Louisiana State University School of Veterinary Medicine Equine Health Studies Program 2005 Research Report Dedicated to the Health, Well-Being and Performance of Horses through Veterinary Research, Education and Service Director’s Message Welcome to the 2005 Equine Health Studies (EHSP) Research Report. The purpose of this publication is to document scientific investigations involving equine diseases and injuries. All studies represented in this report were conducted by scientists at the Louisiana State University School of Veterinary Medicine (LSU-SVM) between 2001 and 2003. This report demonstrates the extensive and diverse equine biomedical research conducted at the LSU-SVM. The works contained herein are the collective efforts of our multidisciplinary faculty, advanced studies students, veterinary students, undergraduate students, and technical staff comprising the EHSP. The quality and quantity of these studies is particularly impressive considering the limited intramural funds available during this time. Our ability to acquire extramural support for our program during this period is particularly noteworthy given the highly competitive nature of these funds and the relatively small Dr. Rustin M. Moore, Director number and amount of grants available for equine research. These works Equine Health Studies Program demonstrate the Program’s commitment to promoting the health, well-being and School of Veterinary Medicine performance of horses. Louisiana State University The state-of-the-art facilities and equipment highlighted in this issue represent major advances made in our program since 2003. This progress was facilitated in part by the combination of the receipt of a Governor’s Biotechnology Initiative Grant awarded by the Louisiana Board of Regents, a Board of Regents Enhancement Grant, and recurrent funding through the State Legislature resulting from Louisiana racetrack slot machine revenue. The quality of these facilities provides our faculty, staff, and students with an enriching and stimulating environment in which to conduct leading-edge equine scientific investigations. A 2005 study conducted by the American Horse Council demonstrated that Louisiana’s horse industry ranks fifth nationally in terms of its economic contribution to the Gross Domestic Product. We have a tremendous responsibility to the equine population and horse-owning community that we serve. It is a responsibility that we embrace and continually strive to fulfill through ongoing cutting-edge research and state-of-the-art clinical service. The important findings resulting from the scientific investigations presented in this report would not have been possible without the horses that were utilized for these studies. The availability of horses to be carefully and compassionately used for research is necessary for advancing equine health, and progress toward the future prevention, care and treatment of ill and injured horses. All scientific works conducted at LSU-SVM involving horses are conducted following Federal Guidelines for the Humane Care and Use of Animals. We greatly value the lives of these horses and treat them with the utmost compassion and dignity. We do not use client-owned horses for research; however, retrospective analysis of medical records are sometimes used to assemble information on a series of cases with a specific illness or injury. The information obtained from these records is utilized to determine factors that might prove useful to improve the outcome of horses in the future with similar conditions through enhanced treatments or management strategies. We are extremely proud of the progress we have made and the scholarly findings we have been able to contribute toward promoting and improving equine health. We look to the future with excitement and optimism. We continue to set our sights on establishing the EHSP as one of the premier equine biomedical programs in the world. Respectfully, Rustin M. Moore, DVM, Ph.D., DACVS Director 2005 Research Report Equine Health Studies Program School of Veterinary Medicine Louisiana State University Baton Rouge, Louisiana 70803 Phone: (225) 578-9500 Fax: (225) 578-9605 E-mail: [email protected] Website: www.equine.vetmed.lsu.edu Published by the Equine Health Studies Program, School of Veterinary Medicine, Louisiana State University, Baton Rouge, Louisiana. Dean, School of Veterinary Medicine: Michael G. Groves, DVM, MPH, DACVM, DACVPM, DAVPM Executive Associate Dean: Peter F. Haynes, DVM, MS, DACVS Associate Dean for Research and Advanced Studies: Thomas R. Klei, Ph.D. Director, Equine Health Studies Program: Rustin M. Moore, DVM, Ph.D., DACVS On the Cover: “Wisdom and Anticipation,” an oil painting by Anita Lejeune, a local artist from Lakeland, Louisiana. To view more of the artist’s equine and other works or to inquire about commissioned works, visit her website, www.anitalejeune.com, and help support the LSU Equine Health Studies Program (EHSP). The artist donates 20% of all sales to the EHSP. The Equine Health Studies Program is supported with funds provided by the Louisiana State University School of Veterinary Medicine, the State of Louisiana, and contributions from private donors. Louisiana State University does not discriminate in any of its policies, procedures or practices. The University is an affirmative action/equal opportunity employer. Our Mission: The LSU Equine Health Studies Program will become a premier equine biomedical center in the 21st century through leading-edge research of equine diseases, contemporary instruction of professional veterinary students and veterinarians in advanced studies programs, and enhanced continuing education of the horse-owning public and private equine practitioners with the ultimate goal of providing state-of-the-art diagnostic and therapeutic capabilities for critically ill and injured horses and optimal clinical service to horsemen in Louisiana and the surrounding region. Table of Contents Table of Contents Dean’s Message - Dr. Michael G. Groves ............................................................................................................................... 4 EHSP Faculty ......................................................................................................................................................................... 5 Interdepartmental Equine Health Studies Program ............................................................................................................... 10 EHSP Grants and Contracts ................................................................................................................................................. 11 EHSP Selected Scientific Publications ................................................................................................................................ 13 EHSP Selected Published Scientific Abstracts .................................................................................................................... 17 EHSP Development ............................................................................................................................................................. 21 EHSP Facilities and Equipment ............................................................................................................................................ 22 Anesthesia Cardiopulmonary, behavioral, and analgesic effects of epidural administration ofhydromorphone in standing and anesthetized horses................................................................................................................. 28 Epidural administration of tiletamine/zolazepam in horses........................................................................................ 29 Gastrointestinal Systemic and colonic hemodynamic alterations associated with intravenous administration of ATP-MgCl2 in healthy anesthetized horses..........................................................................................................31 Distribution of endothelin-1 immunohistochemical staining in the intestinal tract of clinically healthy horses and in those with small intestinal and large colon strangulation obstruction............................................ 32 Characterization of endothelin-1 mediated response of equine ileal and cecal smooth muscle..................................34 Plasma concentrations of endothelin-like immunoreactivity in healthy horses and horses with naturally acquired gastrointestinal tract disease.................................................................................................35 Immunology Exercise alters the immune response to equine influenza virus and increases susceptibility to infection................... 37 Effect of aging on T cell responses in horses.............................................................................................................38 Laminitis Effects of an endothelin receptor antagonist on digital hemodynamics and Starling forces in horses administered carbohydrate overload.................................................................................................................. 40 Role of endothelin-1 in naturally-acquired equine laminitis........................................................................................ 41 Quantification of laminar microcirculatory perfusion in normal horses using isotopic-labeled microspheres....................................................................................................................................................