Study on some biological characteristics of slugfish Sillago sihama Forsskal, 1775 in Tran De district - Soc Trang - 1

STUDENT GUIDE

MSc. PHAM THI MY XUAN KHAU BICH NHU STUDENT ID: 1153040051 CLASS: University of Science and Technology K6

Can Tho, 2015

CONFIRMATION OF GUIDE OFFICER

Thesis: Study on some biological characteristics of the slugfish Sillago sihama

(Forsskal, 1775) in Tran De district - Soc Trang. Student: Khau Bich Nhu

Student ID 1153040051

Class: Aquaculture K6

The thesis is carried out in accordance with the requirements of the supervisor.

Can Tho, date month year 2015

Staff guide students to perform

MSc. PHAM THI MY XUAN KHAU BICH NHU

COMMITMENT

I hereby certify that this thesis has been completed based on my own research results and that these research results have not been used for any other thesis of the same level.

Can Tho, date ….. month ….. year 2015 Student implementation

DEPRECIATION LIKE

ACKNOWLEDGEMENTS

To complete this research topic "Some biological characteristics of sillago sihama (Forsskal, 1775) in Tran De district - Soc Trang", I have received help from many people. I would like to sincerely thank:

The Board of Directors of Tay Do University. Especially the teachers of the Applied Biology Department who have wholeheartedly taught and imparted knowledge to us during our study at the school.

Ms. Pham Thi My Xuan, thesis supervisor. I would like to sincerely thank her for her enthusiastic guidance and valuable advice during the time of implementing the topic.

I also thank my friends in Aquaculture class 6 for helping me during the process of doing the topic.

I would like to thank my relatives who are always by my side when I encounter difficulties, encourage and support me, help me in life as well as during my studies.

Thank you very much!

Khau Bich Nhu

SUMMARY

The slugfish Sillago sihama (Forsskal, 1775) belongs to the family Sillaginidae, order fercifomes, a valuable benthic fish species in coastal areas. The slugfish samples used for the study were collected periodically every month from December 2014 to June 2015 in Tran De district - Soc Trang. Then they were kept cold and transferred to the laboratory of the Faculty of Applied Biology - Tay Do University for analysis.

The analysis results of 551 octopus samples with length from 9.5cm - 25cm corresponding to weight from 5.71g - 149g showed that the fish has a slightly flattened body, small pointed mouth, quite large fins, with 2 dorsal fins: the first dorsal fin has 9 - 11 soft rays, the second dorsal fin has 1 hard spine and 19 - 21 soft rays. On the first gill arch, the octopus has 8 - 14 gill rakers.

The mouth of the octopus has a retractable lower border, small and smooth teeth, short esophagus, sac-shaped stomach, short, folded intestine with many folds on the inner surface (RLG correlation index = 0.46 ± 0.09). The structure of the digestive system is suitable for omnivorous fish with a tendency towards animals.

The main food components of sardines include crustaceans, fish, and worms. Of which crustaceans account for the highest proportion of 27.45%, worms 23.31%, and fish 21.26%.

The research results showed that the male to female ratio of mullet was 1: 1.04, the average absolute fecundity was 19,659 ± 7887 eggs/fish and the average relative fecundity was 324.

± 113 eggs/g female fish.

Based on the results of the study on fatness and the results of the study on the sexual maturity coefficient of sardines of both sexes, we can predict that the main spawning season of sardines is in April, May, June (the beginning of the rainy season every year).

Keywords: Sillago sihama, nutrition, Reproduction, Soc Trang, Tran De.

INDEX

COMMITMENT PAGE i

ACKNOWLEDGEMENTS ii

SUMMARY iii

TABLE OF CONTENTS iv

LIST OF TABLES vii

LIST OF FIGURES viii

LIST OF ABBREVIATIONS ix

CHAPTER 1INTRODUCTION 1

1.1 Introduction 1

1.2 Objective 2

1.3 Research content 2

CHAPTER 2 LITERATURE REVIEW 3

2.1 Classification and morphological characteristics of Sillago sihama 3

2.1.1 Classification position 3

2.1.2 Morphology of Sillago sihama 4

2.2 Distribution 5

2.3 Biological characteristics of 5-ear fish

2.3.1 Growth characteristics 5

2.3.2 Nutritional characteristics 6

2.3.3 Reproductive characteristics 7

2.4 Overview of Soc Trang 8

2.4.1 Geographical location and natural conditions of Soc Trang province 8

2.5 Aquatic resources of Soc Trang province 10

2.6 Overview of research subjects. 10

CHAPTER 3 RESEARCH MATERIALS AND METHODS 12

3.1 Time and place of research 12

3.2. Research materials 12

3.2.1 Specimen 12

3.2.2 Tools and chemicals 12

3.3 Research methods 13

3.3.1 Sample collection and fixation method 13

3.3.2 Sample analysis method 13

3.4 Data processing method 18

CHAPTER 4 RESULTS AND DISCUSSION 19

4.1 Morphological characteristics of the slugfish Sillago sihama 19

4.1.1 Body shape of the sillago sihama 19

4.1.2 Length and mass relationship 21

4.2 Analysis of nutritional characteristics of mullet Sillago sihama 22

4.2.1 Anatomical morphology of the digestive tract of the slugfish Sillago sihama 22

4.2.2 Correlation between RLG and fish body length 25

4.2.3 Correlation index of intestinal length and body length 26

4.2.4 Food spectrum of sillago sihama 27

4.3 Analysis of reproductive characteristics of sillago sihama 29

4.3.1 Characteristics of gonads of the slugfish Sillago sihama 29

4.3.2 Sexual maturity stage of Sillago sihama 31

4.3.3 Variation in male to female ratio 33

4.3.4 Determination of fat content of Sillago sihama 34

4.3.5 Sexual maturity coefficient 34

4.3.6 Relative fertility and absolute fertility 36

CHAPTER 5CONCLUSION 39

5.1 Conclusion 39

5.2 Proposal 39

REFERENCES 40

APPENDIX ................................................................................................................................A

LIST OF TABLES

Table 2.1: Sexual maturity ladder according to Nikolsky (1963). 9

Table 4.1: Morphological parameters of Sillago sihama (n = 551) 20

Table 4.2: RLG index of Sillago sihama (n = 187) 26

Table 4.3: Food composition in the digestive tract of Sillago sihama mullet in Tran De district - Soc Trang according to the volumetric method... 28

Table 4.4: Food spectrum of Sillago sihama distributed in Tran De district - Soc Trang 28

Table 4.5: Showing the sex ratio of the mullet Sillago sihama 33

Table 4.6: Reproductive performance of Sillago sihama 36

Table 4.7: Correlation between length and absolute fecundity of sillago sihama

................................................................................................................................... 37