Louisiana State University LSU Digital Commons LSU Doctoral Dissertations Graduate School 2007 Lymphohistiocytic Proliferative Syndrome of Alligators (Alligator mississippiensis): a cutaneous manifestation of West Nile virus Javier G. Nevarez Louisiana State University and Agricultural and Mechanical College, [email protected] Follow this and additional works at: https://digitalcommons.lsu.edu/gradschool_dissertations Part of the Veterinary Medicine Commons Recommended Citation Nevarez, Javier G., "Lymphohistiocytic Proliferative Syndrome of Alligators (Alligator mississippiensis): a cutaneous manifestation of West Nile virus" (2007). LSU Doctoral Dissertations. 3521. https://digitalcommons.lsu.edu/gradschool_dissertations/3521 This Dissertation is brought to you for free and open access by the Graduate School at LSU Digital Commons. It has been accepted for inclusion in LSU Doctoral Dissertations by an authorized graduate school editor of LSU Digital Commons. For more information, please [email protected]. LYMPHOHISTIOCYTIC PROLIFERATIVE SYNDROME OF ALLIGATORS (ALLIGATOR MISSISSIPPIENSIS): A CUTANEOUS MANIFESTATION OF WEST NILE VIRUS A Dissertation Submitted to the Graduate Faculty of the Louisiana State University and Agricultural and Mechanical College in fulfillment of the requirements for the degree of Doctor of Philosophy in The Interdepartmental Program in Veterinary Medical Sciences through the Department of Veterinary Clinical Sciences by Javier G. Nevarez B.S., Louisiana State University, 1998 D.V.M., Louisiana State University, 2001 May 2007 To the gators. ii ACKNOWLEDGEMENTS This project would not have been possible without the efforts of multiple individuals and organizations that supported me either intellectually, spiritually, or financially. The end product is a prime example of what can be accomplished when people from different backgrounds work together towards a common goal. I would like to thank my mentor and friend for over 11 years, Dr. Mark A Mitchell, who has guided my professional and personal growth. This project was just one of many amazing opportunities I had to work with a unique reptile species alongside Dr. Mitchell. I will always be indebted to him for his guidance, patience and understanding. I also have to thank Dr. Thomas N. Tully for his friendship and mentorship. Dr. Tully has also contributed to my professional and personal growth by opening a world of opportunities for me within the exotic animal service at the LSU School of Veterinary Medicine. I will always consider both of them the two most influential people in my veterinary career. In addition, I would like to thank the other members of my committee, Drs. John Hawke, Gary Sod, and Lane Foil. Their diverse background and expertise was instrumental in making this project a successful one and making me consider all angles of a research project. Thank you for your mentorship, and know that I am a better person and a better veterinarian thanks to your teachings. Other major contributors to this project include Drs. Timothy Morgan, Michael Garner, April Johnson, Dr. Peter Jowett and Alma Roy. Dr. Roy and her staff at the Louisiana Veterinary Medicine Diagnostic Laboratory, Rob Poston, Tarra Harden, Heather Lampinen, Dr. Alejandra Baudena, Dr. Kim Bowles, and Durriya Sarkar, were one of the most professional groups of people I have had the opportunity to work with during the project. Their hard work, commitment, and proficiency are acknowledged and appreciated. An additional group that revealed the professionalism that is present at the university was the histology laboratory iii personnel, Mr. Hal Holloway, Cheryl Crowder, and Julie Millard. Their input and guidance was also instrumental in ensuring a sound research project. I would also like to thank the administration and faculty from the department of Veterinary Clinical Sciences, and more specifically Dr. David Senior, Mrs. Jackie Bourgeois, Mrs. Jackie Murray for their hard work and support. A special thanks to Shelly Lyles, Randy Nehlig, and Marlana Roundtree for their assistance during certain phases of the project. I must express a special gratitude to Dr. April Johnson who in the middle of her own dissertation project graciously performed the WNV ELISA tests so needed for this project. This project would not have been possible without the financial support of the Louisiana Department of Wildlife and Fisheries, Fur and Refuge Division. Mr. Noel Kinler and Mrs. Ruth Elsey provided knowledge and support that was indispensable for making this project a reality. The Louisiana Alligator Council, the Louisiana Alligator Association, and all the Louisiana Alligator producers also contributed significantly to this project. I would like to thank Mr. Jeff Donald, Dane Ledet, and Jerry Savoie for their support. It was Mr. Ledet who originally identified an association between WNV and LPSA in his facility. Without his keen sense of observation it would have taken a longer time to complete the study. Friends and family are always a big part of the support net that one must rely upon to be successful in life. In my case I was lucky to have such a network to guide me through the completion of the project. To my friends Jason Blackburn and Mary-Claire Blackburn, thank you for the meals and lodging during the times of field work. To my family, thank you for always believing in me and supporting my endless educational endeavors. Finally, and most importantly, thank you to my wife Emily for her help during the project and her patience when I was writing and had little patience with those around me. I must also acknowledge all the living creatures in our house, Sophie, Eddie, Soleil, Sid, Daisy, and the Skinks for accepting me iv regardless of my mood and making me laugh when I needed it the most. The success of this work is shared with all of you. v TABLE OF CONTENTS DEDICATION................................................... ............ ii ACKNOWLEDGEMENTS...................................... ............... .iii ABSTRACT............................................ ................... viii INTRODUCTION............................................. ................ 1 LITERATURE REVIEW ............................ ........... ................4 Louisiana Alligator Industry . .4 Taxonomy . ...............................6 Anatomy and Physiology . ...............6 Husbandry . ................... .12 Nutrition.......................................................... 15 Preventive Medicine . ........................... .16 Handling and Restraint . .18 History and Physical Examination . ....................... 19 Diagnostic Testing . 21 Stress and Immunosuppression . ................ ..... .24 BacterialDiseases................................... ..... .26 Viral Diseases . ....................................... .31 FungalDiseases.................................................... 35 Parasitic Diseases . ........................................... 36 NutritionalDiseases................................................. 38 RespiratoryDiseases................................................. 40 NeurologicDiseases................................................. .. ..40 Musculoskeletal Diseases . 41 Gastrointestinal Diseases . .... 42 IntegumentaryDiseases.............................................. 43 Toxicities........................................................ .. 45 Runting........................................................... 46 WestNileVirusHistory.................................... .. .. 46 CHAPTER 1. LYMPHOHISTIOCYTIC PROLIFERATIVE SYNDROME OF ALLIGATORS: PRELIMINARY INVESTIGATION .............................. .55 Introduction . ............................... 55 Materials and Methods . 56 Results ............ ..................................... 60 Discussion .............................................. .68 CHAPTER 2. WEST NILE VIRUS IN ALLIGATOR, ALLIGATOR MISSISSIPPIENSIS, RANCHES FROM LOUISIANA....................................... ..........72 Introduction . ................ 72 Materials and Methods . 73 Results ............................ ..................... 79 Discussion .............................................. .81 vi CHAPTER 3. ESTABLISHING AN ASSOCIATION BETWEEN WEST NILE VIRUS SEROPOSITIVITY AND THE DEVELOPMENT OF LYMPHOHISTIOCYTIC PROLIFERATIVE SYNDROME OF ALLIGATORS .......... ....... .......... 85 Introduction . .............. 85 Materials and Methods . 86 Results .............................. ................... 88 Discussion .............................................. .88 CHAPTER 4: LYMPHOHISTIOCYTIC PROLIFERATIVE SYNDROME OF ALLIGATORS: A CUTANEOUS MANIFESTATION OF WEST NILE VIRUS ........................ 90 Introduction...... ....................................... 90 Materials and Methods . 91 Results ................................................. ........... .. .93 Discussion .............................................. .95 CHAPTER: 5 PREVENTION, SURVEILLANCE, AND CONTROL METHODS FOR WNV IN ALLIGATOR RANCHES.......... .... .......... .......... ... .......... .98 Introduction...... ....................................... .98 Prevention ............... ..................... ........ .98 Surveillance................................................. 101 Control ........ ..................................... ... 105 Discussion .............................................. .109 CONCLUSIONS.............................................. 111 REFERENCES.............................................. ............. 118 APPENDIX: LETTER OF PERMISSION