This study was undertaken to determine the combined effects of temperature and salinity on the incubation time and hatching rate of Penaeus semisulcatus eggs in controlled laboratory conditions. Fertilized eggs, from a female caught in nature and spawned in our laboratory, were stocked in 2-l round bottom glass flasks and received one of nine temperature (24, 28 and 32°C) and salinity (30, 35 and 40 ppt) combinations. The eggs hatched in all treatments. The hatching rate increased as salinity increased and was highest at 24°C. In terms of hatching rate, the best combinations in descending order were 24°C at 40 ppt, 32°C at 40 ppt and 28°C at 40 ppt. However, the incubation time was longer at 24°C (17.5 h) than at 28°C (14.5 h) or 32°C (11.5 h)

Aktas, M.

Eroldogan, O.T.

Kumluo, M.

eVols at University of Hawaii at Manoa

The Open Access Israeli Journal of Aquaculture – BamidgehAs from January 2010 The Israeli Journal of Aquaculture - Bamidgeh (IJA) will be published  exclusively  as  an  on-line  Open  Access  (OA) quarterly  accessible  by  all AquacultureHub  (http://www.aquaculturehub.org)  members  and  registered  individuals and institutions.  Please visit our website (http://siamb.org.il) for free registration form, further information and instructions.  This transformation from a subscription printed version to an on-line OA journal, aims at supporting the concept that scientific peer-reviewed publications should be made available to all, including those with limited resources. The OA IJA does not enforce author or subscription fees and will endeavor to obtain alternative sources of income to support this policy for as long as possible.Editor-in-ChiefDan Mires Editorial BoardSheenan Harpaz Agricultural Research OrganizationBeit Dagan, IsraelZvi Yaron Dept. of ZoologyTel Aviv UniversityTel Aviv, IsraelAngelo Colorni National Center for Mariculture, IOLREilat, IsraelRina Chakrabarti Aqua Research LabDept. of ZoologyUniversity of DelhiIngrid Lupatsch Swansea UniversitySingleton Park, Swansea, UKJaap van Rijn The Hebrew University Faculty of AgricultureIsraelSpencer Malecha Dept. of Human Nutrition, Food and Animal SciencesUniversity of HawaiiDaniel Golani The Hebrew University of JerusalemJerusalem, IsraelEmilio Tibaldi Udine UniversityUdine, ItalyCopy Editor Ellen Rosenberg Published under auspices ofThe Society of Israeli Aquaculture and Marine Biotechnology (SIAMB), University of Hawaii at Manoa Library andUniversity of Hawaii Aquaculture Program in association withAquacultureHub http://www.aquaculturehub.org              ISSN 0792 - 156X Israeli Journal of Aquaculture - BAMIGDEH.PUBLISHER: Israeli Journal of Aquaculture - BAMIGDEH -Kibbutz Ein Hamifratz, Mobile Post 25210, ISRAELPhone: + 972 52 3965809http://siamb.org.il The Israeli Journal of Aquaculture – Bamidgeh 56(2), 2004, 124-128.124COMBINED EFFECTS OF TEMPERATURE AND SALINITY ONEGG HATCHING RATE AND INCUBATION TIME OF PENAEUS SEMISULCATUS (DECAPODA: PENAEIDAE)M. Aktas*Faculty of Fisheries, Mustafa Kemal University, 31040 Serinyol, Hatay, TurkeyO.T. Eroldogan and M. KumluoFaculty of Fisheries, Çukurova University, 01330 Balcalı, Adana, Turkey(Received 16.9.03, Accepted 27.12.03)Key words: hatching, Penaeus semisulcatus, salinity, temperatureAbstractThis study was undertaken to determine the combined effects of temperature and salinity onthe incubation time and hatching rate of Penaeus semisulcatus eggs in controlled laboratoryconditions. Fertilized eggs, from a female caught in nature and spawned in our laboratory, werestocked in 2-l round bottom glass flasks and received one of nine temperature (24, 28 and32°C) and salinity (30, 35 and 40 ppt) combinations. The eggs hatched in all treatments. Thehatching rate increased as salinity increased and was highest at 24°C. In terms of hatching rate,the best combinations in descending order were 24°C at 40 ppt, 32°C at 40 ppt and 28°C at 40 ppt. However, the incubation time was longer at 24°C (17.5 h) than at 28°C (14.5 h) or 32°C(11.5 h).IntroductionOptimum egg incubation conditions are impor-tant for hatchery success. Salinity and tem-perature are two of the most important envi-ronmental factors affecting the hatching rateand time of eggs. In nature, spawning, hatch-ing and larval stages of penaeid shrimps gen-erally take place in oceanic sea waters wheresalinity and temperature do not fluctuate con-siderably. It is commonly accepted thatpenaeid eggs hatch between 12 and 17 h at*  Corresponding author. Tel.: +90-326-2455815, fax: +90-326-2455807; e-mail: maktas@mku.edu.tr125oceanic salinities and 25-28°C. However, littleis known about the combined effects of tem-perature and salinity on the hatching rate andtime of penaeid eggs. The optimal tempera-ture and salinity combination for egg incuba-tion is species-specific (Preston, 1985) andthese levels must be determined for eachspecies.A limited number of studies have focusedon the effects of salinity and temperature sep-arately. Adequate egg incubation temperaturefor P. monodon was suggested to be 26-29°C(Hillier, 1984; Primavera, 1985). Primavera(1985) recorded that an increase in tempera-ture from 23°C to 28°C or 33°C significantlydecreased the incubation period but had noeffect on the hatching rate. This author report-ed high hatching rates at 33 ppt between 23and 33°C but weak larval activity after hatch-ing at 23 ppt regardless of the experimentaltemperature. The eggs of Fenneropenaeusindicus and P. semisulcatus at 20-25 pptexhibited retarded development and evenburst at 10-15 ppt (Tseng and Cheng, 1981;cited in Primavera, 1985). Nisa and Ahmed(2000) found that the best egg hatching rate ofF. merguiensis, F. penicillatus, Metapenaeusaffinis and Parapenaeus stylifera took place at35 ppt, and that the hatching rate decreasedgradually with decreasing salinity until nohatching occurred at 20-25 ppt for P. stylifera.Most recently, Zacharia and Kakati (in press)studied the combined effects of temperatureand salinity on the hatching success of F.merguiensis and found that the highest per-cent hatch was obtained at 33°C and 35 ppt(87%), followed by 29°C and 35 ppt (82%). The hatching rate of eggs of eyestalk-ablated females of P. semisulcatus was47.82% at 38 ppt and 28°C (Aktas and Kumlu,1999) and 90.3% at 22.4-27.5°C (Browdy andSamocha, 1985). To date, no studies havebeen carried out to determine the optimumcombination of salinity and temperature for P.semisulcatus, an Indo-Pacific species distrib-uted along the coast of the easternMediterranean and one of the most importantcommercial species in this region. Kumlu etal. (1999a) observed that the spawning sea-son of P. semisulcatus extends into coolmonths, hence this species might have adapt-ed to subtropical conditions. A better under-standing of the combined effects of tempera-ture and salinity on the hatching rate and incu-bation time for eggs of this penaeid shrimp isimportant to determine conditions for optimalhatchery production. Therefore, this studywas carried out to determine the salinity andtemperature combination that produces thebest hatching rate and shortest egg incuba-tion time for P. semisulcatus. Materials and Methods The study was undertaken at the MarineResearch Station of the Faculty of Fisheries,University of Çukurova, Yumurtalık, Turkey.The eggs were obtained from a female caughtoff Yumurtalık Bight in the northeasternMediterranean, that maturated in the stationand spawned in a 100-l tank at 39 ppt and28°C. The fertilization rate was determinedunder a microscope. Ten minutes afterspawning, the eggs were pooled in a 100-µmsieve and acclimated to the experimentalsalinities (30, 35 and 40 ppt) and tempera-tures (24, 28 and 32°C) by lowering orincreasing the salinity/temperature at a rate of2 ppt or 1°C per 15 min, respectively. Salinitywas adjusted by adding fresh water (wellwater) that was prepared and aerated beforeuse or sea salt (Instant Ocean, USA) asdescribed in Kumlu et al. (2000, 2001). Theeggs were stocked into 2-l round bottom glassflasks in three replicates of each combinationat a density of 50 eggs per liter. Salinity and temperature were measuredwith a digital salinometer (YSI 30, USA).Temperatures for each treatment were main-tained in three thermostatically controlledwater baths (±0.5°C). Gentle aeration (4 bub-bles/sec) was maintained through a siliconrubber tube with a glass rod at the tip. The hatching time (incubation duration)was determined when 50% of the eggs ineach flask hatched. When the hatching fin-ished, nauplii and eggs were collected with a100-µm mesh and counted to determine thehatching rate. Hatching rates were analyzed by two-wayANOVA. Differences were considered signifi-Effects of temperature and salinity on egg hatching in Penaeus semisulcatuscant at a 0.05 probability level by Scheffe’stest after normality and homogeneity of thedata were checked in the Minitab StatisticalPackage. ResultsSalinity and temperature and their interactionhad significant influences on the hatchingrate, but salinity appeared to have a more pro-found affect than temperature (Table 1). Eggsincubated at 40 and 35 ppt had higher(p<0.05) mean hatching rates (87.33-82.28%)than those incubated at 30 ppt (49.47%). Incontrast to salinity, eggs incubated at the twohigher temperatures had lower mean hatchingrates than those incubated at the lowest tem-perature.The eggs incubated at 24°C and 40 ppthad the best hatching rate (p<0.05). The low-est hatching rates were obtained at 30 ppt and28°C or 32°C (p<0.05). Following hatching,larval activity was poor at 30 ppt regardless ofthe temperature.Results indicate that successful egg incu-bation of P. semisulcatus can take place overa wide range of salinity and temperature, butthe best salinity and temperature combinationis 24°C and 40 ppt. DiscussionThe present study shows that salinity had agreater influence than temperature on thehatching rate of P. semisulcatus. The besthatching success was obtained at the highestsalinity (40 ppt). Eggs incubated at 30 ppt hadthe lowest hatching rate. These findings agreewith those of Nisa and Ahmed (2000) whostudied the effects of six different salinities(20-45 ppt) on the eggs of four penaeidshrimps, F. merguensis, F. penicillatus, M.affinis and P. stylifera, in laboratory condi-tions. They stated that the best hatching suc-cess was at 35 ppt for all the species, hatch-ing success decreased with the decrease insalinity, and no hatching occurred at 20-25 pptfor P. stylifera. Zacharia and Kakati (in press)126 Aktas et al.Temperature Salinity Hatching rate Hatching time Larval activity(°C) (ppt) (%) (h)24 30 84.00±7.11a 17.5 Poor35 82.00±4.89a 17.5 Good40 91.33±1.68a 17.5 Good28 30 18.67±9.29bc 14.5 Poor35 81.00±5.68a 14.5 Good40 84.17±9.05a 14.5 Good32 30 45.75±7.20b 11.5 Poor35 83.83±7.14a 11.5 Good40 86.50±0.98a 11.5 GoodMeans with different superscripts are significantly different (p<0.05).Table 1. Hatching rate (means±s.d., n= 3) of Penaeus semisulcatus eggs incubated in dif-ferent salinity and temperature regimes.127also obtained the highest hatching rate at33°C and 35 ppt, followed by 29°C and 35 ppt,in F. merguiensis. In the study by Preston(1985), both low (20 ppt) and high (40 ppt)salinities had a negative impact on hatching inP. plebejus, M. macleayi and M. bennettae.On the other hand, Browdy and Samocha(1985) and Aktas and Kumlu (1999) reportedthat P. semisulcatus eggs incubated at 40 ppthad good hatching success, as demonstratedin the present study. Development of F. indi-cus and P. semisulcatus eggs was retarded at20-25 ppt and eggs swelled to the point ofbursting at 10-15 ppt (Tseng and Cheng,1981, cited in Primavera, 1985). In addition,these researchers pointed out that F. indicuseggs had a significantly higher hatching rateand shorter incubation period at 33 ppt than at22 ppt or 42 ppt. Our results and those report-ed in the literature indicate that the optimalegg incubation salinity for P. semisulcatus isabout 40 ppt. Kumlu et al. (1999b and 2000)also reported this level of salinity as optimalfor larviculture of this species. Spawning and larval stages of mostpenaeid shrimp species occur in full strengthsea water (>35 ppt) and at stable water tem-peratures. Hence, poorer hatching rates arenormally expected in salinities lower thanoceanic salinities. In the present study, 30 pptsalinity at all temperatures resulted in lowerhatching rates and poorer larval activity afterhatching. The best hatching success wasachieved at the higher salinities of 35 and 40ppt, regardless of the temperature. Similarly,among various temperature and salinity com-binations, the highest mean hatching rate forP. monodon was obtained at 33 ppt and 23-33°C, whereas 23 and 28 ppt at any tempera-ture produced weak larvae (Reyes 1981, citedin Primavera, 1985). Incubation time was mainly affected by tem-perature in the present study, as suggested forP. plebejus, Metapenaeus macleayi and M.bennettae by Preston (1985). Hatching ratepeaked between 19 and 24°C for P. plebejusand between 24 and 29°C for M. macleayi. Theoptimal temperature for hatching M. bennettaeeggs was significantly affected by the conditionsthat existed at spawning (Lester and Pante,1992). Yet, despite being spawned at 28°C, thehatching success of P. semisulcatus eggs wassimilar at all temperatures in the current study.Regardless of the salinity levels tested in ourstudy, hatching occurred in 17.5 h at 24°C,while this duration was lower at 28°C and lowerstill at 32°C. Similar findings were reported forP. monodon, i.e., increasing the temperaturefrom 23 to 33°C significantly decreased theincubation period (Primavera, 1985). The results of the present study demon-strate that eggs of P. semisulcatus obtainedfrom eastern Mediterranean broodstockshould be incubated at 35-40 ppt and 24-32°C.AcknowledgementsWe would like to thank the personnel atYumurtalık Marine Research Station for theirhelp during the study. This study is financedby the Cukurova University Research Fund,project number SUF2002BAP14.ReferencesAktas M. and M. Kumlu, 1999. Gonadal mat-uration and spawning of Penaeus semisulca-tus. Turkish J. Zool., 23:61-65.Browdy C. L. and T.M. Samocha, 1985. Theeffect of eyestalk ablation on spawning, molt-ing and mating of Penaeus semisulcatus DeHaan. Aquaculture, 49:19-29. Hillier A.G., 1984. Artificial conditions influ-encing the maturation and spawning ofsubadult Penaeus monodon (Fabricius).Aquaculture, 36:179-184.Kumlu M., Bausta N., Avar D. and O.T.Eroldoan, 1999a. Some biological aspects ofpenaeid shrimps in Yumurtalık Bight of north-eastern Mediterranean. Turkish J. Zool., 23:53-59.Kumlu M., Eroldogan O.T. and M. Aktas,1999b. The effect of salinity on larval growth,survival and development of Penaeus semi-sulcatus (Decapoda: Penaeidae). Israeli J.Aquacult. - Bamidgeh, 51(3):114-121.Kumlu M., Eroldogan O.T. and M. Aktas,2000. Effects of temperature and salinity onlarval growth, survival and development ofPenaeus semisulcatus. Aquaculture, 188:167-173.Effects of temperature and salinity on egg hatching in Penaeus semisulcatusKumlu M., Eroldoan O.T., Aktas M. and B.Salamtimur, 2001. Larval growth, survival anddevelopment of Metapenaeus monoceros(Decapoda: Penaeidae) cultured in differentsalinities. Aquacult. Res., 32:81-86.Lester L.J. and M.J.R. Pante, 1992. Penaeidtemperature and salinity responses. pp. 515-535. In: A.W. Fast, L.J. Lester (eds.). MarineShrimp Culture: Principle and Practices.Elseiver Sci. Publ. B.V., USA. Nisa Z. and M. Ahmed, 2000. Hatching andlarval survival of important penaeid shrimps ofPakistan in different salinities. Pakistan J.Zool., 32(2):139-143. Preston N., 1985. The effects of temperatureand salinity on survival and growth of larvalPenaeus plebejus, Metapenaeus macleayiand M. bennettae. pp. 31-40. In: P.C.Rothlisberg, B.J. Hill, D.J. Staples (eds.). 2ndAustralian Natl. Prawn Seminar, NPS2.Cleveland, Australia, Primavera J.H., 1985. A review of maturationand reproduction in closed thelycumPenaeids. pp. 47-64. In: Y. Taki, J.H.Primavera, J.A. Llobrera (eds.). Proc. 1st Int.Conf. Culture of Penaeid Prawns/Shrimps,December 4-7,1984, Iloilo City, Philippines. Zacharia S. and V.S. Kakati, 2004. Optimalsalinity and temperature for early develop-mental stages of Penaeus merguiensis Deman. Aquaculture, 232:373-382.128 Aktas et al.

Combined Effects Of Temperature And Salinity On Egg Hatching Rate And Incubation Time Of Penaeus Semisulcatus (Decapoda: Penaeidae)

WOS: 000222602300005This study was undertaken to determine the combined effects of temperature and salinity on the incubation time and hatching rate of Penaeus semisulcatus eggs in controlled laboratory conditions. Fertilized eggs, from a female caught in nature and spawned in our laboratory, were stocked in 2-1 round bottom glass flasks and received one of nine temperature (24, 28 and 32degreesC) and salinity (30, 35 and 40 ppt) combinations. The eggs hatched in all treatments. The hatching rate increased as salinity increased and was highest at 24degreesC. In terms of hatching rate, the best combinations in descending order were 24degreesC at 40 ppt, 32degreesC at 40 ppt and 28degreesC at 40 ppt. However, the incubation time was longer at 24degreesC (17.5 h) than at 28degreesC (14.5 h) or 32degreesC (11.5 h)

Aktas, M

Eroldogan, OT

Kumlu, M

Çukurova University Institutional Repository

Combined effects of temperature and salinity on egg hatching rate and incubation time of Penaeus semisulcatus (Decapoda : Penaeidae)

http://evols.library.manoa.hawaii.edu/bitstream/10524/19101/1/56_2_Aktas.pdf

Combined Effects Of Temperature And Salinity On Egg Hatching Rate And Incubation Time Of Penaeus Semisulcatus (Decapoda: Penaeidae)

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