Performance of Monosex Fry Production of Two Nile Tilapia Strains: GIFT and NEW GIPU

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World Journal of Fish and Marine Sciences 4 (1): 68-72, 2012 ISSN 2078-4589 IDOSI Publications, 2012 DOI: 10.5829/idosi.wjfms.2012.04.01.6245 Performance of Monosex Fry Production of Two Nile Tilapia Strains: GIFT and NEW GIPU 1 2 2 1 1 M. Shamsuddin, M. Belal Hossain, M. Mofizur Rahman, M. Asadujjaman and M. Yusuf Ali 1 Department of Aquaculture, Bangladesh Agricultural University 2 Department of Fisheries and Marine Science, Noakhali Science and Technology University Abstract: A study was conducted to know e performance of GIFT and NEW GIFU tilapia to produce monosex tilapia for a period of 4 mons from March to June, 2010 by using controlled on-station experimentation. The egg production, hatching rate and fry survival rate in bo strains were assessed to know eir performance. For monosex fry production, fertilized eggs were collected from e female mou directly from breeding hapas placed in pond and were kept in jar incubation system in hatchery. Fries were obtained after an incubation period of 90-96 hours. The highest (118.33 eggs / female of GIFT tilapia and 334.61 eggs / female of NEW GIFU tilapia) egg production was found in March and e lowest (23 eggs / female of GIFT tilapia and 28.73 eggs / female of NEW GIFU tilapia) egg production was found in May. The monly average egg production (138.34 ± 134.6725 no. / female), average hatching rate (54% ± 0.0465) and average fry survival rate (73.20 % ± 0.0564) were found in NEW GIFU tilapia which were higher an at of e GIFT tilapia strain (monly average egg production 63.08 ± 40.92 no. / female, average hatching rate 50.34% ± 0.0295 and average fry survival rate 70.21 % ± 0.0476). The androgen hormone 17-"-Meyltestosterone (MT) was administered orally to e ree day old fry at eir first feeding stage at e dose of 60 mg / kg feed. After hormone treatment, e treated fries were transferred to hapas placed in pond for furer rearing (21 days). The results demonstrate at e dose of MT-60 for 21 days was sufficient to produce 95 % male population of e GIFT strain and 99 % male population of e NEW GIFU strain. The finding of e present study suggests at e introduction of NEW GIFU tilapia strains in Bangladesh could lead to significant increase in fish production and hence e economic gains. Key words: GIFT % NEW GIFU % Egg % Meyltestosterone (MT) INTRODUCTION into is country by e United Nations International Children Emergency Fund (UNICEF) in 1974 and later by Tilapias (Cichlidae) are natives of Africa. They have e Bangladesh Fisheries Research Institute (BFRI) from been introduced into a large number of tropical and Thailand [5]. subtropical countries around e world since e 1960s Tilapia has been extensively genetically modified. [1]. Tilapia was first introduced in Bangladesh in 1954. One promising Genetically Improved Farmed Tilapia strain About 80 species of tilapia have been described out of known as GIFT [6] has been introduced in July 1994 from which 10 species are reported to be used for culture [2]. e Philippines. The GIFT (5 generation) strain was Tilapias have distributed to so many different types of developed by e International Center for Living Aquatic water, to so many different types of culture systems in e Resources Management (ICLARM) rough several world at ey have been even labeled as e aquatic generations of selection from a base population involving chicken [3]. They have good resistance to poor water eight different strains of Nile tilapia, Oreochromis quality and disease, tolerance of a wide range of niloticus [6]. It performs 60% better grow and 50% environmental conditions, ability to convert efficiently e better survival an e commercially available strains of organic and domestic waste into high quality protein, tilapia [7]. GIFT and GIFT-derived strains are now being rapid grow rate and tasty flavour [4]. The existing strain cultured widely across Asia, which today produces about Nile tilapia (Oreochromis niloticus L.) was first introduced 80% of all farmed. Corresponding Auor: M. Belal Hossain, Department of Biology, FOS, Universiti Brunei Darussalm, Brunei BE1410. 68

NEW GIFU tilapia is e 11 strain of Oreochromis niloticus was introduced in Bangladesh from China, developed by Professor Li Sifa, Shanghai Fisheries University, China. In China, experiments showed at NEW GIFU tilapia strain grew more an twice as fast as e local commercial strain. On average a 200 g breeder would produce 200-500 fry per mon. Fry production will also depend on e condition and heal of e breeders [8]. Nile tilapias (75 to 500 g) deposit from 50 to 2,000 eggs per spawn [2]. NEW GIFU tilapia strain has faster grow rates and higher survival rates, us increasing fish yields dramatically. These attributes, along wi its stable, low price, have made tilapia an extremely popular food source in Bangladesh, especially among poor consumers. Kohinoor et al. [16] studied e breeding biology and monosex male seed production of GIFT strain of Nile Tilapia (Oreochromis niloticus) in hatchery under different conditions in Bangladesh. But comparison of monosex fry production between GIFT tilapia strain and NEW GIFU tilapia strain has never been reported. So e present investigation was undertaken to find out e comparison of egg production, hatching rate, fry survival rate and percentage of monosex fry production between GIFT tilapia strain and recently introduced NEW GIFU tilapia strain in Bangladesh. MATERIALS AND METHODS The study was carried out for 4 mons from March to June, 2010 in Zubin Agro-based Industries Ltd (ZAIL), Noakhali, Bangladesh. On site experimentation include brood ponds, aquaria, incubation and hatching tanks, larval rearing tanks and hapas. Brood Stock Management Pond Preparation: The ponds were prepared by dewatering followed by sun drying. Eradication of fish left from e previous culture cycle was done. After draining e pond, lime was spread at e rate of 1kg / decimal over e pond soil and en was filled wi water. 30 kg of 16 nitrogen- 20 phosphorous- 0 potassium fertilizer was added to e pond per hectare. Sources of Brood and Stocking: For tilapia brood, GIFT strain fry was collected from Bangladesh Fisheries Research Institute (BFRI) and NEW GIFU tilapia strain fry was collected from Chaina. Fry were kept in 1 m x 1 m x 2 m hapas of 1.5-mm mesh in ponds at e rate of 400 fry per hapa. The sex ratio 3:1 (female: male) was maintained in each hapa. Table 1: Monly water quality parameters in brood ponds Variable March April May June Temperature 28-32 C 25-32 C 36-37 C 27-32 C ph 7-8 7-8 7-8 7-8 Salinity 2 ppt 3 ppt 4 ppt 2 ppt Dissolved oxygen 4-6 ppm 3.5-4.5 ppm 3-4 ppm 3-5 ppm Transparency 20 cm 25 cm 30 cm 22 cm Water Quality: The following physico-chemical parameters of water of e ponds were maintained during e period (Table 1). Feed and Feeding Schedule: A special feed enriched wi protein and vitamin E, was formulated which enhances e gonad maturation in tilapias. Feed was applied by weight at e rate of 4 % total body weight of tilapia two times daily at 09:30 am and 04:00 pm respectively. Regular Manuring: Regular manuring wi cow dung was done at 15 days interval at e rate of 5kg / decimal and fertilization was done wi urea and TSP at e rate of 100 g / decimal and 80 g / decimal respectively to stimulate e grow of plankton. Six mons aged matured GIFT and NEW GIFU tilapia strains were used as brood. Procedure of Monosex Tilapia Fry Production Egg Collection and Incubation: Adult females' mous were checked for eggs every seven days. Eggs, or fry, were placed individually in buckets and transferred to aquaria at e hatchery of e Zubin Agro-based Industries Ltd. The fertilized eggs in e incubation jars started hatching after 72 hours of stocking. About 10000 eggs were placed in each incubation jar. Water flow rough was installed in e jars from e bottom to e surface led to continuous movement of e eggs inside e jar. The hatchlings after absorption of eir yolk-sac left e incubation jars wi e water flow and were collected inside e hatching jar. Rearing in Tanks: 8 x 4 x 2.5 cubic feet tank was employed for rearing of hatchling. 40000 fry were placed in each tank or sex reversal tank. Hatchlings were fed wi 17 alpha-meyltestosterone mixed wi powdered feed immediately after absorption of eir yolk sac. Hormone was mixed at e rate of 60 mg / kg. Larvae were fed six times daily to apparent satiation at e rate of 100 % by body weight. The hatchlings were reared in tank for 3 days before transfer to e hapas set in a pond. The additional oxygen to tank was provided rough aeration for 22 hours every from water circulation obtained by motor. 69

Fry Rearing in Hapa: All e hormone treated fry from e The fecundity fluctuates widely from a few hundred rearing tank were transferred into e hapa (16 x 8 x 3.5 to several ousand eggs, depending on e size and age cubic feet in size). The mesh size of e hapa net was 1 of e female. It is reported at as e weight of GIFT mm. Fries were fed at satiation level and continued strain Oreochromis niloticus increases to a range of 180- feeding for about 3 weeks wi hormone mixed feed. 498 g, e number of eggs decreases. It means at Fry fed (first 5 days) at e rate of 30 %, second 5 days at absolute fecundity in is species is inversely correlated e rate of 20 %, ird 5 days 18 % and four 5 days at wi e weight of sexually mature females [9]. Arredondoe rate of 12 %. Figueroa and Guzman-Arroyo [11] mentioned at Hatching rate and survival rate of fry was calculated Oreochromis niloticus is a mou brooder wi small by following equations: gonads of less an 700 eggs. In is study, it was reported fecundity was higher an at observed by Hatching Rate: Amount of hatched fry / Amount of oer workers for Oreochromis niloticus. Because GIFT fertilized eggs x 100. and NEW GIFU tilapia strain have genetic upgradation. Alex Bocek [13] observed 100-200 eggs produced per Survival Rate: Amount of lived fry up to 21 days / spawn by female tilapia at 28 C. In e present study e Amount of hatched fry x 100. highest egg production was obtained in March at 28-30 C and lowest in May at 36-37 C. These effects were due to RESULTS AND DISCUSSION e roughest pond condition at is in May, ere was extremely high water temperature (36-37 C). On e oer Egg Production: Total egg production was evaluated hand, total egg production, individual egg production, from 300 females GIFT tilapia and 300 females NEW GIFU hatching rate and survival rate were higher in NEW GIFU is shown in Figure 1. It was seen at e highest egg tilapia strain an GIFT. This effect was due to e (118.33 eggs / female of GIFT tilapia and 334.61 eggs / genetically up gradation of NEW GIFU tilapia strain female of NEW GIFU tilapia) production was observed in (11 strain). March and lowest egg (23 eggs / female of GIFT tilapia and 28.73 eggs / female of NEW GIFU tilapia) production Hatching Rate: The hatching rate was evaluated from was observed in May among e GIFT and NEW GIFU 300 females GIFT tilapia and 300 females NEW GIFU is tilapia strains. shown in Figure 2. Highest eggs production was seen in NEW GIFU It was seen at, highest hatching rate (53.32 % for tilapia an GIFT tilapia. According to present study, GIFT tilapia and 58.33 % for NEW GIFU tilapia) was variation of individual eggs production was observed in observed in March and lowest hatching rate (46.30 % for GIFT and NEW GIFU tilapia. It was observed at total GIFT tilapia and 47.44 % for NEW GIFU tilapia) was highest egg production per female was observed in observed in May among e GIFT and NEW GIFU tilapia March and lowest egg production/female was observed strains. Highest hatching rate was seen in NEW GIFU in May among e GIFT and NEW GIFU tilapia strains. tilapia an GIFT tilapia. Highest eggs production/female was seen in NEW GIFU tilapia an GIFT tilapia. Survival Rate of Tilapia Fry: The survival rate was evaluated from 300 females GIFT tilapia and 300 females NEW GIFU is shown in Figure 3. It was seen at, highest survival rate was observed in March and lowest survival rate was observed in May among e GIFT and NEW GIFU tilapia strains. Highest survival rate was seen in NEW GIFU tilapia an GIFT tilapia. Survival of Oreochromis niloticus ranged from 91.5 to 97.0 % during grow-out phase. Data showed no significant relationship between survival and MT treatment concentration or duration. Soto [18] and Fig. 1: Monly produced no. of eggs / female by GIFT Vera-Cruiz and Mair [19] also concluded a similar result (indicated by black colour) and NEW GIFU tilapia by observing at MT administration has no significant (indicated by white colour) effect on survival in Oreochromis niloticus. 70

Percent of Monosex Tilapia: According to e present study, variation of monosex production (%) was observed in GIFT and NEW GIFU tilapia. 99 % monosex tilapia was found in NEW GIFU tilapia and 95 % monosex tilapia was found in GIFT tilapia. The effectiveness of sex reversal treatment depends on e species, age when hormone is administered, type and dosage of hormone, time and duration of treatment [10]. Jalbert et al. [15] reported at 100 % of male was achieved wi a hormone dose at 40mg meyltestosterone / kg feed. Kohinoor et al. [16] studied Fig. 2: Monly hatching rate of GIFT (indicated by black 17 alpha meyltestosterone was applied orally to e fry colour) and NEW GIFU tilapia (indicated by white at eir first feeding stage wi treatments- 1,2,3 and 4 at colour) e dosage of 100, 80, 60 and 40 mg / kg feed respectively, for e period of 28 days. The mean percentage of males obtained in treatments- 1, 2, 3 and 4 were 98, 97, 95 and 68, respectively. Zubin Agro-based Industries Ltd., used 60mg meyltestosterone/kg feed and achieved 95 % males from GIFT broods and 99 % males from NEW GIFU was obtained by administration of same hormone dose and same percentage of protein. This dissimilarity may be due to species age at which hormone is administered, time, duration of treatment, low feed and hormone quality and environmental factors. Percent of monosex tilapia of e study was shown in Fig. 3: Monly survival rate of GIFT (indicated by black Figure 4. colour) and NEW GIFU tilapia fry (indicated by The history of e GIFT strain has been described by white colour) Ekna and Acosta [14] and by Bentsen et al. [12]. At e time e fish were received in Malaysia e GIFT strain had undergone six generations of selection. But NEW GIFU had undergone eleven generations of selection. That s why; NEW GIFU tilapia strain had higher egg production, higher hatching rate and higher fry survival rate an at of GIFT tilapia strain. In present study, it was seen at egg production was higher in NEW GIFU tilapia an GIFT tilapia strain. It is established at egg production depends on body weight. NEW GIFU tilapia strain is larger in size an GIFT tilapia strain. So, egg production was higher in NEW GIFU tilapia an GIFT Fig. 4: Percent of monosex obtained by Zubin Agro- tilapia strain. based Industries Ltd., from GIFT tilapia and NEW GIFU tilapia strain CONCLUSION The findings of Pechsiri and Yakupitiyage [17] were The study was conducted to know e performance also similar to ese wi regard to survival rate (73.3-76.0 of monosex tilapia for a period of 4 mons from March to %) of Oreochromis niloticus. Average survival rate of fry June 2010. The study was carried out in Zubin Agro- (highest 76.08 % in GIFT, 79.96 % in NEW GIFU and based Industries Ltd. hatchery to know e monosex lowest in 64.63 % GIFT and 66.42 % in NEW GIFU). The tilapia fry production system. The highest egg lowest rate of fry survival rate in May was caused by production, hatching rate and fry survival rate of GIFT extremely high temperature. and NEW GIFU tilapia strains were found in March and 71

e lowest egg production, hatching rate and fry survival 10. Ridha, M.T. and M.P. Lone, 1990. Effect of oral rate of GIFT and NEW tilapia strains were found in May. administration of different levels of 17 alpha The highest egg production, hatching rate and survival meyltestosterone on e sex reversal, grow and rate was found in NEW GIFU tilapia strain an e GIFT food conversion efficiency of e tilapia Oreochromis tilapia strain. The hatchery used 60mg meyltestosterone spilurus in brackish water. Aquaculture Fish. Mana., / kg feed and ey get 95 % monosex tilapia from GIFT 21: 396-397. strain and 99 % monosex tilapia from NEW GIFI strain. But 11. Arredondo-Figueroa, J.L. and M. Guzman-Arroyo, variable result found in different farms. 1986. Actual taxonomic situation of e species Tilapia introduced in Mexico. An. Inst. Biol. REFERENCES U.N.A.M., Serie Zool., 56(2): 555-572. 12. Bentsen, H., et al., 1998. Environmental effects of 1. Pillay, T.V.R., 1991. Aquaculture, principles and release and dissemination of improved Nile tilapia. practices. Fishing News Books, England. Report prepared by e Agricultural University of 2. Macintosh, D.J. and D.C. Little, 1995. Brood stock Norway for e United Nations Development management and fry production of e Nile tilapia Programme. Division for Global and Interregional (Oreochromis niloticus). In: N.R. Bromage and Programmes. R.J. Roberts, (eds.). Brood fish Management and 13. Alex., B., 1999. Water Harvesting and Aquaculture Egg and Larval Quality. Blackwell Science, Oxford, for Rural Development. Auburn University: pp: 277-320. International Center for Aquaculture and Aquatic 3. Maclean, J.L., 1984. Tilapia- e aquatic chicken. Environments. ICLARM Newsletter, pp: 12-17. 14. Ekna, A.E. and B. Acosta, 1998. Genetic 4. Ballarin, J.D. and R.D. Haller, 1982. The intensive improvement of farmed tilapias (GIFT) project Final culture of tilapia in tanks raceways and cages. Croon Report, March 1998 to December 1997. ICLARM, Heln Ltd. London, pp: 265-266. Makati City, Philippines. 5. Gupta, M.V., et al., 1992. Socio-economic impact 15. Jalbert, et al., 1974. Determinisme de sexe hez Tilapia and farmer s assessment of Nile tilapia macrochir et Tilapia nilotica, Action de la (Oreochromis niloticus) culture in Bangladesh. meyltestosterone dans I alimentation des alevins International Center for Living Aquatic Resources sur la differentiation sexuelle; proportion des sexes Management (ICLARM). Philippine. Tech. Rep., dans la descendance des males inverses, Ann. 35: 50. Biol. Anim. Biochim. Biophys., 14: 729-739. 6. Ekna, A.E., et al., 1993. Genetic Improvement 16. Kohinoor, A.H.M., et al.., 2003. Breeding of biology of farmed tilapia: e grow performances of and monosex male seed production of GIFT strains eight strains of Oreochromis niloticus tested in of Oreochromis niloticus. Bangladesh J. Fish Res., different farm environments. Aquaculture, 7(2): 105-114. 111: 171-188. 17. Pechsiri, J. and A. Yakupitiyage, 2005. A comparative 7. Ekna, A.E., 1992. Genetic Improvement of Farmed study of grow and feed utilization efficiency of sex Tilapia-GIFT Phase 1 Final Report. International reversed diploid and triploid Nile tilapia, Oreochromis Center for Living Aquatic Resources Management niloticus. Aquaculture Res., 36: 45-51. (ICLARM). Metro Manila. 18. Soto, P., 1992. Effect of mestanolone (17 "- 8. Dan, N.C. and D.C. Little, 2000. The culture meylandrostan - 17 ß-ol-3-one) on sex ratio and performance of monosex and mixed-sex new-season grow of Nile tilapia (Oreochromis niloticus). MS and overwintered fry in ree strains of Nile tilapia esis. Auburn University, Alabama, US., pp: 58. (Oreochromis niloticus) in norern Vietnam, 19. Vera Cruz, E.M. and G.C. Mair, 1994. Conditions for Aquaculture, 184: 221-231. effective androgen sex reversal in Oreochromis 9. Velasco, R.R., 2003a. Reproductive biology of niloticus (L.). Aquaculture, 122: 237-248. tilapias. In: Training manual on brood stock management and sex reversal of tilapia using GIFT protocol. GIFT Foundation International Inc., pp: 1-12. 72