GROWTH AND SPAWNING OF FURCOSUS IN THE COASTAL WATER OF PAHANG, MALAYSIA

BY

AMIRA FARZANA BINTI SAMAT

A thesis submitted in fulfilment of the requirement for the degree of Master of Science (Bioscience)

Kulliyyah of Science International Islamic University Malaysia

NOVEMBER 2014

ABSTRACT

Nemipterus furcosus, commonly known as fork-tail is an economically important food in Malaysia but the capture production of this fish is decreasing gradually in the Malaysian water. However, nothing is known about the population of this species in the Malaysian water especially in the coastal of Pahang. Therefore, this study aimed to understand some important characteristics of fork-tail threadfin bream population in the coastal water of Pahang. Monthly samples were collected from commercial fishing trawlers for a period of one year (August 2012 - July 2013). A total of 1599 threadfin bream specimens were studied in this research. The results showed that male threadfin bream was significantly more than female (p<0.01) in the population of Pahang coastal water. The mathematical relationship between length and weight of fork-tail threadfin bream of each month was significant (p<0.05) with all coefficients of determination (R2) values being higher than 0.7799 for male, while 0.5091 for female. The growth coefficient (b value) varied between 2.6808 (May) and 3.333 (October) for male and 2.0926 (September) and 3.2464 (November) for female N. furcosus. A negative allometric growth of N. furcosus was observed from February until June, and September for female while in January, March until June, and November for male N. furcosus. Positive allometric growth was observed in remaining month of both male and female N. furcosus. The growth coefficients were very low in September for female and in May for male compared to other months. The significantly (P<0.05) lowest mean condition factor was found in July (1.2559) and the highest in August (1.3917) for male while lowest in March (1.2503) and highest in August (1.3926) for female N. furcosus. Overall higher mean condition factor was observed in smaller fish of both sexes. The overall mean condition factor of male and female was statistically similar (p>0.05). Mean gonadosomatic index (GSI) of female was higher than male in all months. GSI of female N. furcosus was highest in June while male in November. Gonadosomatic index of female rapidly increased after December and reached at peak in June and decline after June. Histological observation of gonads also showed reasonably similar stages of maturation in both male and female. N. furcosus showed immature gonadal stage in October and November. After that, they enter the maturing stage in December, January and February and mature in March. After the mature stage, N. furcosus testes and ovaries enter the ripe and running stage in April, May, June and July. Then, the gonad spent in August and finally enters the resting stage in September. The spawning season of threadfin bream in Pahang coastal water was from January to August. Histological study indicated that the peak spawning season occurs from April to July. This study indicated that the histological study is very useful to understand the peak spawning period of fish. The results of the study will help the management of juvenile and breeding N. furcosus stock in order to maintain sustainable exploitation in the coastal water of Pahang.

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خالصة البحث ABSTRACT IN ARABIC

ِ )( أبرميس ذو زعانف َسليكية وُزلََّززة هي األمساك الغذائية اذلامة اقتصاديا يف ماليزيا إال أن اإلنتاج السمكي ينخفض تدريجيا في املياه املاليزية. علىالرغم من ذلك، ال نعرف شيء عن التجمع السمكي ذلذا النوع من السمك يف ادلياه ادلاليزية والسيما يف ادلناطق الساحلية بوالية باهانغ. وبالتايل، فإن هذا البحث هدفي إىل فهم بعض اخلصائص ادلهمة للتجمع السمكي ألبرميس ذو زعانف ِ )Nemipterus furcosus( َسليكية وُزلََّززة يف ادلياه الساحلية من والية باهانغ. قد مت مجع عينات شهرية من سفن الصيد التجارية دلدة سنة واحدة )من أغسطس 2102 إىل يوليو (.2102 ومتت دراسة رلموعة من 0488 عينة أبرميس ذو زعانف يف هذا البحث. وأظهرت النتائج أن ذكور أبرميس ذو زعانف كان أكثر بكثري من اإلناث (p<0.01) يف التجمع السمكي من ادلياه الساحلية بوالية باهانغ. وكانت ِ ٍ (p<0.05) العالقة الرياضية بني طول ووزن أبرميس ذو زعانف َسليكية وُزلََّززة يف كل شهر ذو داللة َملحوظة مع مجيع قيم معامالت التحديد 2 ( R) وهي أكثر من 1،6688 للذكور، يف حني 1،4180 لإلناث. معامل النمو )قيمة ب( تفاوتت بني 2،5717 )مايو( ِ ) Nemipterus و2،2222 )أكتوبر( للذكور و2،1825 )سبتمرب( و 2،2353 )نوفمرب( إلناث أبرميس ذو زعانف َسليكية وُزلََّززة Nemipterus furcosus( ِ furcosus (. ومن ادللحوظ، وجود متفاوت النمو السلبية ألبرميس ذو زعانف َسليكية وُزلََّززة ( يف فرتة ما بني ِ ) Nemipterus شهر فرباير حىت يونيو وسبتمرب لإلناث وأما يف يناير ومارس حىت يونيو، ونوفمرب لذكور أبرميس ذو زعانف َسليكية وُزلََّززة furcosus. ِ ( ومن ادللحوظ أيضا، متفاوت النمو اإلجابية يف الشهور ادلتبقية من ذكور وإناث أبرميس ذو زعانف َسليكية وُزلََّززة )Nemipterus furcosus(. فمعامالت النمو كانت منخفضة جدا يف شهر سبتمرب لإلناث والذكور يف شهر مايو مقارنة بالشهور األخرى. ومت العثور على ادلعنوي (P<0.05) أدىن معامل متوسط احلالة يف شهر يوليو ) ( 0،2448وأعاله يف شهر أغسطس )0،2806( ِ للذكور بينما أدىن مستوى يف شهر مارس ) (0،2412 وأعلى مستوى يف شهر أغسطس )0،2825( إلناث أبرميس ذو زعانف َسليكية Nemipterus furcosus( وُزلََّززة (. وارتفع معامل طمتوس احلالة الكلي يف األمساك األصغر حجما من كال اجلنسني. وكان معامل متوسط احلالة الكلي للذكور واإلناث متساو إحصائيا .(p>0.05) وكان مؤشر النضج اجلنسى ادلتوسط )GSI( لدى اإلناث أعلى بكثري من الذكور )Nemipterus furcosus( ِ )GSI يف كل الشهور. كان مؤشر النضج اجلنسى ادلتوسط إلناث أبرميس ذو زعانف َسليكية وُزلََّززة ( أعلى يف شهر يونيو بينما الذكور يف شهر نوفمرب. وارتفع مؤشر النضج اجلنسى من اإلناث ارتفاعا سريعا بعد شهر ديسمرب و وصل إىل ذروهتا يف شهر يونيو ومن مث يرتاجع بعد شهر يونيو. وكذلك أ ظهرت ادلتابعة النسيجية من الغدد التناسلية أيضا مراحلمماثلة من النضج يف الذكور واإلناث. ِ )Nemipterus furcosus( وأظهرت أبرميس ذو زعانف َسليكية وُزلََّززة مرحلة الغدد التناسلية غري ناضجة يف شهري أكتوبر ونوفمرب. بعد ذلك، تدخل مرحلة النضج يف شهور ديسمرب ويناير وفرباير وتنضج يف مارس. بعد مرحلة النضج، متر اخلصى وادلبايض ألبرميس ذو زعانف ِ )Nemipterus furcosus( َسليكية وُزلََّززة مرحلة ناضجة وتفعيلها يف شهور أبريل ومايو ويونيو ويوليو. مث، متضى الغدد التناسلية يف شهر أغسطس، وأخريا تدخل مرحلة الراحة يف شهر سبتمرب. كان موسم وضع البيض ألبرميس ذو زعانف يف ادلياه الساحلية بوالية باهانغ من شهر يناير إىل أغسطس. وأشارت الدراسة النسيجية إىل أن موسم الذروة لوضع البيض يقع من شهر أبريل إىل يوليو. وأخريا يفيد هذا البحث بأن ِ الدراسة النسيجية مفيدة جدا إلدراك فرتة ذروة ل ع وضالبيض لألمساك. وستكون نتائج هذا البحث تساعد يف تربية أبرميس ذو زعانف َسليكية )Nemipterus furcosus( وُزلََّززة من أجل احلفاظ على االستغالل ادلستدام يف ادلياه الساحلية بوالية باهانغ.

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APPROVAL PAGE

I certify that I have supervised and read this study and that in my opinion, it conforms to acceptable standards of scholarly presentation and is fully adequate, in scope and quality, as a thesis for the degree of Master of Science (Bioscience)

……………..…………………… Mohammad Mustafizur Rahman Supervisor

……………..…………………… Shahbuddin Saad Co-Supervisor

……………..…………………… Ahmed Jalal Khan Chowdhury Co-Supervisor

I certify that I have read this study and that in my opinion it conforms to acceptable standards of scholarly presentation and is fully adequate, in scope and quality, as a thesis for the degree of Master of Science (Bioscience)

……………..…………………… Kamaruzzaman Yunus Examiner

……………..…………………… Mazlan Abdul Ghaffar External Examiner

This thesis was submitted to the Department of Biotechnology and is accepted as a partial fulfillment of the requirements for the degree of Master of Science (Bioscience)

……………..…………………… Noor Faizul Hadry Nordin Head, Department of Biotechnology

This thesis was submitted to the Kulliyyah of Science and is accepted as a partial fulfillment of the requirements for the degree of Master of Science (Bioscience)

……………..…………………… Kamaruzzaman Yunus Dean, Kulliyyah of Science

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DECLARATION

I hereby declare that this thesis is the result of my own investigation, except where otherwise stated. I also declare that it has not been previously or concurrently submitted as a whole for any other degrees at IIUM or other institutions.

Amira Farzana Binti Samat

Signature…………………. Date …......

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INTERNATIONAL ISLAMIC UNIVERSITY MALAYSIA

DECLARATION OF COPYRIGHT AND AFFIRMATION OF FAIR USE OF UNPUBLISHED RESEARCH

Copyright ©2014 by International Islamic University Malaysia. All rights reserved.

GROWTH AND SPAWNING OF NEMIPTERUS FURCOSUS IN THE COASTAL WATER OF PAHANG, MALAYSIA

No part of this unpublished research may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording or otherwise without prior written permission of the copyright holder except as provided below.

1. Any material contained in or derived from this unpublished research may be used by others in their writing with due acknowledgement.

2. IIUM or its library will have the right to make and transmit copies (print or electronic) for institutional and academic purposes.

3. The IIUM library will have the right to make, store in a retrieval system and supply copies of this unpublished research if requested by other universities and research libraries.

Affirmed by Amira Farzana Binti Samat

……..……..…………… ………………….. Signature Date

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ACKNOWLEDGEMENTS

In the name of Allah, the Most Gracious and the Most Merciful.

Alhamdulillah, praise to Him for giving me strength, patience, and sanity to complete this project. There are several people whom I wish to express my heartfelt feeling of gratification. Their guidance and unfaltering patience in teaching and guiding deserve utmost admiration.

First of all, I would like to thank my supervisor, Dr. Mohammad Mustafizur Rahman, and co-supervisors, Prof. Dr. Ahmed Jalal Khan Chowdhury and Dr. Shahbudin Saad for their kind consideration for bestowing me with their knowledge. Their supervision, advices and guidance from the very beginning of data collection to information regarding thesis, has given me a great opportunity to amass and gain knowledge. Working under their supervisions has given me an extraordinary exposure and experience throughout the course of this project. Their scientific intuition has made them a constant oasis of ideas in science which exceptionally inspires and enriches my development as a master student.

I would also like to thank my family, especially my father, Samat Bin Abu Bakar, my mother, Azalia Binti Ibrahim, and my sisters and brother, Afiqa, Amalina, Amzar and Ainin. Without their prayers and support, this whole ventures would have been rather pointless. I would also like to acknowledge my dear friends who have been there for me through thick and thin. My deepest gratitude to dearest Mohamad Hafiz, Nor Hafizah, Siti Aminah, Hassan, Hendy Putra, Nur Hanisah, Nor Shuhadah, Siti Nasihin, Nur Syazwani and everyone else who have supported and encouraged me to reach the end of this project and thesis writing. Your underlying love and support have been a great importance as they are the biggest source of inspiration to me.

It also a matter of great pleasure to thank and admire the staffs of Kuliyyah of Science and Kuliyyah of Medicine, namely Sr. Izyan, Br. Azmer, Br. Yahya, Br. Azizul, Br. Hanif, Sr. Zuraini, Dr. Rajkumar and other very qualified lab assistants who have helped me in the completion of my lab works. Their involvement in ensuring necessary information and protocols followed by the provision of materials that were needed contributed greatly in the completion of the project.

Thank you all.

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TABLE OF CONTENTS

Abstract ...... ii Abstract in Arabic ...... iii Approval Page ...... iv Declaration ...... v Copyright Page ...... vi Acknowledgements ...... vii List of Tables ...... x List of Figures ...... xii List of Equations ...... xv List of Symbols / Abbreviations ...... xvi

CHAPTER ONE: INTRODUCTION ...... 1 1.1 Fisheries in Malaysia ...... 1 1.2 Status of fork-tail threadfin bream in Malaysia ...... 2 1.3 growth pattern of fork-tail threadfin bream ...... 3 1.4 Condition Factor ...... 4 1.5 Spawning ...... 5 1.5.1 Gonadosomatic Index ...... 5 1.5.2 Histological Study of Gonads ...... 6 1.6 Hypothesis ...... 7 1.7 Objectives ...... 7

CHAPTER TWO: LITERATURE REVIEW ...... 8 2.1 Fork-tail threadfin bream ...... 8 2.1.1 and Species Identification ...... 8 2.2 Growth coefficient ...... 11 2.3 Condition Factor ...... 15 2.4 Spawning ...... 19 2.4.1 Gonadosomatic Index ...... 20 2.4.2 Histological Observation of Gonads ...... 21 2.4.2.1 Maturity Stages ...... 22

CHAPTER THREE: METHODOLOGY ...... 27 3.1 Area of capture ...... 27 3.2 Fish collection ...... 28 3.3 Sample measurements ...... 30 3.4 Calculations ...... 33 3.4.1 Growth Coefficient ...... 33 3.4.2 Condition Factor ...... 34 3.4.3 Gonadosomatic Index (GSI) ...... 34 3.4.4 Statistical Analysis ...... 34 3.5 Histological study of male and female gonads ...... 35 3.5.1 Chemicals ...... 35 3.5.2 Fish Dissection ...... 36 3.5.3 Tissue Fixation ...... 36

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3.5.4 Tissue Processing ...... 36 3.5.5 Embedding ...... 38 3.5.6 Sectioning ...... 40 3.5.7 Slide Mounting ...... 40 3.5.8 Haematoxylin and Eosin Staining ...... 42 3.6 Flow chart of overall methodology...... 45

CHAPTER FOUR: RESULTS AND FINDINGS ...... 47 4.1 Sex ratio ...... 47 4.2 Temporal Growth ...... 50 4.3 Temporal condition factor ...... 59 4.4 Gonadosomatic index ...... 62 4.5 Histological observation of gonads ...... 65 4.5.1 Female Gonads of N. furcosus ...... 65 4.5.1.1 Immature ...... 65 4.5.1.2 Maturing/Developing ...... 66 4.5.1.3 Mature/Spawning Capable ...... 67 4.5.1.4 Ripe and Running/Actively Spawning ...... 67 4.5.1.5 Spent/Regressing ...... 68 4.5.1.6 Resting/Regenerating ...... 69 4.5.2 Male Gonads of N. furcosus ...... 70 4.5.2.1 Immature ...... 70 4.5.2.2 Maturing/Developing ...... 70 4.5.2.3 Mature/Spawning Capable ...... 71 4.5.2.4 Ripe and Running/Actively Spawning ...... 72 4.5.2.5 Spent/Regressing ...... 73 4.5.2.6 Resting/Regenerating ...... 74 4.6 Macroscopic observation of gonads ...... 74

CHAPTER FIVE: DISCUSSION ...... 77 5.1 Sex ratio ...... 77 5.2 Growth ...... 79 5.3 Condition factor ...... 81 5.4 Gonadosomatic index ...... 82 5.5 Gonadal development ...... 83

CHAPTER SIX: CONCLUSION AND FUTURE WORK ...... 89

REFERENCES ...... 91

APPENDIX 1: ONE SAMPLE T TEST FOR GROWTH (B VALUE) ...... 100 APPENDIX 2: ANCOVA FOR COMPARED GROWTH (B VALUE) ...... 106

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LIST OF TABLES

Table No. Page No.

2.1‎ Reported a and b value for various fish species in different localities 13

2.2‎ Reported condition factor (K) of different in different locations 18

2.3‎ Standards adopted by Department of Primary Industries, State of Victoria, Australia (Charles and Alan, 2003) 19

2.4‎ Macroscopic maturity stages of male Walleye Pollock 22

2.5‎ Macroscopic maturity stages of female Walleye Pollock 23

2.6‎ Microscopic maturity stages of female Auchenoglanis occidentalis 24

2.7‎ Microscopic maturity stages of male Auchenoglanis occidentalis 24

2.8‎ Improved and simplified terminology for reproductive classification in male fishes 25

2.9‎ Improved and simplified terminology for reproductive classification in female fishes 26

3.1‎ Process of gonad tissue processing in the tissue processor (Leica TP 1020) 38

3.2‎ Details of Heamatoxylin and Eosin staining process 42

4.1‎ Monthly sex ratio of N. furcosus collected from Pahang coastal water 48

4.2‎ Monthly growth coefficient and coefficient of determinations of male and female N. furcosus from August 2012 to July 2013 51

4.3‎ Monthly comparison of growth coefficient between male and female N. furcosus from August 2012 to July 2013 52

4.4‎ Monthly relationship between total length (TL) and fork length (FL) of N. furcosus from August 2012 to July 2013 54

4.5‎ Monthly relationship between total length (TL) and standard length (SL) of N. furcosus from August 2012 to July 2013 55

4.6‎ Effects of sampling month and sex, and their effect on condition factor of male and female N. furcosus based on two-way ANOVA 60

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4.7‎ Descriptive gonadosomatic index statistics of male and female N. furcosus 62

4.8‎ Macroscopic maturity stages of female N. furcosus 75

4.9‎ Macroscopic maturity stages of male N. furcosus 76

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LIST OF FIGURES

Figure No. Page No.

2.1‎ Morphological characteristic of Nemipterus furcosus (Russell, 1990) 9

2.2‎ Distribution of N. furcosus in the world (Froese and Pauly, 2011) 10

3.1‎ Map showing area of capture of Nemipterus furcosus at the South China Sea. A indicates the LKIM Complex while B is the area of capture. 27

3.2‎ Lembaga Kemajuan Ikan Malaysia (LKIM) 28

3.3‎ Fishing vessels, which catch Nemipterus furcosus using trawl nets 29

3.4‎ Trawl nets in a fishing vessel 29

3.5‎ Measuring standard length (SL), fork length (FL) and total length (TL) using the measuring board 31

3.6‎ Measuring the fish weight using electronic weighing balance 31

3.7‎ Dissecting of fish to collect the gonads 32

3.8‎ Gonads of female (a) and male (b) N. furcosus 33

3.9‎ Male and female gonads preserved in 10% buffered formalin 36

3.10‎ Leica TP 1020 tissue processor 37

3.11‎ Leica EG 1160 embedding machine 39

3.12‎ Gonads tissue in paraffin wax block 39

3.13‎ Leica RM2245 microtome and sample embedded in paraffin wax block 40

3.14‎ Leica HI 1210 water bath (a) and Leica HI 1220 hot plate (b) for slide mounting and drying respectively 41

3.15‎ Series of Heamatoxylin and Eosin stains 43

3.16‎ Gonads observed using the Nikon Eclipse 80i microscope digital camera 44

4.1‎ Frequency distribution for total length (cm) of female (a) and male (b) N. furcosus. 49

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4.2‎ Frequency distribution for combined total length (cm) of both male and female N. furcosus. 49

4.3‎ Relationship between total length and body weight in (a) August 2012, (b) September 2012, (c) October 2012, (d) November 2012, (e) December 2012, (f) January 2013, (g) February 2013, (h) March 2013, (i) April 2013, (j) May 2013, (k) June 2013 and (l) July 2013 of female N. furcosus. 57

4.4‎ Relationship between total length and body weight in (a) August 2012, (b) September 2012, (c) October 2012, (d) November 2012, (e) December 2012, (f) January 2013, (g) February 2013, (h) March 2013, (i) April 2013, (j) May 2013, (k) June 2013 and (l) July 2013 of male N. furcosus. 59

4.5‎ Temporal changes of condition factor (mean + 95% confidence intervals) of male N. furcosus. Mean with no letter in common differ significantly (p<0.05). 60

4.6‎ Temporal changes of condition factor (mean + 95% confidence intervals) of female N. furcosus. Mean with no letter in common differ significantly (p<0.05). 61

4.7‎ Mean condition factor (Km) per length class (total length) for male and female N. furcosus. 61

4.8‎ Monthly changes of gonadosomatic index (GSI) of male and female N. furcosus. 63

4.9‎ Mean (±95% confidence intervals) GSI of male and female N. furcosus caught from the Kuantan coastal water. 63

4.10‎ Monthly percent frequency of three GSI categories (high: more than 2, medium: 1.1-2.0 and low: 0-1) of female N. furcosus. 64

4.11‎ Monthly percent frequency of three GSI categories (high: more than 0.4, medium: 2.1-4.0 and low: 0-2.1) of male N. furcosus. 64

4.12‎ Ovaries of N. furcosus at immature stage of maturation - O: Oogonia; PO: Primary oocyte; PVO: Primary vitellogenic oocyte; SVO: Secondary vitellogenic oocyte; PsVO: Post vitellogenic oocyte and ES: Empty spaces. 65

4.13‎ Ovaries of N. furcosus at maturing stage of maturation - O: Oogonia; PO: Primary oocyte; PVO: Primary vitellogenic oocyte; SVO: Secondary vitellogenic oocyte; PsVO: Post vitellogenic oocyte; OW: Ovarian wall and ES: Empty spaces. 66

4.14‎ Ovaries of N. furcosus at mature stage of maturation - O: Oogonia; PO: Primary oocyte; PVO: Primary vitellogenic oocyte; SVO:

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Secondary vitellogenic oocyte; PsVO: Post vitellogenic oocyte; OW: Ovarian wall and ES: Empty spaces. 67

4.15‎ Ovaries of N. furcosus at ripe and running stage of maturation - O: Oogonia; PO: Primary oocyte; PVO: Primary vitellogenic oocyte; SVO: Secondary vitellogenic oocyte; PsVO: Post vitellogenic oocyte; OW: Ovarian wall and ES: Empty spaces. 68

4.16‎ Ovaries of N. furcosus at spent stage of maturation - O: Oogonia; PO: Primary oocyte; PVO: Primary vitellogenic oocyte; SVO: Secondary vitellogenic oocyte; PsVO: Post vitellogenic oocyte; OW: Ovarian wall and ES: Empty spaces. 69

4.17‎ Ovaries of N. furcosus at resting of maturation - O: Oogonia; PO: Primary oocyte; PVO: Primary vitellogenic oocyte; SVO: Secondary vitellogenic oocyte; PsVO: Post vitellogenic oocyte; OW: Ovarian wall and ES: Empty spaces. 69

4.18‎ Testes of N. furcosus at immature stage of maturation - S: Spermatogonia; SC: Spermatocytes; SD: Sperm duct; ST: Spermatids; SZ: Spermatozoa and EL: Empty lumen. 70

4.19‎ Testes of N. furcosus at maturing stage of maturation - S: Spermatogonia; SC: Spermatocytes; SD: Sperm duct; ST: Spermatids; SZ: Spermatozoa and EL: Empty lumen. 71

4.20‎ Testes of N. furcosus at mature stage of maturation - S: Spermatogonia; SC: Spermatocytes; SD: Sperm duct; ST: Spermatids; SZ: Spermatozoa and EL: Empty lumen. 72

4.21‎ Testes of N. furcosus at ripe and running stage of maturation - S: Spermatogonia; SC: Spermatocytes; SD: Sperm duct; ST: Spermatids; SZ: Spermatozoa and EL: Empty lumen. 73

4.22‎ Testes of N. furcosus at spent stage of maturation - S: Spermatogonia; SC: Spermatocytes; SD: Sperm duct; ST: Spermatids; SZ: Spermatozoa and EL: Empty lumen. 73

4.23‎ Testes of N. furcosus at resting stage of maturation - S: Spermatogonia; SC: Spermatocytes; SD: Sperm duct; ST: Spermatids; SZ: Spermatozoa and EL: Empty lumen. 74

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LIST OF EQUATIONS

Equations No. Page No.

Equation 3.1 Length-weight relationship of fish 33

Equation 3.2 Linear regression on the natural logarithms 33

Equation 3.3 Fulton‟s condition factor (K) 34

Equation 3.4 Calculations of the gonadosomatic index (GSI) 34

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LIST OF SYMBOLS / ABBREVIATIONS

°C Degree Celsius % Percentage m Meters ml Milliliters cm Centimeters kg Kilogram g Grams mg Milligram K Condition factor Km Mean condition factor a Constant (intercept at y-axis) b Regression coefficient r2 Coefficient of determination χ2 Chi square p Probability ® Registered trademark ™ Trademark n Numbers EEZ Exclusive Economic Zone ASIH American Society of Ichthyologists and Herpetologists AFS American Fisheries Society MT Metric Tonne GDP Gross Domestic Production RM Ringgit Malaysia LKIM Lembaga Kemajuan Ikan Malaysia GSI Gonadosomatic Index EMR Egg Mass Ratio SL Standard Length FL Fork Length TL Total Length BW Body Weight GW Gonad Weight Log Logarithm ANOVA Analysis of Variance ANCOVA Analysis of Covariance FAO Food and Agricultural Organization HCl Hydrochloric acid

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CHAPTER ONE

INTRODUCTION

1.1 FISHERIES IN MALAYSIA

Malaysia is surrounded by marine water. It has territorial sea of 12 nautical miles and the Exclusive Economic Zone (EEZ) of about 475,600 km2 (Earth Trend, 2004), which is 1.5 times larger than its total land area. With 4,675 km coastline many coastal communities depend directly or indirectly on marine fisheries (Earth Trend,

2004). Therefore, this sector is of fundamental importance in Malaysia in many ways.

Among them revenue generation, employment and food security of coastal communities are most important. In 2009, the total production of Malaysian marine fisheries was nearly 2 million MT and it valued approximately 9000 million

Malaysian Ringgit, which contributed to 1.3% of the Malaysian gross domestic production (GDP). This sector provides approximately 150 thousand jobs directly or indirectly (Department of Fisheries, 2009). Apart from revenue generation and employment opportunity, fisheries sector supplies fish to the Malaysian peoples for consumption.

In Malaysia, the relative importance of fish is much higher than the world average. As a highly accessible food source, fish are widely consumed by Malaysian with the per capita consumption rising from 53 kg in 2002 to 56 kg in 2010 (Food and

Agricultural Organization [FAO], 2012a). This is much higher than World‟s average per capita consumption (17 kg) (FAO, 2012a). Presently, about 60% to 70% of total protein for Malaysian peoples is supplied by marine fisheries, while in

Indonesia, Japan and United States, the contribution of fish in supplying animal protein are 40%, 50% and 8%, respectively. To meet up the demand of fish for

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growing population, many counties in the World have over exploited fisheries resources. Therefore, the fisheries production has been showing poor capture production in many countries since the last decade (FAO, 2012a). In 2000, the global capture production was about 950 million MT and in 2010 the capture production was decreased nearly 900 million MT. Capture fisheries production is very important component and playing major role in the total fish production in Malaysia. In 2010, capture fisheries production contributed more than 70% of the total fish production

(FAO, 2012a).

However, fisheries production of Malaysia does meet up its domestic demand.

To meet up the domestic demand, Malaysia has been importing seafood and seafood products for a long time. In 2009, Malaysia imported seafood and seafood products

684 thousand tons, which was 26 thousand tons more than export quantity (657 thousand tons) (FAO, 2012b). As Malaysia has the huge water and fisheries resources, it can play has tremendous role in foreign exchange earnings after meeting up domestic demand of seafood and seafood products. However, proper management of fishery resources is very important for ensuring the long-term sustainability of supplying fish for Malaysian people.

1.2 STATUS OF FORK-TAIL THREADFIN BREAM IN MALAYSIA

Nemipterus furcosus, commonly known as fork-tail threadfin bream (locally known as

Kerisi) is an economically important food fish in Malaysia (Department of Fisheries,

2009). Traditionally, Malaysian people prefer this fish due to its soft and delicately flavoured flesh. Therefore, it is one of the most important target marine fish for

Malaysian fisherman. However, total production of fork-tail threadfin bream from

Malaysian water is decreasing day by day (FAO, 2012a) and this puts an increasing

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demand on the study and management of fork-tail threadfin bream population. A few studies have been conducted on the population of other economically important fish in

Malaysia but the study on the fork-tail threadfin bream population in the Malaysian water is still lacking. Adequate information about population parameters is prerequisite for the management of any wild fish stock (Rahman & Hafzath, 2012).

According to Rajkumar, Antony, & Trilles (2006), understanding basic information of any wild population particularly their growth, condition factor, gonadal development and spawning seasons are prerequisite before identifying proper management techniques on any wild fish stock. Therefore, this study aims to provide some very important basic information on growth, condition factor gonadal development and spawning seasons of fork-tail threadfin bream population in the coastal water water of Pahang.

1.3 GROWTH PATTERN OF FORK-TAIL THREADFIN BREAM

Understanding growth pattern is important in fisheries science for both applied and basic use to (i) provide information on stocks or organism condition, (ii) calculate production and biomass of a population, (iii) compare the growth and life history of fishes of different localities; (iv) determine the relative growth of small fish compared to large fish; and (v) set yield equations for estimating number of fish landed and compare the population spatio-temporally (Rahman & Hafzath, 2012; Gopalakrishnan,

Rajkumar, Rahman, Sun, Antony, Ventimaran & Trilles, 2013). Growth of wild fish is generally estimated using regression analysis of length and weight data where length is considered as an independent variable, which is the function of weight.

Therefore it is also use to (i) estimate weight from length observations because direct weight measurements can be time consuming in the field (Martin-Smith, 1996;

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Sinovcic, Franicevic, Zorica & Cikes-Kec, 2004; Gopalakrishnan et al., 2013).

Besides these, estimated growth allow conversion of length-growth equations to weight-growth equivalents in yield-per-recruit and related models.

Although growth pattern is dependent on season and size are readily available for many fishes (e.g. Koutrakis & Tsikliras, 2003; Mendes, Fonseca & Campos, 2004;

Filiz & Bilge, 2004; Oscoz, Campos & Escala, 2005; Leunda, Oscos & Miranda,

2006; Miranda, Oscoz, Leunda & Escala, 2006), adequate local information is still scarce for most fish species especially for N. furcosus (Ecoutin, Albaret & Trape,

2005).

1.4 CONDITION FACTOR

Condition factor is another important quantitative parameter that indicates the state of the fish (fatness, maturity and spawning gonadal development and general well-being of the fish) and determine present and future population success by influencing growth, reproduction and survival (Wooton, 1990; Kreiner, Van Der Lingen & Freon,

2011). However, condition factor cannot provide detail information about gonadal development of any species as it may also be greatly affected by fatness of fish.

Condition factor is a measurement that utilizes growth (length-weight) parameters of an individual fish to evaluate its well-being. According to Bagenal and

Tesch (1978), heavier fishes of certain length are in better physiological condition compared to lighter and smaller fishes. In addition, the feeding intensity, age and growth rates can also be monitored through condition factor. Since food availability is affected by the environment, the condition factor can also serve as an index to assess the status of the aquatic system in the fish habitat (Anene, 2005).

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1.5 SPAWNING

Accurate information of maturity and spawning season of fish can be obtained by histological study on gonadal development along with condition factor.

Unfortunately, there is no published information about temporal variation in maturity and gonadal development of N. furcosus in the coastal water of Pahang. However, maturity and gonadal development of fish can be understood well by studying gonadosomatic index and histological study of gonads.

1.5.1 Gonadosomatic Index

The gonadosomatic index (GSI) serves as the indicator of reproductive activity of the fish. It also helps to indentify the spawning season of fish. To determine spawning season, means GSI values are compared over different month of year by plotting mean

GSI value over time. Sudden rise of GSI values are indicative of spawning activity.

The highest GSI value, where it as at the peak level indicates the peak spawning season (Rahman & Hafzath, 2012).

However, GSI values sometimes provide incorrect information regarding the spawning season of fish. Therefore, histological study is very useful to confirm the spawning season. The spawning of fish is also influenced by factors such as day length, temperature, the availability of food, geographical location and time of the year (Castro & Huber, 2013). Nonetheless, published information on GSI and spawning of wild fork-tail threadfin bream population is lacking especially in the coastal water of Pahang, Malaysia.

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1.5.2 Histological Study of Gonads

Histological study is very important in fisheries to determine the fish reproductive cycle. Although macroscopic evaluation of fish gonads can provide particular information regarding the fish maturity stages, the ability to examine reproductive tissue at the microscopic level is very important to understand the details of fish reproduction. Principally, histological study of ovary and testes are used for better understanding of size and age at maturity, seasonal pattern of gonadal development and spawning (Fish and Wildlife Research Institute, 2014).

Presently, the classification scheme and terminology used for histology to evaluate reproductive condition of fishes have been improved. Previously, gonadal maturity stages are often referred to by number. Unfortunately, these numbers signify different classes depending on the classification system being used. Thus, a new conceptual model of the reproductive cycle has been developed that can be applied to all fish species. The model was developed by Brown-Peterson, Lowerre-Barbieri,

Macewicz, Saborido-Rey, Tomkiewicz & Wyanski (2007) at the American Society of

Ichthyologists and Herpetologists (ASIH) and American Fisheries Society (AFS) 2007 national conventions.

Understanding fish population characteristics in particular their temporal growth, condition, gonadosomatic index, gonadal development and spawning seasons are prerequisite before identifying proper management techniques on any wild fish stock. Unfortunately such information about N. furcosus is lacking, especially in the coastal water of Pahang.

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1.6 HYPOTHESIS

The growth, condition factor and gonadal development of Nemipterus furcosus in the coastal water of Pahang might be different in the different time of the year.

1.7 OBJECTIVES

1. To understand the population growth of Nemipterus furcosus in the coastal

water of Pahang.

2. To determine the population condition factor of Nemipterus furcosus

bream in the coastal water of Pahang.

3. To determine the gonadosomatic index and to identify the spawning

season of Nemipterus furcosus in the coastal water of Kuantan, Pahang.

4. To study temporal gonadal histology to confirm the spawning season of

Nemipterus furcosus in the coastal water of Pahang.

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CHAPTER TWO

LITERATURE REVIEW

2.1 FORK-TAIL THREADFIN BREAM

2.1.1 Taxonomy and Species Identification

Nemipterus furcosus, commonly known as fork-tail threadfin bream (locally known as

„Kerisi‟) is a commercially important fish in Malaysia. It is also known as Rosy threadfin bream in Australia, Peron‟s butterfly bream in Papua New Guinea and

Lagao in Philippines. This species was first described by Valenciennes in 1830

(Froese & Pauly, 2011). This species belongs to the family of Nemipteridae, which comprises of 67 species (Froese & Pauly, 2011). Female N. furcosus predominate at small size classes while male N. furcosus dominate the larger size classes. The taxonomic classification and description of N. furcosus is given below (FAOa, 2012).

Taxonomic classification:

Kingdom: Animalia

Phylum: Chordata

Subphylum: Vertebrata

Class: Actinoptergygii

Subclass: Neopterygii

Order: Aulopiformes

Suborder: Percoidei

Family: Nemipteridae

Genus: Nemipterus

Species: N. furcosus

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