CAN THO UNIVERSITY COLLEGE OF AQUACULTURE AND FISHERIES EFFECTS OF STEROID ON ARTIFICAL PROPAGATION OF STRIPED CATFISH (Pangasianodon hypophthalmus) By NGUYEN MINH LINL A thesis submitted in partial fulfillment of the requirements for the degree of Bachelor of Aquaculture Can Tho, December 2012 CAN THO UNIVERSITY COLLEGE OF AQUACULTURE AND FISHERIES EFFECTS OF STEROID ON ARTIFICAL PROPAGATION OF STRIPED CATFISH (Pangasianodon hypophthalmus) By NGUYEN MINH LINL A thesis submitted in partial fulfillment of the requirements for the degree of Bachelor of Aquaculture Supervisors Dr BUI MINH TAM Dr PHAM THANH LIEM Can Tho, December 2012 Acknowledgements I wish to express my deep appreciation and sincere gratitude to Dr Bui Minh Tam and Dr Pham Thanh Liem for their guidance, assistance and advice have been a great help in my thesis I am thankful to the support from the staff and students in the hatchery of College of Aquaculture and Fishery, Can Tho University Especially, I would like to thank Mr Nguyen Hong Quyet Thang for his contributions in solving technical problems Moreover, I would like thank the staffs of Hung Vuong Ba Tri Company for their kind supports during my study Finally, I wish to thank my parents for their support and encouragement throughout my study i Abstract Striped catfish (Pangasianodon hypophthalmus) – known more universally by the Vietnamese name 'Tra' is an economically important species of fresh water fish in the Mekong Delta in Vietnam, which constitutes an important food resource Artificial propagation technology for Tra catfish has been recently developed along the main branches of the Mekong River where more than 60% of the local human population participate in fishing or aquaculture Extensive support for catfish culture in general and that of Tra (Pangasianodon hypophthalmus) in particular, has been provided by the Vietnamese government to increase both the scale of production and to develop international export markets The objective of my study is to find out the effects of steroid (17,20P) on artificial propagation of striped catfish (Pangasianodon hypophthalmus) The result showed that the application of HCG 1500UI/kg of female in the preliminary dose and of 17,20P at levels of 5-6 mg/kg of females in the decisive dose gave the ovulation rate of 28% Also, the use of preliminary dose by pituitary gland at mg/kg of females and the decisive dose by 17,20P at levels of 5-6 mg/kg of female gave the ovulation rate of 51% and hatching rate of 31% Using HCG 1200UI/kg in the preliminary dose and combination of 500UI HCG and 3, 4, mg/kg of 17,20P in decisive dose gave the ovulation rate 20%, 40%, 15% and hatching rate 63%, 74%, 58%, respectively Thus, the application of 17,20P in striped catfish breeding would be convenience for fish breeding farmers that they can avoid the storage of protein or peptide hormones in restricted conditions (low temperature) such as gonadotropin and gonadotropin releasing hormones ii Table of Contents Acknowledgement i Abstract ii Table of contents iii List of table iv List of figures v List of abbreviations vi Chapter I: Introduction 1.1 Background of the study 1.2 Objective of the study 1.3 contents of study Chapter II: Literature review 2.1 Biological characteristics of striped catfish 2.1.1 Morphology and distribution 2.1.2 Reproduction 2.1.2.1 Hormone control oocyte maturation 2.1.2.2 Development of Oocytes 2.1.2.3 Final oocyte maturation and ovulation 2.2 Maturation inducing steroid 17,20P (17α, 20β-dihydroxy-4-pregne-3-ones) Chapter III: Methodology 11 3.1 Time and lace 11 3.2 Materials 11 3.3 Experimental study 12 3.3.1 Experiment 12 3.3.2 Experiment 12 3.4 Broodstocks selection 13 3.5 Removal of eggs and milt, fertilization 13 3.6 Data analysis 15 3.7 Method of collecting and analyzing data 15 Chapter IV: Results and discussion 17 4.1 The experiment 1: Stimulate striped catfish spawning using HCG and pituitary gland in the priming dose and 17,20P (17α, 20β-dihydroxy-4-pregne-3ones) in the decisive dose 17 4.2 The experiment 2: stimulate catfish spawning using HCG in the priming dose and combination between HCG and 17,20P (17α, 20β-dihydroxy-4-pregne-3ones) in the decisive dose 20 4.3 The effectiveness comparison of using 17,20P and Ovaprim, HCG in artificial propagation 22 4.4 Embryonic development 22 Chapter IV: Conclusion and recommendation 25 5.1 Conclusions 25 5.2 Recommendation 25 References 26 Appendices 29 iii List of tables Table 3.1: Stimulating striped catfish spawning by using HCG or PG in priming dose and 17,20P in decisive dose 12 Table 3.2: The use preliminary dose by HCG and decisive dose by combination of HCG and 17,20P 12 Table 4.1: The result of experiment at hatchery of College of Aquaculture and Fishery 16 Table 4.2: The result of experiment at the Hung Vuong Ba Tri Company 17 Table 4.3: The result of experiment at hatchery of College of Aquaculture and Fishery 19 Table 4.3: Process of embryonic development 23 iv List of Figures Figure 2.1 Striped catfish (Pangasianodon hypophthalmus) Figure 2.2 Diagram of hormone control oocyte maturation Figure 4.1 Embryos development of striped catfish 24 v List of abbreviations HCG PG 17,20P LP RF Human Chorionic Gonadotropin Pituitary gland 17α, 20β-dihydroxy-4-pregne-3-ones latency period relative fecundity vi CHAPTER I INTRODUCTION 1.1 Background of the study Aquaculture of striped catfish, Pangasianodon hypophthalamus (Sauvage, 1878), in the Mekong Delta of Vietnam, is considered as one of the fastest growing sectors of the food production It achieved a production level of 1.195 million tons in 2011, the average yield is about 400 tones/ha/crop and over 90% of the product is processed and exported to more than 130 countries In 2011, sector generated about 1.8 billion US$ of export income The catfish farming in the Mekong Delta also provides a significant employment in the area (http://www.fistenet.gov.vn, 2012) Strong development of farming has a very high demand of artificial seeds Beside pituitary gland and HCG, scientists have found several active ingredients to stimulate the production of reproductive fish, such as sGnRHa (LHRH, Ovaprim) Currently, most of hatcheries often use types of active ingredients to stimulate the production They are pituitary gland, HCG, LHRH + Domperidon and Ovaprim These compounds are derived proteins which are instable quality and expensive, difficult to manage (decomposed at high temperature and infection), high price and instability of quality Most of these hormones make the broodstock secrete all gonadotrophic Therefore, broodstock becomes exhausted and need a long time to recover Using steroid hormone can limit these problems because of some advantages as following:  The steroid hormones can stimulate fish spawn earlier  The steroid hormone is not decomposed by bacteria and at high temperature The excess use of drugs can be preserved and saved The research on "Effects of steroid on artificial propagation of striped catfish (Pangasianodon hypophthalmus)" was conducting contribute to aquaculture development Particularly, it plays an important role in creating of artificial seed sources and rearing fish species that have high economic values 1.2 Objective of the study The overall objective is to find out effects of steroid on artificial propagation of striped catfish (Pangasianodon hypophthalmus) 1.3 Contents of the study  To stimulate catfish spawning using pituitary gland (4mg/kg) or HCG (1500UI/kg) in the priming dose and 17,20P at different dosages (5, mg/kg of females) in the decisive dose  To stimulate striped catfish spawning by using HCG in the preliminary dose and combination of 500UI/kg HCG and 3, 4, mg/kg of 17,20P in the decisive dose CHAPTER IV RESULTS AND DISCUSSIONS 4.1 The experiment 1: Stimulate striped catfish spawning using HCG and pituitary gland in the priming dose and 17,20P (17α, 20βdihydroxy-4-pregne-3-ones) in decisive dose Table 4.1: The result of stimulate striped catfish spawning using HCG and pituitary gland in the priming dose and 17,20P (17α, 20β-dihydroxy-4-pregne-3ones) in decisive dose at hatchery of College of Aquaculture and Fishery Control (HCG) HCG+ 17,20P 1500UI/kg +5mg/kg 1500UI/kg +5mg/kg 1500UI/kg +6mg/kg 1500UI/kg +6mg /kg PG + 17,20P 4mg/kg +5mg/kg 4mg/kg +5mg/kg 4mg/kg +6mg/kg 4mg/kg +6mg/kg P Fertilization RF (kg) (eggs/kg) rate (%) 3.3 62 253,500 24 336,000 3.6 75 237,000 Hatching rate (%) 45 27 81 Ovulation rate (%) 100% 50% 2.4 3.8 3.8 3.5 99,750 62,340 28 0 0 2.4 2.8 3.8 RF: relative fencudity PG: pituitary gland The result of the experiment showed that fish control had high ovulation rate (100%) However, the fertilization rate and hatching rate were slightly low with (54%) and (51%), respectively The treatment with 1500UI/kg of HCG in priming dose and 6mg of 17,20P/kg in decisive dose in this experiment displayed the 50% rate of ovulation, which is lower than control Beside, the fertilization rate was 28% but hatching rate was extremely low (0%) Latency period ranged 9-12 hours longer than control 8-10 hours Whereas, there was 0% rate of 17 ovulation in treatment PG + 17,20P This result is similar with the study of Tran Cong Bang (2009), about stimulating striped catfish spawning by using 17,20P in the decisive dose At 5mg of 17,20P /kg got 33% of ovulation and the latency extremely long ranged 14-16 hours The first experiment had been done again at the Hung Vuong Ba Tri Company The result of this experiment was showed in table 4.2 Table 4.2: The result of experiment at the Hung Vuong Ba Tri Company Control (HCG) HCG + 17,20P 1500UI/kg +5mg/kg 1500UI/kg +5mg/kg 1500UI/kg +6mg/kg 1500UI/kg +6mg /kg PG + 17,20P 4mg/kg +5mg/kg 4mg/kg +5mg/kg 4mg/kg +6mg/kg 4mg/kg +6mg/kg P RF Fertilization (kg) (eggs/kg) rate (%) 5.4 798,000 76 5.3 893,000 89 5.3 817,000 89 Hatching rate (%) 88 95 77 6.1 6.5 5.6 Ovulation rate % 100% 25% 4.9 5.8 4.6 247,000 51 30 RF: relative fencudity PG: pituitary gland The result of this experiment showed that the control got the good results with ovulation rate (100%), fertilization rate (85%), and hatching rate (87%) In high contrast, the broodstocks of the treatment of using HCG +17,20P were not ovulated The rates of ovulation, fertilization and hatching were slightly low with (25%), (51%) and (30%) respectively Latency period of treatment of using PG + 17,20P was 10 hours 18 In Viet Nam, the study of Nguyen Thi Yen Linh et al., (2011) on artificial propagation on common carp (Cyprinus caprio) show that when using 5mg of pituitary gland /kg in the preliminary dose and 3-4mg of 17,20P /kg in the decisive dose, that result displayed the high rate of ovulation (86,67%) quoted by Pham Quoc Hung & Nguyen Tuong Anh, (2011) Similarly, the study of Nguyen Tuong Anh et al., (2004) about stimulating Pangasius conchophilus by using 1500UI of HCG/kg in priming dose and 5mg of 17,20P/kg in decisive does indicated that ovulation rate (100%), fertilization rate (70-90%) and hatching rate (65-70%) Comparing with the results of those above, the present results were slightly low because of some following reason:  Prolonged low temperatures and high fluctuation of temperature between day and night  Amount of drug can be lost because of mistake in handling  Collection of broodstocks is not good and broodstocks can be stressed by handling 4.2 The experiment 2: Stimulate striped catfish spawning using HCG in the priming dose and combination between HCG and 17,20P (17α, 20β-dihydroxy-4-pregne-3-ones) in decisive dose From the result of experiment 1, the experiment had been done at hatchery of College of Aquaculture and Fishery The result of this experiment was showed in table 4.2 19 Table 4.2: The result of stimulate striped catfish spawning using HCG in the priming dose and combination between HCG and 17,20P (17α, 20βdihydroxy-4-pregne-3-ones) in decisive dose at hatchery of College of Aquaculture and Fishery P RF Fertilization (kg) (eggs/kg) rate (%) Control (HCG) Hatching rate (%) Ovulation rate (%) 3 3.6 409,500 337,500 465,000 72 65 75 23 81 85 100% HCG + (HCG +17,20P) 1200UI/kg + (500UI/kg+ 4mg/kg) 2.7 277,500 172,500 20 63 100% 1200UI/kg + (500UI/kg+ 4mg/kg) 3.8 1.7 187,500 254,420 10 40 42 74 100% 1200UI/kg + (500UI/kg+ 4mg/kg) 3.1 1.8 262,500 112,500 15 58 100% RF: relative fencudity In this experiment, the ovulation rates of broodstocks in all treatments were extremely high with 100% However, the fertilization and hatching rate in treatments were not high with 25% and 65% Among treatments, the treatment displayed high efficiency with range 10-40% of fertilization rate and 42-74% of hatching rate For the latency period, the treatments showed longer latency period (12-22 hours) than control (9-12 hours) Another study on striped catfish (Pangasianodon hypophthalmus) of Nguyen Tuong Anh et al., (2004) indicated that the use of 800UI of HCG/kg in priming dose and combination between 0,6mg of pituitary gland/kg and 17,20P in decisive dose got good result with 87±6 % of fertilization rate and 93±3 of hatching rate In other experiment, they use 800UI of HCG/kg in preliminary dose and combination between 500UI of HCG/kg and 5mg of 1720P/kg in the decisive dose gave the result with ovulation rate 100%, fertilization rate 74±17 20 and hatching rate 89±7 The finding of the present study was found to be slightly lower than other studies described above The low rate of fertilization in the experiment due to some following reasons: - Dose of the drug could be lost during processing by handling - The broodstocks in the treatment may not be well-taken care; the quality of feed for broodstock was not good Besides, the quality of ovary also depends on spawning seasons of fish: fish in the middle spawning season would show higher fertilization rates as well as hatching rate comparing to fish in the early and late season According to Pham Van Khanh (2004), the spawning season of stripped catfish is from May to September However, this study was carried out in the early of September- the late of spawning season, therefore, the quality ovary of broodstocks for treatment were not low; that also lead to the low fecundity - Broodstocks were ovulated right after they were injected with decisive dose therefore the checking of fish ovulation could be incorrect The study showed that 17,20P had effect on artificial propagation of striped catfish (Pangasianodon hypophthalmus) 17,20P cannot display its effectiveness a single way, it needs to be combined with other gonadotrophic like pituitary gland, HCG or Domperidon to stimulate the release of gonadotrophic endogenous or exogenous 21 4.3 The effectiveness comparisons of using 17,20P, HCG in artificial propagation of striped catfish Generally, 17,20P are less effective than HCG and Ovaprim about reproduction indicators (latency period, relative fecundity, fertilization rate, hatching rate …) Latency period This study showed that the latency of 17,20P was extremely high ranged 8-22 hours when comparing with the HCG in control 9-12 hours Relative fecundity From the results of this study, 17,20P and HCG had affected to stimulate striped catfish spawning The result of the experiment showed that 100% fish ovulated However, the relative fecundity when using 17,20P (112,500-277,500) was lower than HCG in control (337,500-465,000) Fertilization rate and hatching rate The fertilization rate and hatching rate when using 17,20P was slightly low (10%- 51%), (30%-74%) respectively comparing with the control using HCG (62%-89%), (45%- 95%) 4.4 Embryonic development The incubating temperature was 29-30oC, it was feverous range for embryo development and hatching Fish cannot survive in the temperature was higher than 40oC or lower than 10oC If the temperature lowers than 28oC the hatching time would be prolonged up to hours, the hatching rate would be low, the heteromorphy rate would be high and if the temperature lowers 24oC, embryos would be died (Nguyen Chung ,2007) Therefore, the temperature was optimum range for growth and development of embryos 22 Table 4.3: Process of embryonic development Figure Time Temperature Embryo shape a minute 300C Fertilized egg b After 10 minutes 300C Cleavage c After 35 minutes 300C Two-celled d After 40 minutes 300C Four- celled e After 43 minutes 300C Eight- celled f After 48 minutes 300C Sixteen- celled g After 53 minutes 300C Thirty two- celled h After 1h and 10 minutes 290C Morula i After 3h and 35 minutes 290C Blastula j After 5h and minutes 290C Gastrulation k After 11h and 55 minutes 290C Embryo indicated l After 16h and minutes 290C Embryonic movement m After 19h and 25 minutes 290C Hatching fish 23 a b d e g j c f h k i l Figure 4.1 Embryos development of striped catfish m 24 CHAPTER V CONCLUSIONS AND RECOMMENDATIONS 5.1 Conclusions 17,20P (17α, 20β-dihydroxy-4-pregne-3-ones) has affect to stimulate spawning of striped catfish (Pangasianodon hypophthalmus) The use HCG in preliminary and combination between HCG and 17,20P in decisive dose get good result In the decisive dose, 17,20P had effect on artificial propagation of striped catfish (Pangasianodon hypophthalmus) 17,20P cannot display its effectiveness a single way, it needs to be combined with other gonadotrophic like pituitary gland, HCG or Domperidon to stimulate the release of gonadotrophic endogenous or exogenous 5.2 Recommendations The application of HCG in priming dose and combination between HCG and 17,20P in the decisive dose got good results From these results, the research need to more experiments with other hormones like pituitary gland, Domperidon, combined with 17,20P in the decisive dose to find out better results 25 References Ha Phuoc Hung (2009) Broodstock management and genetic diversity of hatchery and wild stocks of striped catfish, Pangasianodon hypophthalmus (Sauvage, 1878) in Vietnam PhD Thesis, Kasetsart University 106P Huynh Van Gon (2011) Effects of Ovaprim on artificial propagation of striped catfish (Pangasianodon hypophthalmus) MSc thesis, College of Aquaculture and fishery, Can Tho university 80P (In Vietnamese) F Brian Davy and Amy Chouinard (1981) Induced fish breeding in Southeast Asia: report of workshop held in Singapore (1981) 48P Niall R Bromage and Ronald J Roberts (1995) Broodstock management and egg and larval quality Institute of aquaculture 423P Phạm Minh Thành and Nguyễn Văn Kiểm (2009) The basic of science and technology in artificial propagation Agricultural Publishing 215P (In Vietnamese) Nguyễn Chung (2007) Reproduction and culture technical of Tra catfish Agricultural Publishing, 142P (In Vietnamese) Nguyễn Dương Dũng, Nguyễn Tường Anh (2003) Stimulating common carp (Cyprinus carpio) by using 17α-hydroxy-20β- dihydroprogesteron after priming dose by LHRH-A Cited from artificial propagation of fish, steroid hormone application, Phạm Quốc Hùng & Nguyễn Tường Anh, 2011 Agricultural Publishing, Ho Chi Minh City, 214P (In Vietnamese) Nguyễn Tường Anh, Phan Văn Kỳ (2004) Using 17α, 20β-dihydroxy-4-pregne3-ones to stimulate Silver Carp (Barbodes gonionotus) and Red-tail Tinfoil Barb (Barbonymus altus) spawning Cited from artificial propagation of fish, steroid hormone application, Phạm Quốc Hùng & Nguyễn Tường Anh (2011) Agricultural Publishing, Ho Chi Minh City, 214P (In Vietnamese) 26 Nguyễn Tường Anh, Trần Chí Học,Trịnh Quốc Trọng (2000) The effect of DOCA, 17,20P and LHRH-A on gold catfish (Clarias macrocephalus): compare the effectiveness caused ripe, ovulation and other reproductive indicators Cited from artificial propagation of fish, steroid hormone application, Phạm Quốc Hùng & Nguyễn Tường Anh, (2011) Agricultural Publishing, Ho Chi Minh City, 214P (In Vietnamese) Nguyễn Tường Anh (2005) Production techniques of some fish species Agricultural Publishing, Ho Chi Minh City, 238P (In Vietnamese) Nguyễn Tường Anh, Nguyễn Thị Ngọc Duyên, Nguyễn Hà Thanh Phong (2005) Stimulate striped cathfish (Pangasianodon hypophthalmus) and sutchi catfish (Pangasius conchophilus) spawning by using 17α, 20β-dihydroxy4-pregne-3-ones in decisive dose Cited from artificial propagation of fish, steroid hormone application, Phạm Quốc Hùng & Nguyễn Tường Anh (2011) Agricultural Publishing, Ho Chi Minh City, 214P (In Vietnamese) Lê Văn Dân, Nguyễn Tường Anh, Võ Văn Phú (2007) Stimulating grass carp (Ctenopharyngodon idellus) spawn by using 17α, 20β-dihydroxy-4pregne-3-ones (17,20P) in decisive dose Cited from artificial propagation of fish, steroid hormone application, Phạm Quốc Hùng & Nguyễn Tường Anh (2011) Agricultural Publishing, Ho Chi Minh City, 214P (In Vietnamese) Trần Minh Đức (2010) Reproductive indicators comparisons and striped catfish (Pangasianodon hypophhalmus) nursing from different broodstock sources Graduate theis College of Aquaculture and Fishery, Can Tho University 39P (In Vietnamese) Trần Công Bằng (2009) The effect of 17,20P (17α, 20β-dihydroxy-4-pregne-3ones) on artificial propagation of stripped catfish (Pangasianodon hypophthalmus) Graduate theis College of Aquaculture and Fishery, Can Tho University 39P (In Vietnamese) Import and export (2012) Fish exports reached $ 1.6 billion Retrieved from: 27 http://www.fistenet.gov.vn/f-thuong-mai-thuy-san/a-xuat-nhap-khau/nam2011-xuat-khau-ca-tra-uoc-111at-1-6-ty-usd 28 Appendices Appendices 1: The result of experiment at hatchery of College of Aquaculture and Fishery Control (HCG) HCG + 17,20P PG + 17,20P P (kg) time time Priming Decisive P of egg 3.3 500 UI/kg 500 UI/kg 500 UI/kg 500 UI/kg 1500 UI/kg 1500 UI/kg 3500 UI/kg 3500 UI/kg 169g 244g 3.6 500 UI/kg 500 UI/kg 1500 UI/kg 3500 UI/kg 2.4 3.8 3.8 3.5 0 0 0 0 1500 UI/kg 1500 UI/kg 1500 UI/kg 1500 UI/kg 5mg/kg 5mg/kg 6mg/kg 6mg/kg 2.4 2.8 3.8 0 0 0 0 4mg/kg 4mg/kg 4mg/kg 4mg/kg 5mg/kg 5mg/kg 6mg/kg 6mg/kg st nd LP: lantency period RF: relative fencudity 29 LP RF 253500 336000 158g 8h30 hours 10 hours 243g 161g hours 12hours 99750 62340 237000 Appendices 2: The result of experiment at hatchery of Hung Vuong Ba Tri Company Control (HCG) HCG + 17,20P PG + 17,20P P (kg) 1st time 2nd time Priming Decisive P of egg LP RF 5.4 5.3 5.3 500 UI/kg 500 UI/kg 500 UI/kg 500 UI/kg 500 UI/kg 500 UI/kg 1500 UI/kg 1500 UI/kg 1500 UI/kg 3500 UI/kg 3500 UI/kg 3500 UI/kg 420g 470g 430g hours 9h20 9h30 798000 893000 817000 6.1 6.5 5.6 0 0 0 0 1500 UI/kg 1500 UI/kg 1500 UI/kg 1500 UI/kg 5mg/kg 5mg/kg 6mg/kg 6mg/kg 130g 10 hours 247000 4.9 5.8 4.6 0 0 0 0 4mg/kg 4mg/kg 4mg/kg 4mg/kg 5mg/kg 5mg/kg 6mg/kg 6mg/kg LP: lantency period RF: relative fencudity 30 Appendices 3: The result of experiment at hatchery of College of Aquaculture and Fishery P (kg) 1st time 2nd time Priming 3 3.6 500 UI/kg 500 UI/kg 500 UI/kg 500 UI/kg 500 UI/kg 500 UI/kg 2.7 0 3.8 1.7 3.1 1.8 Control (HCG) HCG + 17,20P Decisive P of egg LP RF 1500 UI/kg 1500 UI/kg 1500 UI/kg 3500 UI/kg 3500 UI/kg 3500 UI/kg 273 225 310 hours 7h20 8h30 409500 337500 465000 0 1200 UI/kg 1200 UI/kg 500 UI/kg + 3mg 500 UI/kg + 3mg 185g 115g 22 hours 15h30 277500 172500 0 0 1200 UI/kg 1200 UI/kg 500 UI/kg + 4mg 500 UI/kg + 4mg 125g 185g 12 hours 18h 45 187500 254420 0 0 1200 UI/kg 1200 UI/kg 500 UI/kg + 5mg 500 UI/kg + 5mg 175g 75g 18h35 19 hours 262500 112500 LP: lantency period RF: relative fencudity 31 [...]... study on striped catfish (Pangasianodon hypophthalmus) of Nguyen Tuong Anh et al., (2004) indicated that the use of 800UI of HCG/kg in priming dose and combination between 0,6mg of pituitary gland/kg and 17,20P in decisive dose got good result with 87±6 % of fertilization rate and 93±3 of hatching rate In other experiment, they use 800UI of HCG/kg in preliminary dose and combination between 500UI of HCG/kg... Gastrulation k After 11h and 55 minutes 290C Embryo indicated l After 16h and 5 minutes 290C Embryonic movement m After 19h and 25 minutes 290C Hatching fish 23 a b d e g j c f h k i l Figure 4.1 Embryos development of striped catfish m 24 CHAPTER V CONCLUSIONS AND RECOMMENDATIONS 5.1 Conclusions 17,20P (17α, 20β-dihydroxy-4-pregne-3-ones) has affect to stimulate spawning of striped catfish (Pangasianodon hypophthalmus). .. Dopamine antagonic (Doperidone, Pimozide) PITUITARY Ovaprim GTH II- maturational Ganadotropin  FOLLICLES GONADOTROPHIC (Pituitary gland, HCG, PMS) C21 Steroid (17,20)P  MPF OOCYTES STEROID (17,20P; 17P; DOC; Progesteron) Figure 2.2 Diagram of hormones stimulating maturation and ovulation of oocyte (Nguyen Tuong Anh, 2006) 6 2.1.2.2 Development of Oocytes The identities of pituitary hormones that regulate... striped catfish, Pangasianodon hypophthalmus (Sauvage, 1878) in Vietnam PhD Thesis, Kasetsart University 106P Huynh Van Gon (2011) Effects of Ovaprim on artificial propagation of striped catfish (Pangasianodon hypophthalmus) MSc thesis, College of Aquaculture and fishery, Can Tho university 80P (In Vietnamese) F Brian Davy and Amy Chouinard (1981) Induced fish breeding in Southeast Asia: report of workshop... characteristics of striped catfish 2.1.1 Morphology and distribution Morphological classification of striped catfish is as follows: Kingdom Animalia Phylum Chordata Subphylum Vertebrata Class Osteichthyes Order Siluriformes Family Pangasiidae Genus Pangasianodon Species Pangasianodon hypophthalmus (Sauvage, 1878) Figure 2.1: Striped catfish Pangasianodon hypophthalmus ( Pham Van Khanh, 1996) Striped catfish, ... combination between HCG and 17,20P in decisive dose get good result In the decisive dose, 17,20P had effect on artificial propagation of striped catfish (Pangasianodon hypophthalmus) 17,20P cannot display its effectiveness a single way, it needs to be combined with other gonadotrophic like pituitary gland, HCG or Domperidon to stimulate the release of gonadotrophic endogenous or exogenous 5.2 Recommendations... early of September- the late of spawning season, therefore, the quality ovary of broodstocks for treatment were not low; that also lead to the low fecundity - Broodstocks were ovulated right after they were injected with decisive dose therefore the checking of fish ovulation could be incorrect The study showed that 17,20P had effect on artificial propagation of striped catfish (Pangasianodon hypophthalmus). .. Butskaya, 1978) In which stages III, IV and the transition from phase IV to V, the growth of oocytes is controlled by pituitary hormone and follicle cells are receiving the stimulation of hormones to produce steroid hormones that control corresponding create yolk and ovulation (Nguyen Tuong Anh, 1999) 5 The ecological factors (Rain, temperature, pheromone) The Senses BRAIN  Hypothalamus  Feedback Antiestrogen... possible involvement of other hormones has not been examined Treatment of sea trout with oestradiol induces production of vitellogenin and also the hepatic oestrogen receptor, an intermediary in the oestrogen regulation of vitellogensis (Copeland and Thomas 1988; Smith and Thomas 1990) The 2 month period of oocyte growth in sea trout coincides with seasonal increases in plasma concentrations of the oestrogen... combined with other gonadotrophic like pituitary gland, HCG or Domperidon to stimulate the release of gonadotrophic endogenous or exogenous 21 4.3 The effectiveness comparisons of using 17,20P, HCG in artificial propagation of striped catfish Generally, 17,20P are less effective than HCG and Ovaprim about reproduction indicators (latency period, relative fecundity, fertilization rate, hatching rate