Dirasat, Pure Sciences, Volume 37, No. 2, 2010

Growth and Survival of Golden Grey ( aurata RISSO, 1810) in Different Salinty Levels

Abd el-Latif Shaaban Ali and Adib Ali Saad*

ABSTRACT The effect of different salinity levels on the growth performance, feed conversion ratio and survival ratio of (Mugil aurata), was investigated .

Nine hundred fries (5.74 ± 0.28 g) were stocked in 9 (4 m3) (2×2 ×1 m) concrete tanks with salinities of 38%, 18% and 0%, respectively and fed 3 times for a period of 60 days.

Final body weight and SGR were measured at the end of the incubation period and were significantly lower at C (0%) than A (38%) and B (18%) treatments (P> 0.05). The results indicate that Golden grey mullet fry show best performance when reared at a salinity of 18%.

Keywords: Golden grey mullet, Mugil aurata, salinity, growth, survival ratio.

1. INTRODUCTION Mediterranean aquaculture are still obtained from wild stocks. Only in Egypt about one billion of wild grey Aquaculture plays increasingly important role in the mullet fry have been collected during the last decade to world fishery production. It has been the world's fastest supply aquaculture in marine, brackish and fresh waters growing food production systems for the past decade. The (Sadek and Mires, 2000). Fish development, growth and total world fish production of aquaculture increased from survival are influenced by various physiological factors about 35.5 million tons in 2000 to about 51.7 million tons among which water salinity is an important parameter. in 2006 (FAO, 2008). The increase was a result of Many studies have indicated that the various intensification of production of the existing farms and the developmental stages during fish embryogenesis depend expansion of areas under cultivation. on water salinity. Salinity also plays a key role in growth Grey mullets are mainly catadromous fish family, control, influencing growth rate, metabolic rate, feed excluding a few member species. They live in schools on intake and feed conversion. Mullets is euryhaline capable the coasts, lagoons and rivers of tropical and subtropical of living in environments of different salinities ranging waters (McDowal, 1988). They are important food fishes. from 0% to 60-70%, (Collins, 1985). In low salinity The euryhalinity, eurythermality and their simpler diet, as adapted fish, the passive outward flux of ions such as Na+ well as the rapid growth of some species, have made and Cl- from the fish to the external medium, via the gills, them the object of aquaculture in many parts of the world, fasces, and renal system, must be overcome by active including the Mediterranean (Oren, 1981). In 2003, uptake of ions (e.g., Na+, Cl-, K+, and Ca2+) from the 42,738 tons of grey mullets (about 60% of their total water and/or from the diet (Schmidt-Nielsen, 1997). The production) were produced by aquaculture in marine, gill is a major osmoregulatory organ in fish, undergoes brackish and inland waters of countries bordering the large morphological changes, even at low salinities (Laiz- Mediterranean and the Black Sea (FAO, 2005). Artificial Carrion et al., 2005). Adaptation to salinity regimes breeding of grey mullet has been practiced since the markedly lower than sea water is an important 1970s (Kuo et al., 1973), but most of the fries for the physiological ability in many marine fish species (Blaber, 1997). * Agricultural Research Centre of Lattakia; Laboratory of There are 8 mullet species in Syrian water 7 species in Marine Sciences and Aquatic Environment; and Faculty of Agriculture, Tishreen University, Lattakia, Syria. Received marine and brackish water (Hammoud, 1996), and one on 9/11/2009 and Accepted for Publication on 11/4/2010. species in fresh water (Bekman, 1962), but any mullet has

- 25 - © 2010 DAR Publishers/University of Jordan. All Rights Reserved. Growth and Survival… Abd el-Latif Shaaban Ali and Adib Ali Saad not yet been cultured commercially there. Mullets in in nine (3 treatment ×3 triplicates) different concrete Syria generally are obtained from Mediterranean and tanks (2×2×1 m) for 60 days. All fish groups were fed inland water fisheries. adlibitum with (30% crude protein unified diet) three This study was carried out with the aim of times daily. Velocity of water entering the tanks was determining the effects of different salinity levels on 201/min. growth of Liza aurata and contributing to its culture Temperature and dissolved oxygen (DO) were researches in Syrian water. measured daily at 8 am, by the use of WTW oxi 340i oxygen meter, salinity by WTW condi 340i salinometer 2. MATERIALS AND METHODS and pH by Hanna model pH- meter. Once every 20 days, 25 fish from each tank was This study was performed at Al Sen fresh water fish removed randomly and then weighed and measured for farm in Tartus governorate, which is belonging to the their length individually. At the end of the study, growth general establishment of fishery, Syria. performance parameters and mortality were calculated Golden grey mullets 900 individual fish (5.74 ± 0.28 using the following equations. g, 8.23 ± 0.14 cm) were caught from the estuary of Al Sen River on the Mediterranean Sea shore. They were FCR = Wf/ Ww then divided into 3 groups. After that the mullets were SGR = (Ln Wt – Ln W0)/t ×100 stocked into 3 acclimating concrete tanks having water DGR = (Wt – W0)/t with salinity of 18%. The first group was acclimated M = Nd/Nt ×100 gradually to sea water within two days by changing 50% (in first day) and 100% (in second day) of the tank water Where: W: weight (g), Wf: dry feed intake (g), Ww: with sea water. The second group was acclimated to wet weight gain (g), FCR: feed conversion ratio, SGR: brackish water 18% for two days, while the third group specific growth rate (%), Wt: final weight value (g), Wo: was acclimated to fresh water within two days. Fish in all initial weight value (g), t: treatment time (day), WG: groups were not fed in the first day but were given a weight gain (g), DGR: daily growth rate (g), M: mortality small amount of food in the second day of the (%), Nd: dead fish number, Nt: total fish number. acclimation (Polat et al., 1995). Each tank was connected All statistical analyses of final weight and length with water flow through system separately, after fish values and the values of growth performance parameters were maintained there one day more because of providing of the groups were performed using Duncan Multiple of the feed intake, fish are divided into 3 equal groups Range Test in Stat View Program and 0.05 significance (100 individual fish) and the experiment was conducted level.

Table 1. Mean Body Weight of the fish Groups at Each Sampling Period. Values within the same row followed by the same superscript are not significantly different (p> 0.05)

Mean Body Weight (g) Sampling Groups Periods 20 days 40 days 60 days (days) A 7.14±0.18b 9.98±0.23b 13.44±0.11b B 8.12±0.37a 11.47±0.28a 15.72±0.41a C 6.51±0.21c 8.31±0.52c 10.14±0.73c

3. RESULTS in Table 3. The present study showed that, fish in treatment B Means of the body weight and total length of the fish (18%) had superior growth (P> 0.05), best survival rate in each sampling period are presented in Tables 1 and 2. and FCR compared to other treatments. In treatment A, FCR, SGR, DGR and survival rate values are presented weight gains, SGR, FCR, DGR and survival rate were

- 26 - Dirasat, Pure Sciences, Volume 37, No. 2, 2010 significantly higher than in treatment C (P> 0.05). By for maximum growth of Golden grey mullets fries are the comparison, treatment C had the lowest growth, survival low salinities (brackish water) 18% rather than sea water rate and FCR. 38% and fresh water 0%. The results indicate that the most favorable conditions

Table 2. Mean Total Length of fish Groups at Each Sampling Period. Values within the same row followed by the same superscript are not significantly different (p> 0.05)

Mean Total Length (cm) Sampling Groups Periods 20 days 40 days 60 days (days) A 8.82±0.14a 9.95±0.22a 10.83±0.18a B 9.13±0.12a 10.24±0.11a 11.17±0.19a C 8.26±0.25b 9.27±0.17b 10.11±0.21b

Table 3. Mean FCR, SGR, DGR, M, and WG Values of the Fish in Each Group. Values within the same row followed by the same superscript are not significantly different (p> 0.05)

Groups FCR SGR (%) DGR(g) M (%) WG (g)

A 2.33±0.11a 1.41±0.16a 0.12±0.02a 8±2a 7.7±0.11b

B 2.11±0.12a 1.63±0.06a 0.15±0.01a 5±3a 9.98±0.41a

C 2.5±0.18b 0.95±0.17b 0.07±0.03b 29±6b 4.4±0.73c

4. DISCUSSION ppm. It has been reported that, mullets are sensitive to low oxygen concentration less than 4 ppm (Salama, The present work represents the first study on the 1994). Water in the experimental tanks was slightly effect of salinity levels on the growth of Golden grey alkaline (pH 7,5-8,9), which may be due to the mullets (Mugil aurata). Previous studies on mullets in phytoplankton activity and the utilization of CO2 and Syria were mainly on classification and reproductive HCO3¯. Alabaster and Lioyd (1984) reported that, water cycle and feeding habit of mullets (Hammoud and Saad, having pH between 6.5 and 9.0 is most suitable for fish 1996, Hammoud, 1996), in sea water. production. Accordingly, it can be stated that, water in Studying the characteristics of water in the the present study was proper for the fish growth. experimental tanks is very important to assessing its Difference in values of temperature, dissolved oxygen suitability for fish rearing. Water temperature must and pH in all experimental water tanks were found suitable for the biological requirements of fish, because insignificant statistically (P>0,05). the influence of temperature is significant on fish feeding Tolerance of mullets to fresh or salt water during and growth (Boyd, 1979). In the present study minimum acclimatization is limited according to species (Cardona, water temperature value was reached in May (24.41± 2000), fish size (Nordlie et al., 1982), water temperature 0.33˚C) while the maximum temperature was measured and salinity (Atay, 1994). in June (25.52 ± 0.65˚C). This is in agreement with The results of the present study showed that, Golden (Nagel, 1979) who reported that, water temperature over grey mullet (Mugil aurata) was able to acclimate to 18˚C was best for fish survival and growth. different salinity levels of rearing water and began to feed Dissolved oxygen (DO) values in the experimental in a short time. In general, individuals reared in water tanks seemed to be suitable and ranged from 6.74-7.34 having 18% salinity had superior growth to the other

- 27 - Growth and Survival… Abd el-Latif Shaaban Ali and Adib Ali Saad treatments (P> 0.05). They also showed the best survival salt water in a hot period between June and August rate and FCR. The reasons may be due to greenish water (Mamali, 1993). The ability to adapt to lower salinities is in B treatment tanks which resulted from mixed fresh based on the rapid reversion of the osmoregulatory water and sea water. It was very suitable for fish growth mechanism on the cell membrane level (Davenport and and rearing. Bard et al. (1976) mentioned that, when Stene, 1986). Differences in survival ability are attributed ponds were well fed or fertilized, the color of the water to the ability of fish to conclude this reversion turned into dark green and became satisfactory for fish successfully as quickly as possible. The iso-osmotic point rearing. It was noticed that, Chironomid midges were for marine species between body fluids and the sea water found in high density at the surface of water in B was found to be around 10 ± 2% below which the treatment tanks. The results of the present work is reversion of the osmoregulatory mechanism occurs agreement with the general knowledge on the biology of (Brett, 1979). this species, which may indicates that, Golden grey In conclusion it can be stated that although, fresh mullet, usually lives inshore (in sea water), enters lagoons water rearing of mullets and its polyculture has been and estuaries, but rarely moves into freshwater (Ben- performed in some European and Far East countries and Tuvia,1986). Bozkurt and Seçer (2001) mentioned that, Egypt, mullets culture in Syria has not been carried out growth of Mugil capito increases when water temperature yet and therefore, this study is expected to help in increases and salinity decreases, and post larva of Mugil developing a system for mullet rearing culture project, capito reached the size of 1.3-2.3 mm to 6.7mm (4.17 g) and initiate more future research on this field. between 8-26˚C water temperature and 28-38% salinity during a one year period. Bozkurt and Seçer (2001), Acknowledgement reported that Alpbaz and Hoşsucu (1979) found that, M. The authors wish to express their thanks to the staff capito fries grew out from 0.64 g to 12.58 g body weight members in the general establishment of fishery, Jablah, in 17˚C water temperature and 15.1% salinity during a Syria and staff members in Al Sen fresh water fish farm period of 5 months. M. aurata fries grew out from 23.9 g in Tartus governorate for the facilities offered throughout to 70.47 g body weight with 95% survival rate in cages in this work.

REFERENCES Bozkurt, Y., Seçer, S. 2001. Effects of Usage in Different Proportion to Manufactured Feed and Fish Meat on Alabaster, J.S. and Lioyd, R. 1984. Water quality criteria for Growth Performance in Feeding of Fries of Mullet freshwater fish. Publ. Butterworths, in arrangement with (Mugil sp.) (in Turkish). XI. National Fisheries FAO. Univ. Press, Cambridge, UK. Symposium, 2001, HATAY; Atay, D. 1994. Sea fish and culture procedure (II. Press) (in Brett, J.R. 1979. Environmental factors and growth. In: Fish Turkish). Publication of Fisheries Department of Physiology, Vol. III (ed. by W. S. Hoar and D.J. Agricultural Faculty, University of Ankara: 1352, Book: Randall), 599 – 675. Academic Press, New York. 392, ANKARA, 316. Cardona, L. 2000. Effects of Salinity on The Habitat Bard, J., Dekimp, P. and Lazard, J. 1976. Handbook of Fish Selection and Growth Performance of Mediterranean Culture. Center Technique Forestior Tropical Nogent- , Mugil cephalus (Osteichthyes, Sur-Marne, France, 165. Mugilidae). Estaurine, Coastal and Shelf Science, 50 (5): Beckman,W.C. 1962. the freshwater fishes of Syria and their 727-737. general biology and management.– FAO Fishery Collins, M.R. 1985. Species Profiles: Life Histories and Biology, Technical Paper 8: v + 297 Roma. Environmental Requirements of Coastal Fishes and Blaber, S.J.M. 1997. Fish and Fisheries of Tropical Invertebras, STRIPED MULLET. Biological Report 82 Estuaries. London: Chapman & Hall. (11.34), TR EL-82-4, Department of Zoology, Boyd, C.E. 1979. Water quality in warm-water fish ponds. University of Florida, Gainesville, FL, USA, 11. Auburn Univ., Agric. Exper. Station, Auburn, Alabama, Davenport, J., Stene A. 1986. Freezing resistance, 297. temperature ans salinity tolerance in eggs, larvae and

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adults of capelin, Mallotus villosus, from Balsfjord. Experimental Zoology, 303A, 563-576. Journal of the Marine Biological Association of the UK, Mamali, D. 1993. Researching of Feeding Possibilities and 66: 145 – 157. Growth of Sea Mullets in Net Cages (in Turkish); FAO. 2008. The state of Aquaculture and fisheries in the Institution of Natural Science, University of Ege, Msc world , WWW.fao.org (docrep/011/i0250e, HTM). Thesis. IZMIR. FAO. 2005. Fisheries Department, Fishery Information, Nordlie, F.G., Szelistowski, W.A., Nordlie, W. C. 1982. Data and Statistics Unit. FISH-STAT Plus: Universal Ontogenesis of Osmotic Regulation in The Striped software for fishery statistical time series [database on Mullet, Mugil cephalus. L., Journal of Fish Biology, 20 the Internet]. Version 2.3. Food and Agriculture (1): 79-86. Organization of the United Nations, Rome. 1996-2000 McDowal, R.M. 1988. Diadromy in fishes. Migrations (date of update/revision unknown; cited May. 12, 2005). between freshwater and marine environments. Available from: http://www.fao.org/fi/statist/ FISOFT/ Cambridge University Press, Cambridge, 299. FISHPLUS. Nagel, L. 1979. Aquaculture in the third world. J. of Anim. Hammoud V. 1996. Biological study of 4 species of Res. and Develop., 9: 77. Mugilidae: Liza aurata, Liza ramada, labrosus Oren, O.H. 1981. Aquaculture of Grey Mullets. Cambridge and Mugil cephalus in the coastal waters of Tartous University Press, Cambridge, 507. rigion (Syria). Msc thesis, Faculty of Sciences, Tishreen Polat, A., Tekelioðlu, N., Altun, T., Akamca, E., 1995. The University, 260. Polyculture of O. niloticus and M. saliens in Different Hammoud V., Saad, A. 1996. Reproductive cycle and Stocking Combination (in Turkish). 3rd Balkan relationship between some biological data in Liza Conference on Operational Research Proceedings, ramrda (Risso, 1826) and Chelon labrosus (Risso,1826) Thessaloniki, GREECE, 2: 992-1000. in the coastal waters of Tartous department , Syria. Sadek, S. and Mires, D. 2000. Capture of the wild finfish fry Agronomic Sciences Journal, Unioncef Arabic in Mediterranean coastal areas and possible impact on Universities, 4 (1, 2): 1-20. aquaculture development and marine genetic resources, Kuo, C.M., Shehadeh, Z.H. and Milisen, K.K. 1973. A Journal of Aquaculture – Bamidgeh, 52 (2): 77-88. preliminary report on the development, growth and Schmidt-Nielsen, K. 1997. Water and osmotic regulation. In: survival of laboratory reared larvae of the grey mullet, Schmidt-Nielsen, K. (Ed.), Physiology Mugil cephalus L. Journal of Fish Biology, 5: 459- 470. Adaptation and Environment, fifth edition, Cambridge Laiz-Carrion, R., Guerreiro, P.M., Fuentes, J., Canario, University Press, 301-354. A.V.M., Martin del Rio M.P. that Mancera, J.M. 2005. Salama, M.E. 1994. Mixed culture of mullet, Nile tilapia, Branchial osmoregulatory response to salinity in the carp and silver carp under different management gilthead sea bream, Sparus auratus. Journal of regimes. Delta J. of Sci., 18 (3): 191-209.

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ﺘﺄﺜﻴﺭ ﺍﻟﻤﻠﻭﺤﺔ ﻋﻠﻰ ﻜﻔﺎﺀﺓ ﺍﻟﻨﻤﻭ ﻋﻨﺩ ﺍﺴﻤﺎﻙ ﺍﻟﺒﻭﺭﻱ ﺍﻟﺩﻫﺒﺎﻥ (Mugil aurata RISSO, 1810)

ﻋﺒﺩ ﺍﻟﻠﻁﻴﻑ ﺸﻌﺒﺎﻥ ﻋﻠﻲ ﻭﺃﺩﻴﺏ ﻋﻠﻲ ﺴﻌﺩ*

ﻤﻠﺨﺹ

ﺘﻤﺕ ﺩﺭﺍﺴﺔ ﺘﺄﺜﻴﺭ ﺍﻟﻤﺴﺘﻭﻴﺎﺕ ﺍﻟﻤﺨﺘﻠﻔﺔ ﻟﻤﻠﻭﺤﺔ ﺍﻟﻤﻴﺎﻩ ﻋﻠﻰ ﻜﻔﺎﺀﺓ ﺍﻟﻨﻤﻭ ﻭﻤﻌﺩل ﺍﻟﺘﺤﻭﻴل ﺍﻟﻐﺫﺍﺌﻲ ﻭﻤﻌﺩل ﺍﻟﺒﻘﺎﺀ ﻋﻠﻰ ﻗﻴﺩ ﺍﻟﺤﻴﺎﺓ ﻋﻨﺩ ﺃﺴﻤﺎﻙ ﺍﻟﺒﻭﺭﻱ ﺍﻟﺩﻫﺒﺎﻥ Mugil aurata. ﻭﻀﻌﺕ 900 ﺃﺼﺒﻌﻴﺔ ﻤﻥ ﺃﺴﻤﺎﻙ ﺍﻟﺒﻭﺭﻱ ﺍﻟﺩﻫﺒﺎﻥ ﺒﻭﺯﻥ (5.74 ± 0.28 ﻍ) ﻓﻲ (9) ﺃﺤﻭﺍﺽ ﺇﺴﻤﻨﺘﻴﺔ ﻤﺘﺴﺎﻭﻴﺔ ﺒﺎﻟﺤﺠﻡ 3 (4ﻡ ) (2 × 2 × 1 ﻡ) ﻓﻲ ﻤﻴﺎﻩ ﻤﻠﻭﺤﺘﻬﺎ 38 ﺠ ﺯ ﺀ ﺍﹰ ﺒﺎﻷﻟﻑ، 18 ﺠ ﺯ ﺀ ﺍﹰ ﺒﺎﻷﻟﻑ، 0 ﺠﺯﺀ ﺒﺎﻷﻟﻑ ﻋﻠﻰ ﺍﻟﺘﻭﺍﻟﻲ ﻭﺘﻡ ﺇﻁﻌﺎﻤﻬﺎ 3 ﻤﺭﺍﺕ ﻓﻲ ﺍﻟﻴﻭﻡ ﻭﻟﻤﺩﺓ 60 ﻴ ﻭ ﻤ ﺎﹰ. ﻭﺒﻘﻴﺎﺱ ﻭﺯﻥ ﺍﻟﺠﺴﻡ ﺍﻟﻨﻬﺎﺌﻲ ﻟﻸﺴﻤﺎﻙ ﻭﻤﻌﺩل ﺍﻟﻨﻤﻭ ﺍﻟﻨﻭﻋﻲ SGR ﺘﺒﻴﻥ ﺃﻥ ﺃﺩﻨﻰ ﻗﻴﻤﻬﺎ ﻜﺎﻨﺕ ﻓﻲ ﺍﻟﻤﻌﺎﻤﻠﺔ C (0 ﺠﺯﺀ ﺒﺎﻷﻟﻑ) ﺜﻡ ﺍﻟﻤﻌﺎﻤﻠﺔ A (38 ﺠﺯ ﺀ ﺍﹰ ﺒﺎﻷﻟﻑ) ﻓﺎﻟﻤﻌﺎﻤﻠﺔ B (18 ﺠﺯ ﺀ ﺍﹰ ﺒﺎﻷﻟﻑ) ﻋﻠﻰ ﺍﻟﺘﻭﺍﻟﻲ ﻤﻊ ﻭﺠﻭﺩ ﻓﺭﻭﻕ ﻤﻌﻨﻭﻴﺔ ﺒﻴﻥ ﻗﻴﻤﻬﺎ ﺍﻟﻤﺨﺘﻠﻔﺔ (P> 0.05). ﻭﺃﻜﺩﺕ ﻨﺘﺎﺌﺞ ﺍﻟﺩﺭﺍﺴﺔ ﺃﻥ ﺃﺼﺒﻌﻴﺎﺕ ﺃﺴﻤﺎﻙ ﺍﻟﺒﻭﺭﻱ ﺍﻟﺩﻫﺒﺎﻥ ﺃﻅﻬﺭﺕ ﺃﻓﻀل ﻜﻔﺎﺀﺓ ﻨﻤﻭ ﻋﻨﺩ ﺘﺭﺒﻴﺘﻬﺎ ﻓﻲ ﻤﻴﺎﻩ ﻤﻠﻭﺤﺘﻬﺎ 18 ﺠﺯ ﺀ ﺍﹰ ﺒﺎﻷﻟﻑ.

ﺍﻟﻜﻠﻤﺎﺕ ﺍﻟﺩﺍﻟﺔ: ﺍﻟﺒﻭﺭﻱ ﺍﻟﺩﻫﺒﺎﻥ، Mugil aurata، ﺍﻟﻤﻠﻭﺤﺔ، ﺍﻟﻨﻤﻭ، ﻤﻌﺩل ﺍﻟﺒﻘﺎﺀ ﻋﻠﻰ ﻗﻴﺩ ﺍﻟﺤﻴﺎﺓ.

______* ﻤﺭﻜﺯ ﺍﻟﺒﺤﻭﺙ ﺍﻟﻌﻠﻤﻴﺔ ﺍﻟﺯﺭﺍﻋﻴﺔ؛ ﻤﺨﺘﺒﺭ ﺍﻟﻌﻠﻭﻡ ﺍﻟﺒﺤﺭﻴﺔ ﻭﺍﻟﺒﻴﺌﺔ ﺍﻟﻤﺎﺌﻴﺔ، ﻜﻠﻴﺔ ﺍﻟﺯﺭﺍﻋﺔ، ﺠﺎﻤﻌﺔ ﺘﺸﺭﻴﻥ، ﺍﻟﻼﺫﻗﻴﺔ، ﺴﻭﺭﻴﺎ. ﺘﺎﺭﻴﺦ ﺍﺴﺘﻼﻡ ﺍﻟﺒﺤﺙ 9/11/2009، ﻭﺘﺎﺭﻴﺦ ﻗﺒﻭﻟﻪ 2010/4/11.

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