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CORNEAL VASCULARIZATION in the FLORIDA MANATEE (Trichechus Manatus Latirostris)

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CORNEAL VASCULARIZATION in the FLORIDA MANATEE (Trichechus Manatus Latirostris) CORNEAL VASCULARIZATION IN THE FLORIDA MANATEE (Trichechus manatus latirostris) By JENNIFER YOUNG HARPER A DISSERTATION PRESENTED TO THE GRADUATE SCHOOL OF THE UNIVERSITY OF FLORIDA IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY UNIVERSITY OF FLORIDA 2004 Copyright 2004 by Jennifer Young Harper ACKNOWLEDGMENTS I would like to thank my mentor, Dr. Don Samuelson. He has been a wonderful source of knowledge, inspiration, and motivation. Without his help and guidance, I could not have accomplished any of this work. I would also like to thank Dr. Roger Reep for all of his help and support along the way. He too has acted as a rock and support system. My additional committee members (Dr. Peter McGuire, Dr. Dennis Brooks, and Dr. Gordon Bauer) have been tremendous support and I thank them for all they have offered. Their guidance has been appreciated beyond belief. Laboratory technologists Pat Lewis and Maggie Stoll were extremely helpful and supportive during much of my work. I would have not been able to accomplish the first procedure without their help. I thank these fine ladies from the bottom of my heart. My parents, Jim and Marion Young, have meant more to me than I can ever describe or explain. I appreciate all their love and support. Finally, I thank my husband Ridge Harper. He has been the strongest support system I could ever ask for and makes me happier than I ever knew I could be. iii TABLE OF CONTENTS page ACKNOWLEDGMENTS ................................................................................................. iii LIST OF TABLES............................................................................................................. vi LIST OF FIGURES .......................................................................................................... vii ABSTRACT.........................................................................................................................x CHAPTER 1 LITERATURE REVIEW .............................................................................................1 The Florida Manatee.....................................................................................................1 The Tactile Sensory System of Marine Mammals .......................................................2 The Auditory System of Marine Mammals..................................................................5 The Olfaction and Gustation of Marine Mammals.......................................................7 The Vision of Marine Mammals...................................................................................8 The Cornea..................................................................................................................13 Angiogenesis...............................................................................................................17 Objectives ...................................................................................................................22 2 CORNEAL VASCULARIZATION IN THE FLORIDA MANATEE AND THREE-DIMENSIONAL RECONSTRUCTION .....................................................23 Introduction.................................................................................................................23 Materials and Methods ...............................................................................................32 Specimen Collection............................................................................................32 Results.........................................................................................................................36 Anatomical Description.......................................................................................36 Morphometry.......................................................................................................39 Statistics...............................................................................................................40 Discussion...................................................................................................................42 3 VASCULAR ENDOTHELIAL GROWTH FACTOR RECEPTOR-1 AND -2 IN THE FLORIDA MANATEE CORNEA ....................................................................96 Introduction.................................................................................................................96 Materials and Methods .............................................................................................106 iv Specimen Collection..........................................................................................106 Preparation of Eyes............................................................................................106 Histology ...........................................................................................................107 Immunohistochemistry......................................................................................107 Results.......................................................................................................................108 Vascular endothelial growth factor receptor-1 (VEGFR-1)..............................108 Vascular endothelial growth factor receptor-2 (VEGFR-2)..............................109 4 ADDITIONAL STUDIES........................................................................................127 Corneal Vascularization in the Antillean Manatee...................................................127 Ophthalmic Examinations in Two Captive Florida Manatees..................................128 5 GENERAL CONCLUSIONS...................................................................................139 LIST OF REFERENCES.................................................................................................142 BIOGRAPHICAL SKETCH ...........................................................................................154 v LIST OF TABLES Table page 2-1 Information on manatee tissue used and volume of vasculature at 25 X.................41 2-2 Volume of vasculature at 200 X...............................................................................42 vi LIST OF FIGURES Figure page 2-1 Florida manatee eye with ocular tissue and fat removed revealing the eye and optic nerve..............................................................................................................55 2-2 Histological pictures of MNW-9111 .....................................................................56 2-3 These pictures were taken of MSW-9114 of the same blood vessel at varying magnifications to show the penetration of this vessel into the anterior epithelium ..............................................................................................................57 2-4 UCF-9114 shows the smaller vessels that were outlined within the stroma for three-dimensional reconstruction (200X). .............................................................58 2-5 Pictures from MNW-9016 .....................................................................................59 2-6 These pictures were taken from the unknown specimen. (A) Shows the edge of the limbal vascular arrangement at the peripheral cornea (200X), and (B) larger vessels that go right up to the anterior epithelium at 200X. ..................................60 2-7 Anatomical orientation of manatee eyes as they are described in three- dimensional reconstruction ....................................................................................61 2-8 MNW-9016............................................................................................................62 2-9 MNW-9022(R).......................................................................................................63 2-10 MNW-9111............................................................................................................64 2-11 MNW-9116............................................................................................................65 2-12 MSE-9101..............................................................................................................66 2-13 MSE-9105..............................................................................................................67 2-14 MSE-9107..............................................................................................................68 2-15 MSE-9115..............................................................................................................69 2-16 MSE-9131..............................................................................................................70 vii 2-17 MSW-9114.............................................................................................................71 2-18 MSW-9131(R). ......................................................................................................72 2-19 MSW-9137(L)........................................................................................................73 2-20 MSW-9137(R). ......................................................................................................74 2-21 MSW-9141.............................................................................................................75 2-22 MSW-9143.............................................................................................................76 2-23 TM-8619(L). ..........................................................................................................77 2-24 TM-8619(R)...........................................................................................................78
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