STUDIES ON CHARACTERIZATION OF MEMBERS OF TWO FISH GENERA, hydrocynus and Alestes, FROM THE WHITE NILE AND LAKE NUBIA By HAMID AHMAD MARGANI AWAD B. Sc. (HONOURS), SUDAN UNIVERSITY, ANIMAL PRODUCTION, 1996 A THESIS SUBMITTED TO THE DEPARTMENT OF ZOOLOGY IN FULFILLMENT OF THE REQUIRMENTS FOR THE DEGREE OF M. Sc. DEPARTMENT OF ZOOLOGY, FACULTY OF SCIENCE, UNIVERSITY OF KHARTOUM October 2006 © Hamid Margani DEDICATION TO MY LATE FATHER TO MY LATE MOTHER TO MY FAMILY AND TO MY FRIENDS ACKNOWLEDGEMENTS My thanks and grate appreciation are due to my supervisor Dr. Sumaia Mohamed Ahmed Abukashawa who encouraged me and whose keen guidance, valuable advice and patience throughout the period of this work made the essence for its accomplishment. In her person, I thank all the staff members of the Zoology Department, University of Khartoum, for their help and for offering the facility of the Genetics Lab. I would like to express special thanks to Professor Yousif Babikir Abu Gidieri, Zoology Department, for his interest in this work and his valuable advice. His willingness to share his experience and expertise was a tremendous help to me. Thanks are extended to Dr. Zuhair Nur Eldaim for his advice and support. I am grateful to my colleagues and friends who took the time to make suggestions for improvement of this work and for their encouragement and support. Thanks are extended to the Animal Resources and Research, Ministry of Science and Technology for sponsoring my study. CONTENTS Page DEDICATION I ACKNOWLEDGEMENTS ii CONTENTS iii LIST OF TABLES v LIST OF FIGURES vii ABSTRACT x ARABIC ABSTRACT xii CHAPTER ONE 1 INTRODUCTION AND LITERATURE REVIEW 1.1 GENERAL INTRODUCTION 1 1.2 FISHES OF THE NILE 1 1.2.1 Lake Nubia 3 1.3 TAXONOMIC RELATIONSHIPS 3 1.3.1 The Genus Hydrocynus 6 1.3.1.1 Hydrocynus forskalii 6 1.3.1.2 Hydrocynus brevis 6 1.3.1.3 Hydrocynus lineatus 7 1.3.2.1 Alestes dentex 8 1.3.2.2 Alestes baremose 8 1.3.2.3 Alestes nurse 9 1.3.2.3 Alestes macrolepedidotus 9 1.4 CYTOGENETIC STUDIES 10 1.4.1 Chromosomes and karyotypes 10 1.4.2 Fish karyotypes 12 1.5 PROTEIN STUDIES 15 1.6 OBJECTIVES OF THE SUDY 17 CHAPTER TWO: MATERIALS AND METHODS 19 2.1. SAMPLE COLLECTION 19 2.2. MORPHOMETRIC MEASUREMENTS 19 2.3 STATISTICAL ANALYSIS 20 2.3 KARYOTYPING 22 2.4 PROTEIN ELECTROPHORESIS 23 2.4.1 Preparation of The Reagents Of SDS- Polyacrylamide Gel 23 2.4.2 Pouring SDS-Polyacrylamide Gels 26 2.4.3 Preparation Of The Samples 27 2.5 STATITICAL ANALYSIS 29 CHAPTER THREE: RESULTS 30 3.1 THE SPECIES 30 3.2 MORPHOMETRIC MEASUREMENTS 35 3.3 CYTOGENETIC DATA 68 3.4 PROTEIN POLYMORPHISM 84 CHAPTER FOUR: DISCUSSION AND CONCLUSIONS 90 4.1 DISCUUSION 90 4.2 CONCLUSION AND RECOMMENDATIONS 93 REFERENCES 95 APPENDICES: 101 APPENDIX 1: ABREVIATIONS APPENDIX 2: GLOSSARY LIST OF TABLES Table Page Table (I): Morphometric measurements and ratios of Alestes baremose from Lake Nubia 37 Table (II): Morphometric measurements and ratios of Alestes baremose from Jebel Aulia 38 Table (III): Morphometric measurements and ratios of Alestes dentex from Lake Nubia 39 Table (IV): Morphometric measurements and ratios of Alestes dentex from Jebel Aulia 40 Table (V): Morphometric measurements and ratios of Alestes nurse from Lake Nubia 41 Table (VI) Morphometric measurements and ratios of Alestes nurse from Jebel Aulia 42 Table (VII): Morphometric measurements and ratios of Alestes macrolepidotus 43 Table (VIII): Morphometric measurements and ratios of Hydrocynus lineatus from Lake Nubia 44 Table (IX): Morphometric measurements and ratios of Hydrocynus lineatus from Jebel Aulia 45 Table (X): 46 Morphometric measurements and ratios of Hydrocynus bevies from Lake Nubia Table (XI): Morphometric measurements and ratios of Hydrocynus brevis from Jebel Aulia 47 Table (XII): Morphometric measurements and ratios of Hydrocynus forskalii from Lake Nubia 48 Table (XIII): Morphometric measurements and ratios of Hydrocynus forskalii from Jebel Aulia Table(XIV): Comparisons of means and standard error of morphometric measurements for Alestes 51 Table (XV): Comparisons of means and standard error of morphometric measurements for Hydrocynus 52 LIST OF FIGURES Figure Page Figure (1). Map of collection sites 21 Figure (2). Diagram of Hydrocynus and Alestes measurements 32 Figure (3). Photograph of Hydrocynus forskalii Figure (4). Photograph of Hydrocynus lineatus 32 Figure (5). Photograph of Hydrocynus brevis 33 Figure (6). Photograph of Alestes baremose 33 Figure (7). Photographs of Alestes dentex 33 Figure (8). Photograph of Alestes nurse 34 Figure (9). Photograph of Alestes macrolpedotus 34 Figure (10). Morphometric relationships in Alestes nurse 55 a: Relationship between length & depth 55 b: Relationship between standard length & depth 55 c: Relationship between inter orbital width & eye diameter 56 d: Relationship between peduncle length & peduncle depth 56 57 Figure (11). Morphometric relationships in Alestes baremose: a: Relationship between depth & length 57 b: Relationship between depth & standard length 57 c: Relationship between inter orbital width &eye diameter 58 d: Relationship between peduncle length & peduncle depth 58 59 Figure (12). Morphometric relationships in Alestes dentex a: Relationship between length & depth 59 b: Relationship between standard length & depth 59 c: Relationship between eye diameter & inter orbital width 60 d: Relationship between peduncle length & peduncle width 60 Figure (13). Morphometric relationships Hydrocynus lineatus 61 a: Relationship between length & depth 61 b: Relationship between standard length & depth 61 c: Relationship between eye diameter & inter orbital width 62 d: Relationship between peduncle length & peduncle width 62 Figure (14). Morphometric relationship between in Hydrocynus forskalii 62 a: Relationship between length & depth 62 b: Relationship between standard length & depth 62 c: Relationship between eye diameter & inter orbital width 63 d: Relationship between peduncle length & peduncle width 63 Figure (15). Morphometric relationship in Hydrocynus brevis a: Relationship between length & depth 66 b: Relationship between standard length & depth 66 c: Relationship between eye diameter & inter orbital width 67 d: Relationship between peduncle length & peduncle width in 67 Figure (16): Prophase of Hydrocynus brevis in Jebel Aulia 70 Figure (17): Late prophase of Hydrocynus brevis in Lake Nubia 70 Figure (18): Metaphase of Hydrocynus brevis in Jebel Aulia 71 Figure (19): Metaphase of Hydrocynus lineatus in Lake Nubia 71 Figure (20): Interphase of Hydrocynus brevis in Lake Nubia 72 Figure (21): Telophase of Hydrocynus lineatus in Lake Nubia 72 Figure (22): Metaphase of Alestes baremose in Jebel Aulia 73 Figure (23): Metaphase of Alestes baremose in Jebel Aulia.73 73 Figure (24): Late Anaphase of Hydrocynus brevis in Jebel Aulia 74 Figure (25): Metaphase of Hydrocynus brevis in Jebel Aulia 74 Figure (26): Anaphase of Alestes baremose in Jebel Aulia 75 Figure (27) : Anaphase of Alestes dentex in Lake Nubia 75 Figure (28): Late prophase of Alestes dentex in Jebel Aulia 76 Figure (29): Metaphase of Alestes dentex in Lake Nubia 76 Figure (30): Early prophase of Hydrocynus brevis in Lake Nubia 77 Figure (31): Anaphase of Alestes dentex in Jebel Aulia 78 Figure (32): Anaphase of Alestes baremose in Lake Nubia 78 Figure (33): Metaphase of Hydrocynus brevis in Lake Nubia 79 Figure (34): Metaphase of Hydrocynus brevis in Jebel Aulia 79 Figure (35): Prophase of Hydrocynus lineatus in Jebel Aulia 80 Figure (36): Metphase of Hydrocynus forskalii 80 Figure (37): Late prophase of Hydrocynus 81 Figure (38): Late Anaphase of Hydrocynus 81 Figure (39): Metaphase of Hydrocynus lineatus 82 Figure (40): Ideogram of karyotype of Hydrocynus 83 Figure (41): Ideogram of karyotype of Alestes 84 Figure (42): Electrophoresis band of the soluble liver protein of Hydrocynus and Alestes collected from Lake Nubia 85 Figure (43): Electrophoresis band of the soluble liver protein of Hydrocynus and Alestes collected from Jebel Aulia 85 Figure (44): Electrophoresis band of the soluble muscle tissues protein of Hydrocynus and Alestes collected from Jebel Aulia 86 Figure (45): Electrophoresis band of the soluble liver protein of Hydrocynus and Alestes collected from Lake Nubia 86 Figure (46): Electrophoresis band of the soluble muscle tissues protein of Hydrocynus and Alestes collected from Lake Nubia 87 Figure (47): Comparison between two different populations of Alestes dentex in Lake Nubia and Jebel Aulia 87 Figure (48): Comparison between two different populations of Alestes baremose in Lake Nubia and Jebel Aulia 88 Figure (49): Comparison between two different populations of Hydrocynus brevis in Lake Nubia and Jebel Aulia 89 ABSTRACT Members from species of two genera of the Nile fishes Hydrocynus and Alestes were collected from Lake Nubia at Wadi Halfa and from Jebel Aulia at the White Nile. Collection was done during the period from May 2001 to March 2005. Eight species were studied for morphometric measurements and ratios, cytogenetic patterns and protein polymorphism. Morphometric measurements taken included the total length (L), standard length (SL), depth (D), interorbital width (IOW), eye diameter (ED), peduncle length (PL) and peduncle depth (PD). Measurements and ratios revealed significant differences between members of the species collected at the two freshwater systems. The cytogenetic study revealed a chromosome complement of 2n= 56 for Hydrocynus species members and 2n= 42 for Alestes species members. Chromosomes were found to vary in structure within