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CAN THO UNIVERSITY COLLEGE OF AQUACULTURE AND FISHERIES EFFECT OF PROBIOTICS SUPLEMENT IN WATER ON GROWTH AND SURVIVAL RATE OF COBIA LARVAE (Rachycentron canadum) By DANG DIEM TUONG 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 EFFECT OF PROBIOTICS SUPLEMENT IN WATER ON GROWTH AND SURVIVAL RATE OF COBIA LARVAE (Rachycentron canadum) By DANG DIEM TUONG A thesis submitted in partial fulfillment of the requirements for The degree of Bachelor of Aquaculture Supervisor Assoc Prof Dr TRAN NGOC HAI Dr LE QUOC VIET Can Tho, December 2012 Acknowledgements First of all, I wish to give my honest thank to Rectorate Board of Can Tho University, lecturers and instructors of CAF and Auburn University who have facilitated for my studying during 4.5 years in Can Tho city By my deep gratitude I would like to give my thanks to Assoc Prof Dr Tran Ngoc Hai, Dr Le Quoc Viet and Mr Tran Nguyen Duy Khoa who instructed me enthusiastically to finish the thesis research For other valuable help and guide, thanks are extended to all my friends in brackish water hatchery, Nguyen Thanh Trung, Huynh The Hien, Pham Nguyen Duy, Dao Khanh Au, Nguyen Thi Tuyet Nhung and students of the course 35 I wish to express my sincere gratitude to my advisor, Dr Pham Minh Duc for his constant guidance, and thanks to all my beloved classmates in Advanced Aquaculture Program class for all great encouragement and kind help during 4.5 years in CAF Finally, I thank my family and all my friends who have supported and encouraged me to study and finish my course Abstract This study aimed to evaluate the effects of different dosages of probiotics supplemented in water on growth and survival rates of cobia larvae (Rachycentron canadum) A triplicated experiment was conducted with differrent treatments of probiotics including the control (without probiotics); 0.5 mg/m3, mg/m3, mg/m3.The experiment was conducted in 500-L tanks holding with 2500 fry per tank (5 larvae/L), and supplied aeration continuously Brackishwater of 30ppt was used for the experiment Rotifer enriched with DHA, vitamin C and probiotics was used to feed the larvae on day-post-hatch (dph) to 10 dph at 10inds/ mL Beginning on the 7dph, umbrella Artemia were suplemently fed to cobia larvae at 24 inds/ mL, and on the 11 dph, enriched artemia nauplii were fed to larvae to the end of the experiment In addition, Chlorella algae were also supplied into the nursing tank system every three days Feeding frequency was mantained three times/day at 6:00am, 12:00am, and 6:00pm Probiotics were applied to the experimental water every days After weeks of rearing, larvae from different treatments reach to 13.86 mm to 15.11 mm in body length There was no significant difference in length of cobia larvae among control and treatments (p>0.05) Survival rate of fry after weeks of rearing was highest (5.61 %) in treatment with mg/m3 of probiotic and lowest (3.81%) in the control which is signigicantly different from another In conclusion, probiotics help improve water quality, survival rates; reduced size variation of larvae, and relatively improved the growth of larvae It is reccommeded from this study is to apply probiotics 1g/m3 every days Further studies on the use of probiotics and needed Table of Contents Acknowledgements i Abstract ii Table of contents iii List of Tables v List of Figures vi List of Abbreviations vii CHAPTER I INTRODUCTION 10 1.1 Background of the study 1.2 Objectives of the study 1.3 Content of the study 11 10 11 CHAPTER II LITERATURE REVIEW 12 2.1 Biological features of cobia 12 2.1.1 Classification and taxonomy 12 2.1.2 Habitat and distribution 12 2.1.3 Morphology of cobia 12 2.1.4 Food and nutrition 13 2.1.5 Reproductivity 13 2.2 Overview about the status of cobia production and study in the world 14 2.2.1 Study background of cobia Error! Bookmark not defined 2.3 Probiotics using status and study 14 CHAPTER III METHODOLOGY 16 3.1 Time and location for research 3.2 Study materials 16 16 3.2.1 Equipments for study 16 3.2.2 Water source 16 3.2.3 Feed 16 3.3 Research methodology 19 3.3.1 Experiment systems 19 3.3.2 Experimental design 19 3.3.3 Feeding methods 19 3.3.4 Management and data collection 19 3.4 Statistical analysis 21 CHAPTER IV RESULTS AND DISCUSSIONS 22 4.1 Environmental factors 4.2 Growth of larvae 24 22 4.2.1 Growth in body length of fry 24 4.2.2 Growth rates 26 4.3 Variation in body length of larvae 26 4.4 Survival rates 28 CHAPTER V CONCLUSIONS AND RECOMMENDATIONS 5.1 Conclusions 30 5.2 Recommendations 30 References 31 30 Appendex 26 List of Tables Table 3.1: Biochemical composition of some zooplankton Table 3.2: Artemia composition 10 Table 3.3: Water quality monitoring methods 12 Table 4.1: Temperature and pH values in the cobia fry to juvenile experiment 15 Table 4.2: Growth rate of cobia larvae during 21 days 17 Table 4.3: Coefficience of variance of cobia larval length after 21 days of rearing 19 List of Figures Figure 4.1a: Variation of temperature during the culture period 15 Figure4.1 b: Variation of TAN concentration during culture period 16 Figure 4.1.c: Variation of Nitrite concentration during culture period 16 Figure 4.2: Growth in body length of cobia larvae from different treatments during culture period 17 Figure 4.3: Distribution in body length of cobia larvae from different treatments after 21 days of culture 20 Figure 4.4: Survival rate of cobia larvae from different treatments after 21 days of culture 21 List of Abbreviations dph Day post hatch ppt Part Per Thousand CFU/g Colony Former Unit DHA decos DLG Daily Length Gain SGR Specific Growth Rate SR Survival Rate LC50 Lethal Concentration of 50% dead of organisms CV Coefficience of Variance HUFA High unsaturated Fatty Acid PUFA Polyunsaturated Fatty Acid UV Ultraviolet Initial BLi…………………………………………………… Initial Body Length Final BLf……………………………………………………… Final Body Length CHAPTER I INTRODUCTION 1.1 Background of the study In recent years, marine culture is developing in many countries as well as in Viet Nam However, technologies of marine aquaculture species production still maintain very new activities Among many marine species, cobia (Rachycentron canadum) is considered a potential species for marine aquaculture According to Briggs (1960), Shaffer and Nakamura (1989), cobia distributes world-wide and occur in many areas of tropical and subtropical seas exclude the Eastern Pacific Like other marine species such as sea bass, salmon, grouper, cobia (Rachycentron canadum) is a popular species and being cultured in many countries in the world Similar to salmon culture industry, the cobia has a potential to become a commercially high value marine culture species Moreover, the cobia has high tolerance to unfavorable conditions and potentials to be cultured in cages in the open sea With the advantages of a long coastline (nearly 3260km), large exclusive economic zone (more than million km2) and very large area of brackish water surface area, Viet Nam has a great potiential for brackish water and marine aquaculture In recent years, marine aquaculture in Vietnam has been developing very fast and a large number of high quality juveniles is required In order to satisfy this demand, many research on seed production of sea bass (Lates calcarifer), grouper (Epinephelus spp) and Cobia (Rachycentron canadum) have been conducted to develop technology for hatchery production In the Mekong Delta, cage culture of Cobia has been developed in Kien Giang Province However, it still relies on wild seed collected from the sea In order to contribute to development of technology for Cobia seed production, this study on “Effect of probiotics supplement in water on survival and growth rate of cobia (Rachycentron canadum) larvae” was carried out 10 Figure 4.3: Graphical presentation of cobia fry’s CV after 21 days of experiment Figure 4.3: Distribution in body length of cobia larvae from different treatments after 21 days of culture 4.4 Survival rates After 21 days of experiment, survival rate (SR) of larvae from different treatments ranged from 81% to 5.61% There was significant difference (p>0,05) among the control and the treatments which the treatments with Probiotics 1g/L gave the best results (5.61%) Benetti et al., (2008) had showed the survival rate of 21dph in intensive flow through tanks with larvae/ L and 10 larvae/ L were 31.4 – 34.9% and 17.5 – 19.2%, respectively 28 In the intensive recirculating tanks the survival rates were 12.7% and 9.4% of larvae/ L and 10 larvae/ L, respectively (Hitzfelder et al., 2006) Benetti et al.(2008) applied the intensive flow through system to maintain good water quality with diet regime of rotifer and artermia enriched with high nutrients (HUFA, PUFA, AlgamacARA…) and application of UV light to treat the sea water Probiotics effects on prevention of disease have been studied for aquaculture since 1980 (Farzanfar, 2006) and have showed a promise to use the probiotics in live feed for marine fish larviculture and aquaculture in general (Carnevali et al., 2004; Rotman et al., 2005) Benetti et al., (2008) showed that consistent use of probiotics in live feeds fed to the larvae contributed to high production levels with the Survival rate of 17.5-19.2% and 31.4-34.9% of 10 larvae/L and larvae/L, respectively Survival rate (%) 7.00 4.88ab 6.00 5.00 5.61a 4.23ab b 3.81 4.00 3.00 2.00 1.00 0.00 0.5 Probiotic dosage( g/m3 ) Figure 4.4: Survival rate of cobia larvae from different treatments after 21 days of culture Values in the collume with different letters are significant difference (p< 0.05) 29 CHAPTER V CONCLUSIONS AND RECOMMENDATIONS 5.1 Conclusions Application of probiotics during larval rearing of cobia gave in promising results as it reduced Nitrite concentration, improved survival rates and reduced size variation of larvae However, probiotics improved relatively but not significanlly the growth of larvae from this study The most suitable dosage of probiotics is from 0.5-1g/m3 applying every three days due to high survival rates 5.2 Recommendations Further studies on application of different types and using methods of probiotics to cobia larval rearing is needed Further studies on nutrition and feeding of cobia larvae for better survival rate and growth are necessary 30 References Benetti, D.D., Bruno Sardenberg, Aaron Welch, Ronald Hoenig, M Refik Orhun, Ian Zink, 2008 Intensive larval husbandry and fingerling production of cobia Rachycentron canadum Aquaculture, Volume 281, Issues 1-4, September 2008, page 22-27 Boy, C E 1998 Water quanlity in ponds aquaculture Benetti, D,D., Orhun, M.R., Sardenberg, B., O’Hanlon, B., Welch, A., Hoenig, R., Zink, l.,Rivera, J.A., Denlinger, B., Bacoat, D., Palmer, K., Cavalin, F., 2008 Advances in hatchery and grow-out technology of cobia Rachycentron canadum Briggs, J.C., 1960 Fish of worldwide (circumtroical) distribution Copeia 3, 171-180 Burn, K.M., C Neidig, J Lotz and R Overstreet 1998 Cobia (Rachycentron canadum) stock asseement study in the Gulf of Mexico and in the south Atlantic Mote Mar Lab.Tech Rep 571 108pp Caylor, R.E, Patricia M Biesiot and James S Franks, 1994 Culture of cobia (Rachycentron canadum) cryopreservation of sperm and induced spawning Aquaculture Volume 125, Issues 1-2, August 1994, Pages 81-92 Chang, 2008 Cobia in idyllic Central Vietnam ,Aquaculture Asia Pacific (6) 25-26 Craig, S.R, Michael H Schwarz, Ewen McLean, 2006 Juvenile cobia (Rachycentron canadum) can unilize a wide range of protein and lipid levels without impacts on production characteristics Aquaculture 261 (2006) 384–391 Cynthia K Faulk and G Joan Holt, 2009 Biochemical composition and quality of captive-spawned cobia Rachycentron canadum eggs Aquaculture, Volume 279, Issues 14, July 2008, Pages 70-76 Carnevali, O., Zamponi, M., sulpizio, R., Nardi, M., Orpianesis, C., Silvi, S., Caggiano, M., Polzonetti, A., 2004, Administration of probiotics strain to improve sea bream wellness during development Aquac 12(4-5) 377-386 Douillet, Christopher J Langdon.,1994 Use of a probiotic for the culture of larvae of the Pacific oyster (Crassostrea gigas Thunberg) Aquaculture Volume 119, Issue 1, 25–40 31 Do Van Khuong, 2011 Study of technology of sea and brackish water seed production and culture of some high economic potential of brackish water species in Viet Nam FAO (2009), Fishbase 12/2009 FAO, 2009 Rachycentron canadum (Linnaeus, 1766) http://www.fao.org/fishery/culturedspecies/Rachycentron_canadum/en Faulk, C.K., Jeffrey B Kaiser, G Joan Holt, 2007 Growth and survival of larval and juvenile cobia Rachycentron canadum in a recirculating raceway system Aquaculture, Volume 270, Issues 1-4, 28 september 2007, page 149-157 Faulk,C.K., G Joan Holt, 2005 Advances and rearing cobia Rachycentron canadum larvae in recirculating aquaculture systems: Live prey enrichment and greenwater culture Aquaculture 249 (2005), page 231– 243 Farzanfar, A., 2006 The use of probiotics in shrimp aquaculture FEUS Immunol Med Microbiol 48 (2) 149-158 Liao, l., Su, H., Chang, E., 2001, Techniques in finfish larviculture in Taiwan Aquaculture 200, 1-31 Gomez-Gil, A Roque, J F Turnbull, 2000 The use and selection of probiotic Bacteria for Use in the Culture of Larval Aquatic Organisms Aquaculture (2000) Volume: 191, Issue: 1-3, Pages: 259-270 Gomez-Gil, A Roque, J F Turnbull, 2000 The use and selection of probiotic Bacteria for Use in the Culture of Larval Aquatic Organisms Aquaculture (2000) Volume: 191, Issue: 1-3, Pages: 259-270 Gildberg A., Mikkelsen H., Sandaker E., Ringø E, 1997 , Probiotic effect of lactic acid bacteria in the feed on growth and survival of fry of Atlantic cod (Gadus morhua) Hydrobiologia, Volume 352, pp 279-285(7) Holt, G.J., Cynthia K Faulk, Michael H Schwarz, 2007 A reweiw of the larviculture of 32 cobia Rachycentron canadum, a warm water marine fish Aquaculture, volume 268, issues 1-4, 22 August 2007, pags 181–187 Hitzfelder, G.M., Holt, G.J., Fox, F.M., McKee, D.A., 2006 The effect of rearing density on growth and survival of cobia, Rachycentron canadum, larvae in a closed recirculating Kenneth A W, Glenn M Hitzfelder, Cynthia K Faulk and G Joan Holt, 2007 Growth of juvenile cobia, Rachycentron canadum, at three different densities in a recirculating aquaculture system Aquaculture, Volume 264, Issues 1-4, April 2007, Pages 223-227 Kaiser, JB And G.J Holt, 2005 Spicies profile – Cobia SRAC Publication No 7202 Liao, I.C., Huei Meei Su and Emily Y Chang, 2001 Techniques in finfish larviculture in Taiwan Aquaculture, Volume 200, Issues 1-2, 15 August 2001, Pages 1-31 Le Xan, 2005 Advances in the seed production of Cobia in VietNam Nancy J B.P, Robin, O and Jeffrey M.L, 2001 Reproductive biology of Cobia Rachycentron canadum, from coastal waters of the southern United States Fish bull 96: 15-28, 2001 Liao, l., Su, H., Chang, E., 2001, Techniques in finfish larviculture in Taiwan Aquaculture 200, 1-31 Nguyen Huu Dung, 2008 Marine fish in VietNam Aquculture Asia Pacific (6) 23-24 Nguyen Quang Huy, 2000 Status of spawning and culturing Cobia, rachycentrum canadum Ricardo V.rodrigues, Michael H Schwarz, Brendan C Delbos, Luis A.Sampaio Acute toxicity and sublethal effects of ammonia and nitrite to juvenile cobia, rachycentrum canadum Rotman, R., Benetti, D.D., DeMicco, E., Orhun, M.R., 2005 Larval rearing of spotted seatrout Cynosciaon Nebulosus (Sciaenidae), using probiotics as microbial control agent J Aqac Trop 20 (2), 175-184 Xu Geng, Xiao-Hui Dong, Bei-Ping Tan, Qi-Hui Yang, Shu-Yan Chi, Hong-Yu Liu, Xian-Qin Liu,2011 Effects of dietary chitosan and Bacillus subtilis on the growth 33 performance, non-specific immunity and disease resistance of cobia, Rachycentron canadum Werich, C., Smith, T., Stokes, A., Denson, M., Jenkins, W., 2004 Pond rearing of larval and juvenils cobia (Rachycentron canadum) in the southeastern United States I appl Aquac 16, 27-44 http://www.fao.org/fishery/culturedspecies/Rachycentron_canadum/en http://www.sciencedirect.com/science/article/pii/0044848694904413 http://www.albertaclassic.com/probiotics.php http://www.sinhhocvietnam.com/forum/showthread.php?t=17081 http://books.google.com.vn/books?id=Jpyt_AzShxMC&pg=PA155&dq=%28Ringo+et+a l.,+1995%29.&hl=vi&sa=X&ei=pjv9UK2MOsqciAfzlIGgCA&ved=0CCsQ6AEwAA#v =onepage&q=%28Ringo%20et%20al.%2C%201995%29.&f=false http://vibo.com.vn/NewsDetail.aspx?newsId=85) 34 Appendix Physical and chemical parameters of water environment during 21 days of rearing Date 04-09-12 05-09-12 06-09-12 07-09-12 08-09-12 09-09-12 10-09-12 11-09-12 12-09-12 13-09-12 14-09-12 15-09-12 16-09-12 17-09-12 18-09-12 19-09-12 Temperature oC Treatment 1.1 1.2 1.3 2.1 2.2 2.3 3.1 3.2 3.3 4.1 4.2 4.3 7a.m 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 2p.m 30.0 30.0 30.0 30.0 30.0 30.0 30.0 30.0 30.0 30.0 30.0 30.0 7a.m 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 2p.m 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 7a.m 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 2p.m 29.0 29.0 29.0 29.0 29.0 29.0 29.0 29.0 29.0 29.0 29.0 29.0 7a.m 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 2p.m 29.0 29.0 29.0 29.0 29.0 29.0 29.0 29.0 29.0 29.0 29.0 29.0 7a.m 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 2p.m 29.0 29.0 29.0 29.0 29.0 29.0 29.0 29.0 29.0 29.0 29.0 29.0 7a.m 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 2p.m 30.0 30.0 30.0 30.0 30.0 30.0 30.0 30.0 30.0 30.0 30.0 30.0 7a.m 29.0 29.0 29.0 29.0 29.0 29.0 29.0 29.0 29.0 29.0 29.0 29.0 2p.m 29.0 29.0 29.0 29.0 29.0 29.0 29.0 29.0 29.0 29.0 29.0 29.0 7a.m 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 2p.m 29.0 29.0 29.0 29.0 29.0 29.0 29.0 29.0 29.0 29.0 29.0 29.0 7a.m 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 2p.m 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 7a.m 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 2p.m 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 7a.m 26.5 26.5 26.5 26.5 26.5 26.5 26.5 26.5 26.5 26.5 26.5 26.5 2p.m 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 7a.m 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 2p.m 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 7a.m 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 2p.m 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 7a.m 26.0 26.0 26.0 26.0 26.0 26.0 26.0 26.0 26.0 26.0 26.0 26.0 2p.m 29.0 29.0 29.0 29.0 29.0 29.0 29.0 29.0 29.0 29.0 29.0 29.0 7a.m 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 2p.m 29.0 29.0 29.0 29.0 29.0 29.0 29.0 29.0 29.0 29.0 29.0 29.0 7a.m 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 35 20-09-12 21-09-12 22-09-12 23-09-12 24-09-12 Day 9/9/2012 9/16/2012 9/23/2012 Day 9/9/2012 9/16/2012 9/23/2012 2p.m 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 7a.m 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 2p.m 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 7a.m 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 2p.m 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 7a.m 27.5 27.5 27.5 27.5 27.5 27.5 27.5 27.5 27.5 27.5 27.5 27.5 2p.m 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 7a.m 26.5 26.5 26.5 26.5 26.5 26.5 26.5 26.5 26.5 26.5 26.5 26.5 2p.m 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 28.0 7a.m 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 27.0 2p.m 28.5 28.5 28.5 28.5 28.5 28.5 28.5 28.5 28.5 28.5 28.5 28.5 4.2 9.1 9.1 9.1 9.2 9.2 9.2 4.3 9.1 9.1 9.1 9.2 9.2 9.2 pH 7a.m 2p.m 7a.m 2p.m 7a.m 2p.m NO2mg/L 7a.m 7a.m 7a.m 1.1 9.1 9.1 9.2 9.2 9.2 9.2 1.2 9.1 9.1 9.2 9.2 9.2 9.2 1.3 9.1 9.1 9.2 9.2 9.2 9.2 2.2 9.1 9.1 9.1 9.3 9.3 9.3 2.3 9.1 9.1 9.1 9.3 9.3 9.3 3.1 8.8 9.1 9.1 9.2 9.2 9.2 3.2 8.8 9.1 9.1 9.2 9.2 9.2 3.3 8.8 9.1 9.1 9.2 9.2 9.2 4.1 9.1 9.1 9.1 9.2 9.2 9.2 1.1 1.2 1.3 2.1 2.2 2.3 3.1 3.2 3.3 4.1 4.2 4.3 0.0 2.0 4.0 0.0 2.0 4.0 0.0 2.0 4.0 0.0 2.5 3.0 0.0 2.0 3.0 0.0 2.0 3.0 0.0 1.5 2.5 0.0 1.5 2.5 0.0 1.5 2.5 0.0 2.0 3.0 0.0 2.0 3.0 0.0 2.0 3.0 1.1 1.2 1.3 2.1 2.2 2.3 3.1 3.2 3.3 4.1 4.2 4.3 30 50 30 50 30 50 35 50 30 50 30 50 25 40 25 40 25 40 30 40 30 40 30 40 2.1 2.2 2.3 3.1 3.2 3.3 4.1 4.2 4.3 0.70 0.75 0.75 0.75 0.80 0.75 0.75 0.75 0.80 0.25 1.00 0.75 0.25 1.00 0.75 0.25 1.00 0.75 0.60 1.00 1.00 0.60 1.00 1.00 0.60 1.00 1.00 9/9/2012 9/16/2012 9/23/2012 NO3mg/L 7a.m 7a.m 7a.m Day 9/9/2012 9/16/2012 9/23/2012 NH4+ 1.2 1.3 mg/L 1.1 7a.m 0.50 0.50 0.50 7a.m 0.50 0.50 0.50 7a.m 1.00 1.00 1.00 Day 2.1 9.1 9.1 9.1 9.3 9.3 9.3 36 Length of 30 larvae (mm) collected in the weeks Number 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Length of larvae day 1.1 1.2 1.3 2.1 5 7.5 4 6 6 7.5 5 7.5 6 5 7.5 7.5 6 5 6 7.5 7.5 7.5 7.5 6 5 5 5 7.5 5 7.5 5 5 7.5 6 6 5 6 7.5 7.5 5 7.5 5 5 7.5 5 10 5 2.2 6 7.5 6 5 7.5 6 7.5 5 6.5 5 2.3 6 5 7.5 6 6 7.5 6 5 7.5 5 6 37 3.1 7.5 7.5 5 5 6 7.5 6 7.5 5 7.5 7.5 7.5 3.2 6 5 6 7.5 7.5 5 5 5 5 6 6 7.5 3.3 5 5 6 7.5 5 6 6 7.5 7.5 7.5 7.5 6.5 7.5 5 4.1 7.5 10 5 6 7.5 7.5 6 7.5 6 10 4.2 7.5 7.5 7.5 7.5 7.5 6 5 7.5 7.5 6 4 4.3 4 5 7.5 5 7.5 7.5 6 5 5 7.5 5 7.5 Number 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 1.1 12 18 12 14 10 8 18 11 10 8 14 16 20 12 12 12 14 12 13 12 20 18 Length of larvae day 14 1.2 1.3 2.1 10 20 22 12 12 13 14 8 10 12 13 11 15 10 15 18 6 12 13 10 21 10 18 12 18 14 12 10 12 10 18 16 14 15 8 18 12 20 10 18 14 13 10 12 10 12 22 12 12 10 12 10 12 10 10 10 2.2 24 16 12 12 13 12 10 12 12 10 10 11 12 10 12 12 14 12 10 8 10 10 18 10 16 2.3 14 16 16 12 14 10 8 12 14 15 10 10 10 12 19 12 12 8 14 12 10 12 38 3.1 10 12 17 12 12 10 12 15 15 12 10 10 10 12 6 12 14 12 12 12 15 15 10 3.2 16 11 23 18 15 18 16 12 17 11 10 12 12 10 10 15 13 15 10 10 8 10 10 15 12 3.3 10 13 10 15 15 12 10 12 12 12 12 14 18 18 8 12 10 16 20 8 18 12 12 4.1 20 12 18 10 12 13 16 17 12 6 15 12 10 12 10 10 18 13 12 18 13 4.2 10 11 12 16 10 14 12 10 12 15 10 13 18 12 12 13 10 18 16 4.3 20 18 12 12 12 12 8 10 10 13 18 11 13 10 20 17 18 18 5 10 5 12 18 Number 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 1.1 21 10 9.5 17.5 21 20 22 19 12 20 7.5 18 19 10 10 20 25 10 17.5 10 10 17.5 18 18 27.5 15 1.2 11 7.5 10 15 7.5 11 11 20 12 17.5 15 10 22.5 16 10 15 10 19 15 15 7.5 7.5 12 7.5 10 11 14 7.5 19 Length of larvae day 21 1.3 2.1 2.2 14 7.5 15 10 11 16 16 22.5 10 15 10 17.5 12.5 15 11 10 22.5 20 15 17.5 15 19 7.5 10 15 11 15 20 10 12.5 25 14 7.5 10 15 10 15 16 17.5 17.5 7.5 15 20 21 12.5 17.5 10 12.5 17.5 30 17.5 20 25 12.5 15 25 10 12.5 7.5 15 12.5 20 10 12 15 10 12 20 15 12 12.5 17.5 15 7.5 20 10 12.5 10 20 12.5 20 11 21 16 10 25 2.3 17.5 19 15 18.5 15 12 7.5 11 15 10 10 20 7.5 15 12.5 14 10 14 11 15 10 10 15 17.5 10 15 15 7.5 10 12.5 39 3.1 11 10 12.5 17.5 15 12.5 12.5 15 17.5 17.5 10 15 12.5 10 12.5 15 10 10 20 17.5 17.5 21 20 15 10 17.5 7.5 15 15 10 3.2 17.5 12.5 12.5 15 12.5 12.5 15 20 17.5 10 12.5 10 15 17.5 10 24 15 15 7.5 10 7.5 7.5 7.5 12.5 30 10 12.5 17.5 19 18 3.3 15 14 27 15 15 21 17.5 15 10 15 15 17.5 12 15 17.5 15 17.5 10 15 10 15 17.5 16 16 15 10 7.5 14 7.5 14 4.1 20 19 16 11 16 15 21 25 22 20 16 18 15 21 15 16 17 20 19 14 13 17 13 15 20 19 19.5 15 11 10 4.2 22.5 22.5 20 16 19 16 13 11 10 15 16 13 13 15 13 12.5 13 12 10 11 12 12 12.5 15 14 25 15 12 12 20 4.3 14 15 13 10 11 10 10 11 15 17 11 11 14 25 20 12 15 15 12 18 15 12 14 12 10 10 11 25 10 10 ANOVA Length1 Sum of Squares df Mean Square Between Groups 193 064 Within Groups 356 045 Total 550 11 F Sig 1.445 300 Length1 Duncan Subset for alpha = 0.05 Treatme nt N 1 5.5567 3 5.7833 5.8467 5.8833 Sig .113 ANOVA Length2 Sum of Squares df Mean Square Between Groups 1.656 552 Within Groups 4.718 590 Total 6.374 11 40 F Sig .936 467 Length2 Duncan Subset for alpha = 0.05 Treatme nt N 1 10.7333 11.3467 11.6433 3 11.6433 Sig .209 ANOVA Length3 Sum of Squares Between Groups df Mean Square 2.539 846 Within Groups 17.851 2.231 Total 20.390 11 Length3 Duncan Subset for alpha = 0.05 Treatme nt N 1 13.8567 14.1800 3 14.3033 15.1067 Sig .362 41 F Sig .379 771 ANOVA survivalrate Sum of Squares df Mean Square Between Groups 5.577 1.859 Within Groups 5.782 723 11.359 11 Total survivalrate Duncan Subset for alpha = 0.05 Treatme nt N 3.8133 4.2267 4.2267 4.8800 4.8800 3 Sig 5.6133 179 092 42 F 2.572 Sig .127 [...]... Objectives of the study The specific objectives are to evaluate the effects of probiotics to the growth and survival rates of cobia larvae in order to determine suitable level of probiotics 1.3 Content of the study Study on the effect of probiotics supplemented in water on the growth and survival rate of cobia (Rachycentron canadum) larvae 11 CHAPTER II LITERATURE REVIEW 2.1 Biological f eatures of cobia. .. Crassostrea gigas larvae The effect of probiotics containing lactic acid bacteria in the feed was conducted by Gildberg et al (1997) on the subject was Atlantic cod fry Significant effect of Aquazyn TM-1 commercial probiotics on the water quality and growth of Cyprinus carpio was conducted by Sharma and Bhukhar (2000) For crustaceans, study on probiotics effect on growth of P monodon was investigated by... body length of larvae among the treatments (p>0.05) In this stage of nursing, cobia fry had a fast growth and probiotics concentration had no effect on length gain Daniel D.Denetti et al,(2008) had studied on intensive larval husbandry and fingerling production of cobia showed that cobia fry’s lengths were ranged form 1.5 to 2.0 cm at 20 -22 dph Hassler and Rainville (1975) pointed out that growth was... (7a.m and 5p.m) Thermometer Nitrite Once a week (7a.m and 5p.m) Test kit TAN Once a week (7a.m and 5p.m) Test kit Nitrate Once a week (7a.m and 5p.m) Test kit Salinity Once a week (7a.m and 5p.m) Salinmeter Growth and survival rate of larvae: Larvae samples from all rearing tanks were taken once a week (30 larvae / tank) to measure body length and to define daily length gain (DLG) and specific growth rate. .. Values in the collume with different letters are significant difference (p< 0.05) 29 CHAPTER V CONCLUSIONS AND RECOMMENDATIONS 5.1 Conclusions Application of probiotics during larval rearing of cobia gave in promising results as it reduced Nitrite concentration, improved survival rates and reduced size variation of larvae However, probiotics improved relatively but not significanlly the growth of larvae. .. dosage of probiotics is from 0.5-1g/m3 applying every three days due to high survival rates 5.2 Recommendations Further studies on application of different types and using methods of probiotics to cobia larval rearing is needed Further studies on nutrition and feeding of cobia larvae for better survival rate and growth are necessary 30 References Benetti, D.D., Bruno Sardenberg, Aaron Welch, Ronald... to increase the survival rate of cobia larvae was developed in Taiwan Follow the trend of cobia culture, many countries in the world especially Asia have started to concern and did research on juvenile production in hatchery and grow out production in cages In Vietnam, studies on marine culture and hatchery are still limited, just begun from the 1990s In 2005, the total production of marine production... digestive tract of fish contains a much higher number of microorganisms than the surrounding water, as many as 108 cell g-1 (Ringo et al., 1995) As a study of Hansen and Olafsen (1998) most important being are Pseudomonas, Cytophaga and Flexibacter which were colonized in the gastrointestinal tract of larvae Probiotics administration to fin fish growth and development as well as survival rate positively... Xu Geng, Xiao-Hui Dong, Bei-Ping Tan, Qi-Hui Yang, Shu-Yan Chi, Hong-Yu Liu, Xian-Qin Liu,2011 Effects of dietary chitosan and Bacillus subtilis on the growth 33 performance, non-specific immunity and disease resistance of cobia, Rachycentron canadum Werich, C., Smith, T., Stokes, A., Denson, M., Jenkins, W., 2004 Pond rearing of larval and juvenils cobia (Rachycentron canadum) in the southeastern... the status of cobia production and study in the world Cobia study was first conducted by collecting the wild cobia eggs in the off coast of North Carolina (FAO, 1990) According to many studies, cobia is a significantly potential species for aquaculture because of fast growth and good flesh quality Then, many researches about cobia grow out and reproduction was conducted from 1980-1990 in USA In 1997,