study on reproductive biology of vermiculated sailfin catfish (pterygoplichthus disjunctivus weber, 1991) in can tho and đong thap provinces

CAN THO UNIVERSITY COLLEGE OF AQUACULTURE AND FISHERIES STUDY ON REPRODUCTIVE BIOLOGY OF VERMICULATED SAILFIN CATFISH (Pterygoplichthus disjunctivus Weber, 1991) IN CAN THO AND ĐONG THAP PROVINCES By NGUYEN KIM CUONG A thesis submitted in partial fulfillment of the requirements for the degree of Bachelor of Aquaculture Science Can Tho, December 2013 CAN THO UNIVERSITY COLLEGE OF AQUACULTURE AND FISHERIES STUDY ON REPRODUCTIVE BIOLOGY OF VERMICULATED SAILFIN CATFISH (Pterygoplichthys disjunctivus Weber, 1991) IN CAN THO AND ĐONG THAP PROVINCES By NGUYEN KIM CUONG A thesis submitted in partial fulfillment of the requirements for the degree of Bachelor of Aquaculture Science Supervisor Assoc. Prof. Dr. TRAN DAC DINH Can Tho, December 2013 APPROVEMENT The thesis “Study on reproductive biology of vermiculated sailfin catfish (Pterygoplichthys disjunctivus Weber, 1991) in Can Tho and Dong Thap provinces” defended by Nguyen Kim Cuong, which was edited and passed by committee on 12-27-2013 Sign of Supervisor Sign of Student Assoc. Prof. Dr Tran Dac Dinh Nguyen Kim Cuong i ACKNOWLEDGEMENT My special thanks are given to Assoc. Prof. Dr. Tran Dac Dinh for his constant guidance and useful advices that helped me to conduct and complete this thesis. Thanks to the teaching staffs in department of fisheries management and economics, College of Aquaculture and Fisheries – Can Tho University and students of Advanced Aquaculture Program Class Course 2nd for enthusiasm help during the period of sampling and data analysis. Thanks to Miss. Ho Thi Thuy Huong and Nguyen Thi Vang help me during the period of experimentation and data analysis. Finally, I would like to thank to my family and friends helped and made the best conditions for me during my study of bachelor program in aquaculture. Nguyen Kim Cuong ii ABTRACT This thesis studied on reproductive biology of vermiculated sailfin catfish (Pterygoplichthys disjunctivus,Weber 1991) in Can Tho and Dong Thap provinces from July to October in 2013. The results indicated that length-weight relationships were very close with high R2, including total length-weight relationship equation W=0.0115L2.8967 with R2 = 0.9759 (n=216) and standard length-weight relationship equation W=0.0759L2.5647 with R2 = 0.9485 (n=216). Besides, condition factor (CF) of males was the highest in September (0.0119) and the lowest was in October (0.0111), CF of females was the highest in October (0.0119) and the lowest CF was in August (0.0112). Next, maturity proportion was the highest in July (90%) and the lowest was in September (69.61%),most of males were mature in July and August (more than 70% ) and the females were mature in months from July to October (more than 90%), sex proportion were 93 females (43.06% ), 123 males (56.94% ) and sex ratio ( female: male) was : 1.32. In addition, Gonadosomatic index (GSI) of males was the highest in August (0.6175%) and the lowest was in October (0.0659%), GSI of females were very high (5.5246% -8.3018%), the highest was in October (8.3018%) and the lowest was in August (5.5246%). Hepatosomatic index (HSI) of males was the highest in August (1.1195%) and the lowest was in October (0.8378%), HSI of females also was the highest in August (1.2109%) and the lowest was in October (0.8388%). Average of fecundity of Pterygoplichthyus disjuntivuswas 2002 eggs/female (324 – 6621 eggs/female), average of relative fecundity was 13 eggs/gram of female (4 – 23 eggs/gram of female). The fecundity of fish was not stable because Pterygoplichthyus disjunctivus reproduced many time per year. Fecundity – weight relationship of Pterygoplichthyus disjuntivuswas indicated by equation F = 16.203W0.9456 with R2= 0.836.Finally, total length at first maturity was indicated by equation y = -0.639x + 9.926 with R2 = 0.842, the result of total length at first maturity was 15.53 cm. iii TABLE OF CONTENT Acknowledgements . i Abstract iii TABLE OF CONTENT . iv LIST OF TABLES . vi List of figures vii LIST OF ABBREVIATIONS .viii CHAPTER I INTRODUCTION 1. Background of the research 2. Research objective 3. Research contents . CHAPTER II LITERATURE 1. Overview of natural condition, aquaculture and fisheries in Can Tho . 2.Overview of natural condition, aquaculture and fisheries in Dong Thap . 3. Classification, morphological characteristics and distribution of Pterygoplichthyus disjunctivus (Weber, 1991) . 4. Nutritional characteristics . 5. Growth characteristics 6.Reproduction characteristics . 7. Environmental impacts . 10 CHAPTER III . 12 MATERIALS AND METHODOLOGY . 12 1. Materials . 13 2. Methodology . 13 2.1 Sampling and fixing samples 13 2.2 Criteria for sample analysis 13 2.3 Length-weight relationship and condition factor (CF) . 13 2.4 Maturity stages, maturity proportion and sex ratio 14 2.5 Gonadosomatic Index (GSI) . 15 2.6 Hepatosomatic Index (HSI) 16 2.7 Fecundity . 16 iv 2.8 Total length at first maturity (Lm) 17 2.9 Data analysis method . 17 CHAPTER IV . 18 RESULTS AND DISCUSSIONS 18 1. Morphological criteria and characteristics 18 2. Length – weight relationship and condition factor (CF) 20 2.1 Total length – weight relationship 20 2.2 Standard length – weight relationship . 20 2.3 Condition factor (CF) . 22 3. Maturity stages, maturity proportion and sex ratio 23 3.1 Maturity proportion and maturity stages 23 3.2 Sex ratio 25 4. Gonadosomatic index (GSI) . 26 6. Fecundity 29 7. Total length at first maturity . 31 CHAPTER V 32 CONCLUSIONS AND RECOMMENDATIONS . 32 1.Conclusions . 32 1.1 Length-weight relationship and condition factor 32 1.2 Gonadosomatic index (GSI) 32 1.3 Hepatosomatic index (HSI) 33 1.4 Fecundity 33 1.5 Total Length at first maturity . 33 Recommendations 33 REFERENCE . 34 APPENDIX 36 v LIST OF TABLES Table 1: Description of Maturity stages (Nikolsky 1963) 15 Table 2: Comparison of morphological criteria between Pterygoplichthyus disjunctivus (Weber, 1991) with other researchs 18 Table 3:Propotion of morphological criteria of Pterygoplichthyus disjunctivus . 18 Table 4: Condition factor (CF) of Pterygoplichthyus disjunctivus (males) . 22 Table 5: Condition factor (CF) of Pterygoplichthyus disjunctivus (females) 22 Table 6: Maturity proportion (%) of Pterygoplichthyus disjunctivus 23 Table 7: Sex proportion (%) and sex ratio of Pterygoplichthyus disjunctivus in every month 26 Table 8: Gonadosomatic index of Pterygoplichthyus disjunctivus (males) 26 Table 9: Gonadosomatic index of Pterygoplichthyus disjunctivus (females) . 27 Table 10: Hepatosomatic index of Pterygoplichthyus disjunctivus (males) 28 Table 11: Hepatosomatic index of Pterygoplichthyus disjunctivus (females) . 29 Table 12: Determination of total length at first maturity of Pterygoplichthyus disjunctivus . 31 vi LIST OF FIGURES Figure 1: Vermiculated sailfin catfish (Pterygoplichthys disjunctivus Weber,1991) Figure 2: Sampling area in Can Tho . 12 Figure 3: Sampling area in Dong Thap 12 Figure 4: Vermiculated sailfin catfish (Pterygoplichthyus disjunctivus Weber, 1991) 19 Figure 5: Sucker mouth of Vermiculated sailfin catfish (Pterygoplichthyus disjunctivus Weber, 1991) 19 Figure 6: Total length – weight relationship of Pterygoplichthyus disjunctivus 20 Figure 7: Standard length–weight relationship of Pterygoplichthyus disjunctivus 21 Figure 8: Condition factor (CF) of Pterygoplichthyus disjunctivus (males) 22 Figure 9: Condition factor (CF) of Pterygoplichthyus disjunctivus (females) . 23 Figure 10: Maturity stages proportion (%) of males . 24 Figure 11: Maturity stages Proportion (%) of females . 25 Figure 12: Sex proportion of Pterygoplichthyus disjunctivus in months 25 Figure 13: Gonadosomatic index of pterygoplichthyus disjunctivus (males) . 26 Figure 14: Gonadosomatic index of Pterygoplichthyus disjunctivus (females) 27 Figure 15: Hepatosomatic index of Pterygoplichthyus disjunctivus (males) . 28 Figure 16: Hepatosomatic index of Pterygoplichthyus disjunctivus (females) 29 Figure 17: Fecundity – weight relationship of Pterygoplichthyus disjunctivus 30 Figure 18: Total lenght at first maturity of Pterygoplichthyus disjunctivus . 31 vii LIST OF ABBREVIATIONS P Pectoral fin V Ventral fin A Anal fin D Dorsal fin W Weight of fish L Length of fish TL Total length FL Fork length SL Standard length CF Condition factor GSI Gonadosomatic index HIS Hepatosomatic index F Fecundity Lm Total length at first maturity n Amount of samples G Weight of the ovaries g Weight of the sub-sample P Maturity proportion WL Weight of liver GW Gonad weight BW Body weight viii 42 21.2 71.34 2.8967 0.01026 43 18.7 79.51 2.8967 0.01645 44 24.2 121.95 2.8967 0.01196 45 19.8 60.74 2.8967 0.01065 46 22 80.09 2.8967 0.01035 47 19.3 59.39 2.8967 0.01122 48 22 89.62 2.8967 0.01158 49 21.5 76.76 2.8967 0.0106 50 22.2 77.13 2.8967 0.00971 51 20.1 59.16 2.8967 0.00993 52 22.3 90.08 2.8967 0.01119 53 23.5 100.45 2.8967 0.01072 54 20.5 68.91 2.8967 0.01093 55 21.7 88.92 2.8967 0.01196 56 29.8 235.98 2.8967 0.01266 57 42.5 532.85 2.8967 0.01022 58 24.5 140.36 2.8967 0.01328 59 13.5 22.61 2.8967 0.01202 60 15.5 34.01 2.8967 0.01212 61 14.3 26.34 2.8967 0.01186 62 13.6 18.04 2.8967 0.00939 63 10.7 11.54 2.8967 0.01203 64 10.4 11.18 2.8967 0.01266 65 12.8 19.53 2.8967 0.01212 66 11.5 14.74 2.8967 0.01247 67 15.5 30.01 2.8967 0.0107 68 14.5 22.3 2.8967 0.00964 69 14.5 25.97 2.8967 0.01123 70 11.5 17.89 2.8967 0.01514 71 8.3 6.13 2.8967 0.01334 72 10 9.06 2.8967 0.01149 73 11 12.8 2.8967 0.01232 74 14.5 28.62 2.8967 0.01237 75 14.7 29.54 2.8967 0.01228 76 13.5 26.09 2.8967 0.01388 77 16 33.06 2.8967 0.01075 78 14.2 27.18 2.8967 0.01249 79 15 37.94 2.8967 0.01487 80 26 161.21 2.8967 0.01284 81 23.5 133.56 2.8967 0.01426 82 32.5 331.74 2.8967 0.01385 83 38 460 2.8967 0.01221 84 38.2 440 2.8967 0.0115 85 45 660 2.8967 0.01073 42 86 37.6 440 2.8967 0.01204 87 36.5 371.94 2.8967 0.01109 88 26.6 157.77 2.8967 0.01176 89 20.2 77.17 2.8967 0.01277 90 28 204.73 2.8967 0.01316 91 19 78.19 2.8967 0.01545 92 24.8 108.66 2.8967 0.00993 93 34.6 324.23 2.8967 0.01129 94 21.5 71.59 2.8967 0.00989 95 30.3 236.73 2.8967 0.0121 96 18.5 61.56 2.8967 0.01314 97 31.5 227.91 2.8967 0.01041 98 23.2 117.13 2.8967 0.01298 99 28.5 168.13 2.8967 0.01027 100 25.8 129.84 2.8967 0.01058 101 37.7 393.13 2.8967 0.01067 102 28.2 171.89 2.8967 0.01082 103 23.8 114.46 2.8967 0.01178 104 22 89.85 2.8967 0.01161 105 19.6 62.99 2.8967 0.01138 106 19.6 56.2 2.8967 0.01015 107 22.8 92.29 2.8967 0.01076 108 21.9 75.72 2.8967 0.00992 109 18 47.67 2.8967 0.01102 110 20 55.91 2.8967 0.00952 111 33.4 262.05 2.8967 0.01011 112 35.3 300.31 2.8967 0.00987 113 20.1 70.31 2.8967 0.0118 114 25 108.85 2.8967 0.00971 115 19 51.56 2.8967 0.01019 116 23.2 104.36 2.8967 0.01156 117 23.2 100.59 2.8967 0.01115 118 23.6 97.25 2.8967 0.01026 119 21.2 77.54 2.8967 0.01116 120 21 69.48 2.8967 0.01028 121 26.6 157.77 2.8967 0.01176 122 20.2 77.17 2.8967 0.01277 123 28 204.73 2.8967 0.01316 43 Condition factor (CF) of females No. TL(cm) W(g) b CF 26.3 148.55 2.8967 0.01145 24.8 130.42 2.8967 0.01191 23.7 111.46 2.8967 0.01161 27.2 167.34 2.8967 0.01170 14 24.5 2.8967 0.01173 13.8 20.88 2.8967 0.01042 16 32.85 2.8967 0.01068 16.5 34.18 2.8967 0.01016 15.6 25.98 2.8967 0.00909 10 17.2 40.13 2.8967 0.01058 11 15.7 30.9 2.8967 0.01061 12 18.5 47.61 2.8967 0.01016 13 18.6 78.27 2.8967 0.01645 14 21.2 65.64 2.8967 0.00944 15 17.5 38.59 2.8967 0.00968 16 23.2 132.28 2.8967 0.01466 17 18.5 57.28 2.8967 0.01223 18 26.2 157.23 2.8967 0.01225 19 27.8 148.71 2.8967 0.00976 20 24.4 109.75 2.8967 0.01051 21 32.8 334.56 2.8967 0.01360 22 28.6 171.81 2.8967 0.01038 23 36.2 302.77 2.8967 0.00925 24 42 550 2.8967 0.01092 25 35 349.46 2.8967 0.01177 26 33.2 297.18 2.8967 0.01166 27 34 400.28 2.8967 0.01466 28 17.6 41.87 2.8967 0.01033 29 22.5 84.95 2.8967 0.01029 30 18.2 52.01 2.8967 0.01164 31 16.8 33.68 2.8967 0.00951 32 14.5 24.45 2.8967 0.01057 33 16.5 36.09 2.8967 0.01073 34 16.7 39.6 2.8967 0.01137 35 17 38.3 2.8967 0.01045 36 22.7 105.21 2.8967 0.01242 37 33.8 344.65 2.8967 0.01284 38 22.8 90.45 2.8967 0.01054 39 22.8 90.03 2.8967 0.01049 40 28 148.4 2.8967 0.00954 41 24 93.12 2.8967 0.00935 44 42 22.6 96.48 2.8967 0.01153 43 23.1 97.38 2.8967 0.01093 44 19.4 54.75 2.8967 0.01019 45 28 159.03 2.8967 0.01022 46 21.1 72.58 2.8967 0.01059 47 21 64.64 2.8967 0.00956 48 23.5 78.24 2.8967 0.00835 49 32.6 305.86 2.8967 0.01265 50 22 91.06 2.8967 0.01177 51 19 63.94 2.8967 0.01264 52 21.7 86.96 2.8967 0.01169 53 22.7 75.79 2.8967 0.00895 54 19.7 81.92 2.8967 0.01458 55 22.6 103.12 2.8967 0.01233 56 26.5 170.25 2.8967 0.01283 57 29.7 202.21 2.8967 0.01096 58 28 174.51 2.8967 0.01122 59 13.2 22.91 2.8967 0.01300 60 12.5 23.92 2.8967 0.01590 61 16.7 40.19 2.8967 0.01154 62 19.5 59.83 2.8967 0.01097 63 30 237.84 2.8967 0.01252 64 30.2 249.35 2.8967 0.01287 65 33.2 330 2.8967 0.01295 66 34.6 470 2.8967 0.01636 67 38.9 520 2.8967 0.01289 68 34.6 390.6 2.8967 0.01360 69 35.5 450 2.8967 0.01454 70 30.8 252.98 2.8967 0.01234 71 26.8 168.71 2.8967 0.01231 72 26.5 134.52 2.8967 0.01014 73 30.3 208.41 2.8967 0.01066 74 33 231.49 2.8967 0.00924 75 26.7 207.09 2.8967 0.01528 76 28.3 165.76 2.8967 0.01033 77 21 74.73 2.8967 0.01105 78 20 67.15 2.8967 0.01144 79 23.7 108.42 2.8967 0.01129 80 19.1 56.98 2.8967 0.01109 81 27.9 212.91 2.8967 0.01383 82 24 121.8 2.8967 0.01223 83 23.1 105.01 2.8967 0.01178 84 22.3 90.18 2.8967 0.01121 85 19.5 63.13 2.8967 0.01157 45 86 18.6 50.33 2.8967 0.01058 87 18 63.09 2.8967 0.01458 88 29.5 224.88 2.8967 0.01243 89 20 84.35 2.8967 0.01437 90 20.5 80.14 2.8967 0.01271 91 21 73.36 2.8967 0.01085 92 19 56.94 2.8967 0.01125 93 19.6 65.53 2.8967 0.01183 Percentage of maturity proportion of males (July-October) Month Stage 1,2 Stage Stage Stage 5% 15% 55% 0% 15.71% 8.57% 34.29% 0% 26.47% 7.72% 12.99% 0% 10 10.17% 16.95% 31.36% 0% Percentage of maturity proportion of females (July-October) Month Stage 1,2 Stage Stage Stage 0% 0% 15% 5% 0% 12.86% 28.57% 0% 3.92% 5.88% 42.04% 0.98% 10 0% 0% 36.44% 5.08% Gonadosomatic index of males No. W(g) GW(g) GSI 65.53 7.6 11.5977 50.47 6.14 12.1656 55.62 2.41 4.3330 127.75 0.32 0.2505 107.22 0.02 0.0187 245.32 0.14 0.0571 175.36 0.21 0.1198 151.37 0.13 0.0859 105.22 0.41 0.3897 10 110.84 0.2 0.1804 11 198.24 0.19 0.0958 12 186.37 0.21 0.1127 13 145.94 0.26 0.1782 46 14 165.17 0.13 0.0787 15 166.53 0.22 0.1321 16 242.26 0.22 0.0908 17 185.14 0.23 0.1242 18 211.53 0.24 0.1135 19 18.9 0.01 0.0529 20 42.83 0.02 0.0467 21 32.62 0.01 0.0307 22 54.27 0.01 0.0184 23 26.14 0.01 0.0383 24 26.16 0.01 0.0382 25 50.51 0.07 0.1386 26 160.33 0.3 0.1871 27 149.81 0.22 0.1469 28 167.22 0.22 0.1316 29 100.24 0.08 0.0798 30 68.89 0.09 0.1306 31 169.94 0.09 0.0530 32 107.87 0.13 0.1205 33 123.54 0.09 0.0729 34 168.2 0.12 0.0713 35 51.29 0.05 0.0975 36 73.31 0.09 0.1228 37 144.59 15.57 10.7684 38 206.21 0.01 0.0048 39 174.44 0.02 0.0115 40 326.87 0.11 0.0337 41 84.18 0.01 0.0119 42 35.97 0.01 0.0278 43 43.03 0.05 0.1162 44 50.93 0.01 0.0196 45 71.34 0.11 0.1542 46 79.51 0.21 0.2641 47 121.95 0.1 0.0820 48 60.74 0.12 0.1976 49 80.09 0.01 0.0125 50 59.39 0.09 0.1515 51 89.62 0.05 0.0558 52 76.76 0.09 0.1172 53 77.13 0.04 0.0519 54 59.16 0.09 0.1521 55 90.08 0.15 0.1665 56 100.45 0.07 0.0697 47 57 68.91 0.04 0.0580 58 88.92 0.04 0.0450 59 235.98 0.14 0.0593 60 532.85 0.49 0.0920 61 140.36 0.02 0.0142 62 22.61 0.01 0.0442 63 34.01 0.01 0.0294 64 26.34 0.01 0.0380 65 18.04 0.01 0.0554 66 11.54 0.01 0.0867 67 11.18 0.01 0.0894 68 19.53 0.01 0.0512 69 14.74 0.01 0.0678 70 30.01 0.01 0.0333 71 22.3 0.01 0.0448 72 25.97 0.01 0.0385 73 17.89 0.01 0.0559 74 6.13 0.01 0.1631 75 9.06 0.01 0.1104 76 12.8 0.01 0.0781 77 28.62 0.01 0.0349 78 29.54 0.01 0.0339 79 26.09 0.01 0.0383 80 33.06 0.01 0.0302 81 27.18 0.01 0.0368 82 37.94 0.01 0.0264 83 161.21 0.02 0.0124 84 133.56 0.01 0.0075 85 331.74 0.2 0.0603 86 460 0.21 0.0457 87 440 0.4 0.0909 88 660 1.17 0.1773 89 440 0.45 0.1023 90 371.94 0.63 0.1694 91 157.77 0.01 0.0063 92 77.17 0.01 0.0130 93 204.73 0.23 0.1123 94 78.19 0.01 0.0128 95 108.66 0.02 0.0184 96 324.23 0.14 0.0432 97 71.59 0.01 0.0140 98 236.73 0.09 0.0380 99 61.56 0.01 0.0162 100 227.91 0.18 0.0790 48 101 117.13 0.01 0.0085 102 168.13 0.21 0.1249 103 129.84 0.1 0.0770 104 393.13 0.4 0.1017 105 171.89 0.13 0.0756 106 114.46 0.06 0.0524 107 89.85 0.04 0.0445 108 62.99 0.02 0.0318 109 56.2 0.04 0.0712 110 92.29 0.09 0.0975 111 75.72 0.03 0.0396 112 47.67 0.03 0.0629 113 55.91 0.03 0.0537 114 262.05 0.24 0.0916 115 300.31 0.38 0.1265 116 70.31 0.1 0.1422 117 108.85 0.06 0.0551 118 51.56 0.08 0.1552 119 104.36 0.17 0.1629 120 100.59 0.06 0.0596 121 97.25 0.08 0.0823 122 77.54 0.06 0.0774 123 69.48 0.02 0.0288 Gonadosomatic index (GSI) of females No. W(g) GW (G) GSI 148.55 8.21 5.5268 130.42 6.63 5.0836 52.09 0.02 0.0384 111.46 8.61 7.7247 167.34 25.08 14.9875 24.5 0.48 1.9592 20.88 0.37 1.7720 32.85 1.71 5.2055 34.18 4.64 13.5752 10 25.98 1.04 4.0031 11 40.13 4.05 10.0922 12 30.9 3.47 11.2298 13 47.61 0.14 0.2941 14 78.27 2.5 3.1941 15 65.64 3.1 4.7227 16 38.59 0.1 0.2591 17 132.28 15.79 11.9368 49 18 57.28 1.47 2.5663 19 157.23 12.86 8.1791 20 148.71 5.77 3.8800 21 109.75 0.18 0.1640 22 334.56 43.9 13.1217 23 171.81 9.83 5.7214 24 302.77 13.36 4.4126 25 550 50.03 9.0964 26 349.46 54.46 15.5840 27 297.18 2.03 0.6831 28 400.28 31.05 7.7571 29 41.87 1.93 4.6095 30 84.95 9.83 11.5715 31 52.01 2.55 4.9029 32 33.68 3.72 11.0451 33 24.45 0.92 3.7628 34 36.09 3.64 10.0859 35 39.6 1.93 4.8737 36 38.3 1.91 4.9869 37 105.21 3.91 3.7164 38 344.65 38.51 11.1737 39 90.45 0.66 0.7297 40 90.03 9.34 10.3743 41 148.4 14.58 9.8248 42 93.12 0.16 0.1718 43 96.48 3.26 3.3789 44 97.38 3.26 3.3477 45 54.75 1.05 1.9178 46 159.03 8.25 5.1877 47 72.58 0.94 1.2951 48 64.64 6.18 9.5606 49 78.24 30.52 39.0082 50 305.86 10.23 3.3447 51 91.06 10.23 11.2344 52 63.94 5.32 8.3203 53 86.96 12.49 14.3629 54 75.79 2.65 3.4965 55 81.92 13.78 16.8213 56 103.12 9.84 9.5423 57 170.25 18.31 10.7548 58 202.21 0.07 0.0346 59 174.51 21.34 12.2285 60 22.91 0.01 0.0436 61 23.92 0.01 0.0418 50 62 40.19 0.01 0.0249 63 59.83 0.03 0.0501 64 237.84 10.4 4.3727 65 249.35 39.68 15.9134 66 330 7.34 2.2242 67 470 24.81 5.2787 68 520 20.88 4.0154 69 390.6 46.42 11.8843 70 450 11.13 2.4733 71 252.98 30.39 12.0128 72 168.71 2.14 1.2684 73 134.52 4.44 3.3006 74 208.41 20.76 9.9611 75 231.49 14.28 6.1687 76 207.09 14.57 7.0356 77 165.76 11.24 6.7809 78 74.73 9.3 12.4448 79 67.15 7.62 11.3477 80 108.42 14.97 13.8074 81 56.98 1.78 3.1239 82 212.91 5.9 2.7711 83 121.8 10.26 8.4236 84 105.01 15.22 14.4939 85 90.18 8.02 8.8933 86 63.13 2.27 3.5958 87 50.33 2.36 4.6891 88 63.09 9.91 15.7077 89 224.88 11.97 5.3228 90 84.35 10.09 11.9621 91 80.14 4.92 6.1393 92 73.36 6.46 8.8059 93 56.94 5.52 9.6944 Hepatosomatic index (HSI) of males No. TL(cm) W(g) WL (g) HS I 26.6 127.75 1.23 0.962818 22.8 107.22 1.84 1.716098 28.3 245.32 1.93 0.786728 28.4 175.36 2.05 1.169024 25.5 151.37 1.04 0.687058 23.4 105.22 0.68 0.646265 24.2 110.84 0.57 0.514255 51 30.3 198.24 2.36 1.190476 28.5 186.37 1.5 0.804851 10 26.5 145.94 0.84 0.575579 11 28.2 165.17 2.49 1.507538 12 28.8 166.53 1.72 1.032847 13 29.7 242.26 1.57 0.648064 14 17.5 52.09 0.45 0.863889 15 29.3 185.14 1.09 0.588744 16 30 211.53 0.91 0.430199 17 13.4 18.9 0.08 0.42328 18 18.3 42.83 0.45 1.050665 19 17.2 32.62 1.7 5.211527 20 19.7 54.27 0.51 0.939746 21 15.1 26.14 0.13 0.497322 22 15 26.16 0.19 0.7263 23 19.2 50.51 0.65 1.286874 24 26.6 160.33 2.45 1.528098 25 26.2 149.81 1.77 1.181497 26 28 167.22 1.18 0.705657 27 21 100.24 1.15 1.147247 28 20.7 68.89 0.38 0.551604 29 26.6 169.94 1.59 0.935624 30 24.5 107.87 1.17 1.084639 31 23 123.54 1.04 0.841833 32 23 168.2 1.01 0.600476 33 18.5 51.29 0.42 0.818873 34 22.3 73.31 0.9 1.227663 35 25 144.59 0.85 0.587869 36 28.4 206.21 2.15 1.042626 37 25.3 174.44 1.25 0.716579 38 34 326.87 3.74 1.144186 39 20.2 84.18 0.99 1.176051 40 17 35.97 0.53 1.47345 41 18 43.03 0.57 1.324657 42 18 50.93 0.16 0.314157 43 21.2 71.34 0.63 0.883095 44 18.7 79.51 0.62 0.779776 45 24.2 121.95 0.4 0.328003 46 19.8 60.74 0.58 0.95489 47 22 80.09 0.6 0.749157 48 19.3 59.39 0.75 1.262839 49 22 89.62 0.41 0.457487 50 21.5 76.76 0.33 0.429911 51 22.2 77.13 0.3 0.388954 52 52 20.1 59.16 0.09 0.15213 53 22.3 90.08 0.96 1.065719 54 23.5 100.45 0.76 0.756595 55 20.5 68.91 0.39 0.565956 56 21.7 88.92 0.36 0.404858 57 29.8 235.98 0.61 0.258496 58 42.5 532.85 2.77 0.519846 59 24.5 140.36 1.6 1.139926 60 13.5 22.61 0.21 0.928793 61 15.5 34.01 0.66 1.940606 62 14.3 26.34 0.12 0.455581 63 13.6 18.04 0.09 0.498891 64 10.7 11.54 0.09 0.779896 65 10.4 11.18 0.09 0.805009 66 12.8 19.53 0.26 1.331285 67 11.5 14.74 0.16 1.085482 68 15.5 30.01 0.26 0.866378 69 14.5 22.3 0.22 0.986547 70 14.5 25.97 0.24 0.924143 71 11.5 17.89 0.21 1.17384 72 8.3 6.13 0.01 0.163132 73 10 9.06 0.02 0.220751 74 11 12.8 0.02 0.15625 75 14.5 28.62 0.26 0.908456 76 14.7 29.54 0.34 1.150982 77 13.5 26.09 0.38 1.456497 78 16 33.06 0.38 1.149425 79 14.2 27.18 0.57 2.09713 80 15 37.94 0.1 0.263574 81 26 161.21 1.9 1.178587 82 23.5 133.56 1.24 0.928422 83 32.5 331.74 3.22 0.97064 84 38 460 5.9 1.282609 85 38.2 440 4.27 0.970455 86 45 660 4.32 0.654545 87 37.6 440 5.72 1.3 88 36.5 371.94 3.78 1.016293 89 26.6 157.77 1.33 0.842999 90 20.2 77.17 0.84 1.088506 91 28 204.73 3.17 1.548381 92 19 78.19 0.68 0.869676 93 24.8 108.66 0.73 0.67182 94 34.6 324.23 2.3 0.709373 95 21.5 71.59 0.52 0.726358 53 96 30.3 236.73 2.38 1.005365 97 18.5 61.56 0.82 1.332034 98 31.5 227.91 1.59 0.697644 99 23.2 117.13 1.38 1.178178 100 28.5 168.13 0.99 0.58883 101 25.8 129.84 1.71 1.317006 102 37.7 393.13 2.93 0.745301 103 28.2 171.89 1.67 0.971552 104 23.8 114.46 1.46 1.275555 105 22 89.85 0.71 0.790206 106 19.6 62.99 0.47 0.74615 107 19.6 56.2 0.22 0.391459 108 22.8 92.29 0.29 0.314227 109 21.9 75.72 0.21 0.277338 110 18 47.67 0.19 0.398574 111 20 55.91 0.56 1.00161 112 33.4 262.05 4.13 1.576035 113 35.3 300.31 1.44 0.479505 114 20.1 70.31 0.93 1.322714 115 25 108.85 0.79 0.725769 116 19 51.56 0.53 1.027929 117 23.2 104.36 0.58 0.555768 118 23.2 100.59 0.46 0.457302 119 23.6 97.25 0.63 0.647815 120 21.2 77.54 0.39 0.502966 121 21 69.48 0.6 0.863558 122 17.2 50.47 0.26 0.515158 123 19.2 55.62 0.43 0.773103 Hepatosomatic index (HSI) of females No. TL(cm) W(g) WL (g) HSI 26.3 148.55 1.9 1.279031 24.8 130.42 1.6 1.226806 23.7 111.46 1.05 0.942042 27.2 167.34 2.33 1.392375 14 24.5 0.18 0.734694 13.8 20.88 0.2 0.957854 16 32.85 0.68 2.070015 16.5 34.18 0.47 1.375073 15.6 25.98 0.27 1.039261 10 17.2 40.13 0.93 2.317468 11 15.7 30.9 0.41 1.326861 12 18.5 47.61 0.42 0.882168 54 13 18.6 78.27 1.02 1.303181 14 21.2 65.64 0.83 1.264473 15 17.5 38.59 0.19 0.492356 16 23.2 132.28 1.63 1.232235 17 18.5 57.28 0.83 1.449022 18 26.2 157.23 1.72 1.093939 19 27.8 148.71 0.93 0.625378 20 24.4 109.75 0.92 0.838269 21 32.8 334.56 5.86 1.751554 22 28.6 171.81 2.6 1.5133 23 36.2 302.77 4.22 1.393797 24 42 550 7.59 1.38 25 35 349.46 3.42 0.978653 26 33.2 297.18 3.71 1.248402 27 34 400.28 5.33 1.331568 28 17.6 41.87 0.67 1.600191 29 22.5 84.95 1.25 1.471454 30 18.2 52.01 0.74 1.422803 31 16.8 33.68 0.5 1.484561 32 14.5 24.45 0.53 2.167689 33 16.5 36.09 0.6 1.66251 34 16.7 39.6 0.67 1.691919 35 17 38.3 0.67 1.749347 36 22.7 105.21 0.71 0.674841 37 33.8 344.65 3.28 0.95169 38 22.8 90.45 0.88 0.972913 39 22.8 90.03 0.52 0.577585 40 28 148.4 0.65 0.438005 41 24 93.12 0.41 0.440292 42 22.6 96.48 0.5 0.518242 43 23.1 97.38 0.18 0.184843 44 19.4 54.75 0.5 0.913242 45 28 159.03 0.45 0.282965 46 21.1 72.58 0.42 0.578672 47 21 64.64 0.95 1.469678 48 23.5 78.24 0.38 0.485685 49 32.6 305.86 4.63 1.513764 50 22 91.06 0.53 0.582034 51 19 63.94 0.81 1.266813 52 21.7 86.96 0.57 0.655474 53 22.7 75.79 0.79 1.042354 54 19.7 81.92 2.59 3.161621 55 22.6 103.12 0.76 0.737005 56 26.5 170.25 1.95 1.145374 55 57 29.7 202.21 1.12 0.55388 58 28 174.51 1.36 0.779325 59 13.2 22.91 0.22 0.960279 60 12.5 23.92 0.2 0.83612 61 16.7 40.19 0.51 1.268972 62 19.5 59.83 0.48 0.802273 63 30 237.84 2.38 1.000673 64 30.2 249.35 1.73 0.693804 65 33.2 330 3.99 1.209091 66 34.6 470 5.13 1.091489 67 34.6 390.6 5.74 1.469534 68 35.5 450 7.81 1.735556 69 30.8 252.98 2.83 1.118666 70 26.8 168.71 1.72 1.019501 71 26.5 134.52 1.14 0.847458 72 30.3 208.41 3.29 1.578619 73 33 231.49 3.52 1.520584 74 26.7 207.09 3.51 1.694915 75 28.3 165.76 1.94 1.170367 76 21 74.73 0.51 0.682457 77 20 67.15 0.55 0.819062 78 23.7 108.42 0.66 0.608744 79 19.1 56.98 0.44 0.772201 80 27.9 212.91 1.48 0.695129 81 24 121.8 0.7 0.574713 82 23.1 105.01 0.7 0.666603 83 22.3 90.18 0.37 0.410291 84 19.5 63.13 0.33 0.522731 85 18.6 50.33 0.28 0.556328 86 18 63.09 0.37 0.586464 87 29.5 224.88 1.4 0.622554 88 20 84.35 0.67 0.794309 89 20.5 80.14 0.55 0.686299 90 21 73.36 0.61 0.831516 91 19 56.94 0.67 1.176677 92 19.6 65.53 0.37 0.564627 93 18.6 78.27 1.02 1.303181 56 Fecundity and relative fecundity of Pterygoplichthyus disjunctivus STT 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 Weight (g) 148.55 130.42 167.34 34.18 40.13 30.9 78.27 65.64 132.28 57.28 157.23 148.71 334.56 171.81 302.77 550 349.46 400.28 41.87 84.95 33.68 36.09 39.6 105.21 344.65 90.03 148.4 96.48 96.48 64.64 78.24 305.86 91.06 252.98 134.52 208.41 231.49 207.09 Weight of ovary (g) 8.21 6.63 25.08 4.64 4.05 3.47 2.5 3.1 15.79 1.47 12.86 5.77 43.9 9.83 13.36 50.03 54.46 31.05 1.93 9.83 3.72 3.64 1.93 3.91 38.51 9.34 14.58 3.26 8.25 6.18 30.52 10.23 10.23 30.39 4.44 20.76 14.28 14.57 Weight of Subsample (g) 1.52 1.14 1.69 0.88 0.81 0.6 0.27 0.34 1.48 0.11 0.78 0.25 1.69 0.87 0.84 2.51 1.39 1.96 0.45 1.03 0.93 0.67 0.33 0.53 1.65 1.26 1.19 0.35 0.98 0.65 1.92 1.39 1.11 1.6 0.55 1.44 0.78 0.96 Amount of eggs in Sub sample 394 267 238 101 136 56 94 105 167 98 108 105 223 231 256 156 169 224 102 82 85 75 66 188 251 168 134 131 93 123 68 169 115 143 208 192 206 162 57 Fecundity 2128.118 1552.816 3531.976 532.545 680.000 323.867 870.370 957.353 1781.709 1309.636 1780.615 2423.400 5792.722 2610.034 4071.619 3109.434 6621.396 3548.571 437.467 782.583 340.000 407.463 386.000 1386.943 5858.188 1245.333 1641.782 1220.171 782.908 1169.446 1080.917 1243.791 1059.865 2716.106 1679.127 2768.000 3771.385 2458.688 Relative fecundity 14.326 11.906 21.107 15.581 16.945 10.481 11.120 14.585 13.469 22.864 11.325 16.296 17.314 15.191 13.448 5.654 18.948 8.865 10.448 9.212 10.095 11.290 9.747 13.183 16.997 13.832 11.063 12.647 8.115 18.092 13.815 4.067 11.639 10.736 12.482 13.282 16.292 11.873 [...]... of them include alteration of bank structure and erosion, disruption of aquatic food chains, competition with native species, mortality of endangered shore birds, changes in aquatic plant communities and damage to fishing gear and industry Some provinces have high density of vermiculated sailfin catfish are Can Tho, An Giang, Dong Thap, Soc Trang, Vinh Long, Tra Vinh, specially is in Can Tho and Dong... appraisal and effective methods for management, protection and development aquatic resources So topic study on reproductive biology of the vermiculated sailfin catfish in Can Tho and Dong Thap provinces ” is very necessary 2 Research objective To find out some reproductive biological characteristics of vermiculated sailfin catfish (Pterygoplichthys disjunctives Weber 1991) distributed in Can Tho and Dong Thap. .. Tho City has 9 administrative units including 5 urban districts of Ninh Kieu, Binh Thuy, Cai Rang, O Mon, Thot Not and four suburban districts of Phong Dien, Co Do, Thoi Lai, Vinh Thanh with 5 towns, 44 wards and 36 communes (statistical data from the time of issuing the Decree 12/ND-CP) 2.Overview of natural condition in Dong Thap Dong Thap is a province in the Mekong Delta region of southern Vietnam,... and fecundity 3 CHAPTER II LITERATURE 1 Overview of natural condition in Can Tho Can Tho is directly under the Central authorities, lies in the heart of the Mekong River Delta, bordered by An Giang and Dong Thap in the north, Vinh Long in the East , Hau Giang in the South and Kien Giang in the West Being dubbed as “the capital city of the Southwestern Vietnam” more than one hundred years ago, Can Tho. .. surface of aquatic plants Abundance of Vermiculated sailfin catfish is the cause of declining some native aquatic species because it not only vies food but also eats eggs of other species, controlling is very difficult if it invades with high density Figure 1: Vermiculated sailfin catfish (Pterygoplichthys disjunctivusWeber ,1991) 1 In Viet Nam, special concern is development of vermiculated sailfin catfish. .. main wind direction, northeast wind (dry season) and southwest wind ( rain season), average wind speed was 1.8 m/s, few storms but it will be in rain season Topography: Can Tho has relatively flat terrain, average height is about 1 – 2 m, It is convenient for agriculture and fishery production Can Tho lies in the half-flooded plains that were gradually sloping from northeast to southwest, including... three kinds of terrain: natural dikes alongside Hau River (forming the strip of high land and islands along Hau River); half-flooded 4 plains (belonging to the Long Xuyen Tetragon that is directly influenced by the flood every year); delta plains (mainly influenced by the tide and some interactive influences from the crop-end floods) Hydrology: Can Tho had dense river, channel, canal system and many... length and 280-350 m, flow through O Mon, Phong Dien, Cai Rang, Ninh Kieu provinces, it has freshwater year round which help for irrigation in dry season, drainage in rain season and transportation Besides, there are many other rivers and channel such as Thot Not, Vinh Thanh, Co Do, Phong Dien that help for soil improvement, irrigation, breeding, cultivation… Administrative organization: Can Tho City... Dong Thap Controlling can be done easily in ponds for aquaculture by draining and cleaning ponds but it is very difficult to do in natural conserves Researches about species composition, biological characteristics, growth characteristics, its impacts on the ecosystem, competition with other species, its regions of residence, fertility, measures to control of vermiculated sailfin catfish need to be done... vegetation and creating mats that could shade them from sunlight 11 CHAPTER III MATERIALS AND METHODOLOGY Duration: from July to October 2013 Location: - Can Tho river, Ninh Kieu dictrict, Can Tho - Truong Xuan commune, Thap Muoi dictrict, Dong Thap province Sampling area Figure 2: Sampling area in Can Tho Sampling area Figure 3: Sampling area in Dong Thap 12 1 Materials Equipment: Bistoury, electronic scales, . index (GSI) 32 1 .3 Hepatosomatic index (HSI) 33 1.4 Fecundity 33 1.5 Total Length at first maturity 33 2 Recommendations 33 REFERENCE 34 APPENDIX 36 vi LIST OF TABLES Table. first maturity 31 CHAPTER V 32 CONCLUSIONS AND RECOMMENDATIONS 32 1.Conclusions 32 1.1 Length-weight relationship and condition factor 32 1.2 Gonadosomatic index (GSI) 32 1 .3 Hepatosomatic. impacts 10 CHAPTER III 12 MATERIALS AND METHODOLOGY 12 1. Materials 13 2. Methodology 13 2.1 Sampling and fixing samples 13 2.2 Criteria for sample analysis 13 2 .3 Length-weight relationship