COMPARISON OF ISOFLURANE AND SEVOFLURANE ANESTHESIA FOLLOWING PREMEDICATION WITH BUTORPHANOL IN THE GREEN IGUANA (Iguana iguana) Sonia M. Hernandez-Divers, D VM, Dipl ACZM,' * Juergen Schumacher, Dr.med. vet., Dipl ACZM,' Matt R. Read, DVM, MVSc, Dip1 ACVA,' Scott Stahl, D VM, AB VP (A~ian),~and Stephen Hernandez-Divers, B VetMed, DZooMed, MRCVS' 'Exotic Animal, Wildlge and Zoological Medicine, Department of Small Animal Medicine and Surgery, College of Veterinary Medicine, University of Georgia, Athens, GA 30602 USA; 'Department of Small Animal Clinical Sciences, College of Veterinary Medicine, The University of Tennessee, Knoxville, TN 3 7996 USA; 'Anesthesiology, Department of Small Animal Medicine and Surgery, College of Veterinary Medicine, University of Georgia, Athens, GA 30602 USA; 'Eastern Exotics Center, 4001 Legato Road, Fairfa, VA 22033 USA Abstract Twenty-three, male captive-bred green iguanas (Iguana iguana) weighing 0.5 1-0.67 kg were anesthetized to determine the effectiveness and the cardiopulmonary effects of butorphanol- sevoflurane and butorphanol-isoflurane. Baseline heart and respiratory rates were recorded on all animals prior to administration of intramuscular butorphanol (2 mgikg). Thirty minutes after premedication, the heart rate and respiratory rate of each iguana was recorded and 12 animals were induced with isoflurane (5% in 100% oxygen), and 11 were induced with sevoflurane (8% in 100% oxygen), via face mask. Following the loss of the righting reflex, each iguana was intubated and intermittent positive pressure ventilation (IPPV) was provided at 10-12 breathdmin with a small animal ventilator. Mean maintenance isoflurane and sevoflurane concentrations were 2% and 4%, respectively. Heart rate, functional oxygen hemoglobin saturation (SpO,), and end-tidal CO, concentrations were measured every 5 min. The presence or absence of the righting, palpebral, and foot withdrawal reflexes were recorded to judge anesthetic depth. Arterial blood gases (pH, PO,, PCO,) were determined at 10 and 30 min following induction. In both groups, anesthesia was maintained for an average of 45 min. Inductions with butorphanol-sevoflurane(6.0 f 3.0 min; mean f S.D.) were smoother and significantly shorter than with butorphanol-isoflurane (9.0 f 4.0 min). During maintenance of anesthesia, cardiopulmonary parameters were well maintained in both groups. In both groups pulse oximeter readings (SpO,) were < 90% during the first 5 min of anesthesia, indicating potential hypoxemia. For the remainder of the anesthetic period SpO, values were > 90%. End-tidal CO, concentrations were between 20-40 mm Hg during the first 5 rnin of anesthesia and decreased to a range between 15-20 mm Hg for the remainder of the anesthetic event. No significant differences in heart rate, oxygen hemoglobin saturation, and end-tidal CO, concentrations were noted between the two groups. Mean recovery time was significantly longer (35.0 f 27.0 min) in the butorphanol-isoflurane group than in the butorphanol-sevoflurane group (7.0 f 4.0 min). In conclusion, the cardiopulmonary effects of butorphanol-isoflurane and butorphanol-sevoflurane were similar, however quality and speed of induction and recovery was significantly shorter with sevoflurane when compared to isoflurane. 2003 PROCEEDINGS AMERICAN ASSOCIATION OF ZOO VETERINARIANS 1 OUTBREAK OF WEST NILE VIRUS IN FARMED ALLIGATORS (Alligator mississippiensis) IN FLORIDA Elliott R. Jacobson,' * J. Mitchell Troutman,' Pamela Ginn,' Jorge Hernandez,' Lillian Stark,' Robert Stephens,' Nick K~mar,~and Michael L. Bunning4 'College of VeterinaryMedicine, University of Florida, Gainesville, FL 3261 0 USA;' Florida Department of Health Bureau of Laboratories, Tampa, FL 33612 USA;3West Orange Veterinary Hospital, Winter Garden, FL 34 78 7 USA;4Divisionof Vector-BorneInfectious Diseases, Centersfor Disease Control and Prevention, Fort Collins, CO 80522-2089 USA Abstract In September and October 2002, an epizootic characterized by neurologic disease occurred at a 9,000-alligator farm in Florida. Approximately 300 alligators (Alligator mississippiensis) died during this time. First cases were observed in 1-m long yearlings on 15 October 2002. Three animals were clinically evaluated and exhibited a range of signs that included depression, lethargy and signs of neurologic disease. They were euthanatized and necropsies were performed. Gross lesions consisted of mild coelomic effusions, fibrinonecroticoral mucosal exudates, and enlarged pale livers with red mottling. The most significant microscopic lesions were a moderate heterophilic to lymphoplasmacytic meningoencephalomyelitis, necrotizing hepatitis and splenitis, myocardial degeneration with necrosis, mild interstitial pneumonia, hepatic lipidosis, adrenalitis, and heterophilic necrotizing stomatitis, and glossitis. Examination of the brain and other tissues was conducted using an immunoperoxidase staining technique and a monoclonal antibody for West Nile virus (WNV) antigen. Positive staining was demonstrated in the brain as well as other tissues. Portions of brain, spinal cord, and other tissues were submitted both to the Florida Department of Health Bureau (FDHB) of Laboratories in Tampa and to the Division of Vector-Borne Infectious Diseases, Centers for Disease Control and Prevention (CDC) in Ft. Collins, Colorado, for definitive diagnosis of WNV. Virus was isolated, and polymerase chain reaction (PCR) testing confirmed the presence of WNV. This was the first identification of WNV in a reptile. 2 2003 PROCEEDINGS AMERICAN ASSOCIATION OF ZOO VETERINARIANS ENDOSCOPIC EVALUATION OF THE AMERICAN ALLIGATOR (Alligator mississippiensis) RESPIRATORY TRACT Maud Lafortune, DMV, MSc,,'* Thomas Gobel, DMV,' Elliot Jacobson, D VM, PhD, Dip1 ACZM,,' Dan Brown, MS, PhD,:' Rick Alleman, DVM, PhD, ADCVP, ABVP,,'Kent Wet,PhD,' and Jorge Hernandez, DVM, MPVM, PhD' Department of 'Small Animal Clinical Sciences and 'Large Animal Clinical Sciences, College of Veterinary Medicine, University of Florida, Gainesville, FL 3261 0 USA; 'Small and Exotic Animal Practice, Mecklenburgische Strasse 2 7, D-1419 7 Berlin, Germany; :'MycoplasmaResearch Laboratory, Department of Pathobiology, and 'Institute of Zoology, University of Florida, Gainesville, FL 32610 USA Abstract Respiratory diseases are common in captive and wild American alligators (Alligator mississippiensis), but are difficult to diagnose ante-mortem. Bronchoscopy permits direct visualization of the respiratory tract and sample collection, but cytologic and microbiologic reference values are lacking for crocodilians. Twelve (three males and nine females) 3-yr-oldY1-m long, 4.5-9.0-kg captive-born alligators were used in this study. Bronchoscopy, using a flexible endoscope (3.3 x 700 mm choledochofiberscope OES, Olympus, Hamburg, Germany), was used to separate the alligators into two groups. The criterion for separating them was the absence or presence of respiratory inflammation, mucous, blood, secretions, parasites and/or masses. Six alligators without any abnormalities were placed in Group A. The other six alligators had respiratory lesions and were placed into Group B. Endoscopy was repeated every 3 mo for 12 mo. A tracheal wash (at the bronchial bifurcation) was collected each time an alligator was evaluated and submitted for Mycoplasma spp., aerobic, and fungal cultures. Microscopic slides were prepared for cytologic examination. Mycoplasma spp. were not isolated from any animal. Low numbers of samples (1 1 out of 48; 23%) resulted in scant growth of bacterial colonies. Similarly, low numbers of samples (9 out of 48; 19%) resulted in scant growth of fungal agents. These organisms were considered to be nonpathogenic and likely the result of oral contamination. Cytologic evaluation of collected material found most samples (90%) contained only a small amount of mucus, low numbers of ciliated columnar epithelium and keratinized squamous cells. Less than 10% of the samples contained large amounts of mucus, reactive macrophages or heterophils, which would be considered evidence of irritatiodinflammation to the airways. No bacteria or parasites were observed in any of the samples. ACKNOWLEDGMENTS This research project was supported by the St. Augustine Alligator Farm fund. The assistance of Darryl Heard, Jeff Davidson, Jennifer Long, Heiko Shultze, Kelly Daigle, Alexander Valverde, Jean Pare, Hendrik Nollens, April Johnson, Ian Bessel and University of Florida veterinary students is also gratefully acknowledged. 2003 PROCEEDINGS AMERICAN ASSOCIATION OF ZOO VETEFUNARIANS 3 HEALTH ASSESSMENT IN THE EASTERN INDIGO SNAKE (Drymarchon corais couperi) IN SOUTHEASTERN GEORGIA: PRELIMINARY FINDINGS Terry M. Norton, DVM, DiplACZM,,'* Robert Poppenga, D VM, PhD,' Elliot Jacobson, DVM, PhD, Dip1 ACZM,,' Dirk Steven~on,~Carolyn Cray, PhD, 'Ellen Dierenfeld, PhD,6 Maria S. Sepulveda, DVM, PhD,' Timothy Gross, PhD,7 Tai Chen, PhD,8 Sam Telfrd, DVM, PhD,9 and Marcie Oliva'O I Wildlife Conservation Society, St. Catherines Wildlife Survival Center, Midway, GA 31320 USA; 'University of Pennsylvania, Laboratory ofLarge Animal Toxicology, New Bolton Center, Kennett Square, PA 19348 USA; 'University of Florida, Department of Small Animal Clinical Sciences, College of VeterinaryMedicine, Gainesville,FL 3261 0 USA; 4Ft.Stewart Fish and Wildlife Branch, Ft. Stewart, GA 31314-4940 USA; 'University of Miami, Department of Patholow, PO Box 01690 (R-46), Miami, FL 3261 0 USA; Wildlife Conservation Society, Department of Nutrition, 21 00 Southern Blvd, Bronx,