Smith. "Mare Reproductive Loss Syndrome: overview, veterinary diagnostic laboratory perspective comments regarding recurrence of the syndrome in 2002" [Abstract only]. 91st Annual Kentucky Veterinary Medical Association Meeting, Louisville, KY. 2002:3. Hughes C. G., M. Sebastian, J. Crutchfield, L. Dirikolu, J. D. Harkins, J. Boyles, A. Troppmann, K. McDowell, L. Harrison, and T. Tobin. "A simple, rapid and highly sensitive spectrophotometric method for determination of cyanide in equine biological samples." Toxicology Mechanisms and Methods. 2003. 13:129-138. [KY Ag Exp Sta No. 02-14-85]. Kane, E. and E. Kilby. "Death in the Bluegrass: an epidemic of lost pregnancies, dead foals and sick horses strikes Central Kentucky and beyond, challenging researchers and veterinarians to identify the cause and staunch the unprecedented loss of equine lives." 2001. Equus 287:60-68. Kane, E. and E. Kilby. "The plan pays off: 20/20 hindsight and targeted science guide Kentucky horse breeders through a foaling season free of ugly surprises." 2002. Equus 229:54-61. Latimer, C. "Endopthalmitis: a syndrome associated with Mare Reproductive Loss Syndrome?" Proceedings of First Workshop on Mare Reproductive Loss Syndrome. Lexington, KY. 2002. p. 17-18. Leeson, T. M., D. A. Potter. "Eastern tent caterpillar (Malacosoma americanum) literature having potential relevance to managing Mare Reproductive Loss Syndrome." In Powell, D. G., A. Troppman, T. Tobin (eds). Proceedings of First Workshop on Mare Reproductive Loss Syndrome, Lexington, KY. 2002. p. 120-125. "Mare reproductive loss syndrome." Journal of Equine Veterinary Science. 2001. 21(12):587-588. "Mare reproductive loss syndrome." Journal of Equine Veterinary Science. 2001. 21(5):217-218. "Mare reproductive loss syndrome returns, but losses are fewer - Evidence further suggests that eastern tent caterpillar is culprit." Journal of the American Veterinary Medical Association. 2002. 221(2):179-180. Morehead, J. P., T. L. Blanchard, J. A. Thompson, and S. P. Brinsko, "Evaluation of early fetal losses on four equine farms in central Kentucky: 73 cases (2001)." Journal of the American Veterinary Medical Association. 2002. 220(12):1828-1830. Powell, D. G. Commentary (MRLS). Equine Disease Quarterly. 2001. 10(1):1. Powell, D. G. Commentary (MRLS). Equine Disease Quarterly. 2002. 10(4):1. Powell, D. G. Mare reproductive loss syndrome (MRLS). Equine Disease Quarterly. 2001. 9(4):4-6. Powell, D. G. Mare Reproductive Loss Syndrome. Journal of Equine Veterinary Science. 2002. 22(3):108-110. Powell, D. G. Mare Reproductive Loss Syndrome (MRLS). Bluegrass Equine Reproduction Symposium, Lexington, KY: Hagyard-Davidson-McGee Associates, PLLC. 2002. Notes: pages in symposium are unnumbered. Powell, D. G. An Update on mare reproductive loss syndrome (MRLS) in Kentucky. Conference Proceedings Society for Theriogenology, American College of Theriogenologists, Adam's Mark Hotel, Colorado Springs, Colorado. Nashville, Tenn.: Society for Theriogenology. 2002. p. 147-152. Powell, D. G., A. Troppman, and T. Tobin (eds). Proceedings of the First Workshop on Mare Reproductive Loss Syndrome. Lexington, KY. 2002. Published 2003. Priddy, T. MRLS degree days - what it means. Equine Disease Quarterly. 2002. 10(4):5-6. Reimer, J., Pericarditis outbreak: management and prognosis. Proceedings of the 2002 American College of Veterinary Internal Medicine Veterinary Medical Forum. Dallas, Texas. 2002. Rieske, L. K. Age-specific host utilization in the eastern tent caterpillar, Malacosoma americanum Fabricius (Lepidoptera: Lasiocampidae). Journal of Entomological Science. Submitted February 2003. In press. Rieske, L. K. and L. H. Townsend. Orientation and dispersal patterns of the eastern tent caterpillar, Malacosoma americanum F. (Lepidoptera: Lasiocampidae). Journal of Insect Behavior. Submitted March 2003. Sebastian, M., R. Giles, J. Donahue, S. Sells, R. Tramontin, K. Poonacha, J. Roberts, and L. Harrison. Encephalitis due to Actiniobacillus species in three adult horses. American College of Veterinary Pathologists 53rd Meeting, New Orleans, Louisiana, December 7-11, 2002. Sebastian, M., J. D. Harkins, C. Jackson, T. Fuller, C. Trail, D. Richter, L. Harrison, and T. Tobin. A laboratory animal model of Mare Reproductive Loss Syndrome: preliminary evaluation of a mouse model. In Powell, D. G., A. Troppman. T. Tobin (eds). Proceedings of First Workshop on Mare Reproductive Loss Syndrome, Lexington, KY. 2002. p. 51-53. Sebastian, M., D. Williams, L. Harrison, J. Donahue, T. Seahorn, N. Slovis, D. Richter, T. Fuller, C. Trail, R. Douglas, and T. Tobin: Experimentally Induced Mare Reproductive Loss Syndrome Late Fetal Losses with Eastern Tent Caterpillars. In Powell, D. G., A. Troppman, T. Tobin (eds). Proceedings of First Workshop on Mare Reproductive Loss Syndrome, Lexington, KY. 2002. p. 80-81. Stephens, M., D. W. Held, L. H. Townsend, C. Prater, D. A. Potter. Timing of emergence of eastern tent caterpillars and management with reduced risk insecticides and treatment strategies. In Powell, D. G., A. Troppman, T. Tobin (eds). Proceedings of First Workshop on Mare Reproductive Loss Syndrome, Lexington, KY. 2002. p. 92-95. Swerczek, T. W. Saprotrophic fungi and bacteria and commensal bacteria that infect frost-damaged pastures may be contributing to microbial overgrowth and lesions associated with the Mare Reproductive Loss Syndrome. Journal of Equine Veterinary Science. 2002. 22(6):234-236. Taylor, J. R. Theory of ammonia toxicity as the mechanism of abortion in the Mare Reproductive Loss Syndrome. Journal of Equine Veterinary Science. 2002. 22(6):237-239. Thalheimer, R. and R. G. Lawrence. The economic loss to the Kentucky breeding industry from Mare Reproductive Loss Syndrome (MRLS) of 2001. Produced for the Office of the Governor, Commonwealth of Kentucky by Dr. Richard Thalheimer (Principal Investigator) and Dr. Robert G. Lawrence (Co-Principal Investigator); Department of Equine Business, College of Business and Public Administration, University of Louisville, Louisville, KY. 2001:48. Tobin, T., M. Gantz, J. D. Harkins, M. Sebastian, J. Bosken, C. Hughes, L. Harrison, B. Bernard, T. D. Fitzgerald. Eastern Tent Caterpillars and the Mare Reproductive Loss Syndrome: Clinical, Epidemiological and Mechanistic Implications of a Toxicokinetic/Statistical Analysis. Article No. 331. Equine Pharmocology and Experimental Therapeutics Program, Maxwell H. Gluck Equine Research Center and the Department of Veterinary Science, University of Kentucky. 2003. Tobin, T. The Mare Reproductive Loss Syndrome: an ongoing toxicological/other investigation. Submitted for publication to Bain-Fallon Lectures, Gold Coast, Australia. 2002. Tobin T., K. McDowell, C. G. Hughes, A. F. Lehner, J. Crutchfield, J. D. Harkins, L. Dirikolu, M. Sebastian, L. Harrison, N. Williams, R. Smith, B. Webb, K. Newman, R. Allman, R. Dwyer, and D. Powell. The Kentucky 2001 Mare Reproductive Loss Syndrome: overview and preliminary toxicological approaches. [Abstract only] Proceedings of 14th International Conference Racing Analysts Vets, Orlando, FL. 2002. Webb B. A., W. E. Barney, D. L. Dahlman, S. N. DeBorde, C. Weer, N. M. Williams, J. M. Donahue, and K. J. McDowell. Experimental Evidence that Eastern Tent Caterpillars Cause Mare Reproductive Loss Syndrome. Biological Bulletin. Submitted 2003. Williams, N. M. Mare reproductive loss syndrome: pathologic findings. Equine Disease Quarterly. 2002. 10(4):4-5. Williams, N. M., D. C. Bolin, J. M. Donahue, R. C. Giles, L. R. Harrison, C. B. Hong, K. B. Poonacha, J. F. Roberts, M. M. Sebastian, T. W. Swerczek, and R. R. Tramontin. Gross and histopathological correlates of MRLS. Proceedings of First Workshop on Mare Reproductive Loss Syndrome, Lexington, KY. 2002. p. 24-25. Williams, N. M., D. C. Bolin, J. M. Donahue, R. C. Giles, L. R. Harrison, C.B. Hong, K. B. Poonacha, J. F. Roberts, M. M. Sebastian, T. W. Swerczek, R. R. Tramontin. "Mare Reproductive Loss Syndrome: Pathologic Findings." 91st Annual Meeting Kentucky Veterinary Medical Association and 29th Mid-America Veterinary Conference, Louisville, Kentucky. October 11, 2002. p. 6.