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Öğe Effect of Sediment Grain Size on Growth Performance of Juvenile Sea Cucumber (Holothuria tubulosa)(Central Fisheries Research Inst, 2015) Tolon, Tolga; Emiroglu, Dilek; Gunay, Deniz; Saygi, HulyaIt is important to know the impact of sediment type on feeding and growth performance of sea cucumbers in aquaculture which is getting more importance due to the critical decrease in valuable stocks in all seas. The purpose of the present study is to investigate the effect of grain size on growth performance of juvenile sea cucumber (Holothuria tubulosa) under aquaculture conditions. In the present study, the growth performance of juvenile sea cucumber (H. tubulosa) on 3 different grain sized sediment has been investigated in laboratory conditions for 61 days. Sea cucumber juveniles (35.02 +/- 0.52 g) were placed into the 200x50x50 cm aquaria by 350 g m(-2). Natural crushed quartz sediment in different grain sizes (1 mm, 3 mm, 7mm and 0.2 mm (control)) were placed inaquariaby 10cm height. Final mean weight of the juveniles in sediment groups1 mm, 3 mm, 7 mm and 0.2 mm (control) were recorded as 49.18 +/- 0.94 g, 44.23 +/- 0.35 g, 40.72 +/- 0.53 gand 39.57 +/- 0.50 g, respectively. Specific growth rate of juveniles among sediment groups were ranged between 0.20% day(-1) (Control) and 0.53 % day(-1) (1mm). Overall, best growth performance was found as significant in 1 mm sediment group.Öğe Effect of stocking density on growth performance of juvenile sea cucumber Holothuria tubulosa (Gmelin, 1788)(Wiley, 2017) Tolon, Tolga; Emiroglu, Dilek; Gunay, Deniz; Hanci, BegumStock density is one among the most important factors in aquaculture that directly influences the growth of organisms; however, there is limited information about the effects of stocking density on growth performance of sea cucumber Holothuria tubulosa (Gmelin, 1788) that has a commercial potential and represents a new species for aquaculture. In this study, we investigated the effect of stocking densities on the growth performance of juvenile H. tubulosa (40.3 +/- 3.34g) in laboratory conditions. Stocking densities were selected as 6, 15 and 30indm(-2) with total biomass 253.3 +/- 0.18, 601.2 +/- 0.11 and 1201.4 +/- 0.15g m(-2) respectively. We monitored the growth by wet weights and calculated the growth performance through weight gain, growth rate, specific growth rate, relative weight gain, coefficients of variation and survival rate during 8weeks of research period. We found that individual mean weight gain in 6indm(-2) group was approximately 29.53g while it was 3.03g and -4.36g for 15ind and 30ind m(-2) groups respectively. Results have shown that the specific growth rate tends to decrease as the number of individuals in unit area increases. The final mean weight, growth rate, specific growth rate, relative weight gain and coefficients of variation were significantly different among treatment groups. In conclusion, a density of 6indm(-2) is recommended for stocking juvenile H.tubulosa under rearing conditions. Stocking density of 15indm(-2) is not favourable for long term as the growth rate is negligible where 30indm(-2) should be avoided in tank-based rearing units.Öğe Effects of various stocking densities on hatching and survival rates of sea cucumber Holothuria tubulosa eggs (Gmelin, 1788)(Ege Univ, Fac Fisheries, 2018) Gunay, Deniz; Tolon, Mustafa Tolga; Emiroglu, DilekIn this study, it was aimed to determine the opening and survival rates of Holothuria tubulosa eggs at four different stocking densities (15,1530 eggs / ml) and to determine the effect of stocking density on egg size and larval size in different stages. Fertilized Holothuria tubulosa eggs were stocked in cylindrical conical collectors with a capacity of 30 I. Eggs were counted under light microscope at fertilization, early gastrulation, late gastrulation and hatching stages. It was found that there is an inverse relationship between stock intensity and opening rate (r= -0.848; p<0.001). The lowest hatching and survival rate was determined in 30 eggs/ml group (p <0.05). However, different stocking densities did not affect the diameter of the egg in different embryological stages (p> 0.05) and the length of early auricularia larva at 65 h (p>0.05). As a result the optimal stocking density for the highest hatching and survival rates of the fertilized eggs of Holothuria tubulosa was determined as 1-5 eggs / ml.Öğe Growth and Survival Rate of Juvenile Sea Cucumbers (Holothuria tubulosa, Gmelin, 1788) at Various Temperatures(Central Fisheries Research Inst, 2015) Gunay, Deniz; Emiroglu, Dilek; Tolon, Tolga; Ozden, Osman; Saygi, HulyaThe effect of various water temperatures on growth and survival rate of juvenile sea cucumbers (Holothuria tubulosa) had been investigated in this research. Average weight of 20.48 +/- 2.33 g of juvenile sea cucumbers were collected from the coastal zones of Aegean Sea by scuba diving. After the adaptation period, juveniles were placed into glass aquaria which have 4 different sea water temperatures and researched for 45 days under laboratory conditions. Sea water temperatures of trial groups were selected among the minimum (winter) and maximum (summer) temperatures recorded at the natural habitat of H. tubulosa juveniles. Thus, 4 temperature group were selected as 15, 20, 25 ve 30 degrees C. The sea cucumber juveniles were fed on dried and powdered brown algae as references in the literature. The best specific growth rate (SGR) was recorded as 0.288 +/- 0.02 % day(-1) in 25 degrees C group. The lowest SGR was recorded as 0.085 +/- 0.005 % day(-1) in 30 degrees C trial group while the negative specific growth rate (-0.03 +/- 0.02 % day(-1)) was recorded in 15 degrees C trial group. The aestivation observed in 30 degrees C and hibernation in 15 degrees C group would be a reason for such lower specific growth rates. The survival rate for all groups were 100% and the best growth performance was recorded in 25 degrees C among others (P<0.05).Öğe LC-HRMS Based Approach for Identification and Quantification Analysis of Chemical Constituents of Sea Cucumbers from Aegean Sea - Their Cytotoxic and Antiviral Potentials(Acg Publications, 2022) Sarikahya, Nazli Boke; Okkali, Gaye Sumer; Gunay, Deniz; Goren, Ahmet C.; Coven, Furkan Ozan; Nalbantsoy, AyseThere are nearly 1200 species of sea cucumber in the world's seas. Among these creatures included in the Holothuroidea class, 37 species show distribution in the Mediterranean and Aegean Sea. The purpose of this study is to determine the chemical content and biological potent of five sea cucumber species, Holothuria tubulosa, Holothuria poli, Holothuria mammata, Holothuria sanctori and Stichopus regalis which were collected from the Aegean Sea. The detailed flavonoid, phenolic and triterpene contents were determined by LCHR/MS. Cytotoxic activities against several cancer cell lines, MDA-MB-231, PC-3, A549, PANC-1, HEPG2 and a healthy cell line CCD-34LU were performed by MTT method. Antiviral activities of the samples were measured as virucidal activity against avian coronavirus by in ovo. According to the results of LC-HRMS analysis, H. sanctori, H. poli and S. regalis had the richest chemical content diversity in terms of examined triterpene compounds. Fumaric acid was detected as the most abundant substance in all sea cucumber species. H. tubulosa had a highly toxic effect on all the tested cells. The best cytotoxic activity on A549 cells was seen in H. mammata, H. sanctori and H. poli. H. sanctori also showed a significant toxic effect against PANC-1, MDA-MB-231, HepG2 and A549 cells, whereas the IC50 value in CCD-34LU cells was above 50 mu g/mL for this sample. The n-butanol extracts of sea cucumber species reduced hemagglutination (HA) virus titer between 1-fold to 4-fold in log2-based at all tested concentrations. The best inhibited virus HA titer results were found in H. tubulosa at 5 mu g/g. According to these results we have obtained, the extracts of sea cucumbers may be used in many fields such as medicine, food, cosmetics in the future. This study is also very important in terms of being a guide for all studies on the use, processing and production of sea cucumbers and detailed isolation and purification studies on sea cucumber species from Turkey.Öğe Reproductive cycle of the temperate sea cucumber Holothuria tubulosa in the northeastern Aegean Sea(Wiley, 2024) Engin, Serhat; Tolon, Mustafa Tolga; Gunay, Deniz; Emiroglu, DilekObjective: The aim of this study was to determine the reproductive cycle and spawning frequency of the sea cucumber Holothuria tubulosa in the northeastern Aegean Sea. Methods: The study covered a period of 12 months, beginning in October 2018 and concluding in September 2019. During this period, sea cucumber samples were collected monthly. Macroscopic and histological examinations of gonadal tubules were conducted to provide credible information for fishery management and aquaculture. Result: The sex ratio of the sampled population was 1:1.3, with 95 males and 130 females. The drained body weights at 50% maturity were 70.90 g for females and 70.80 g for males. The total length at 50% maturity was estimated at 18.58 cm for females and 18.05 cm for males. Gonad maturation was initiated in March and progressed to spawning stages between July and August. From September to February, the gonads were in postspawning and recovery stages. A strong linear correlation was determined between the gonad index and the seawater temperature in the area. Conclusion: The information provided is expected to improve stock management, enforce fishery regulations, and support controlled breeding programs. These measures aim to preserve the natural populations of Holothuria tubulosa and guarantee the long-term viability of the species in the wild.Öğe Sea cucumber (Holothuria tubulosa Gmelin, 1790) culture under marine fish net cages for potential use in integrated multi-trophic aquaculture (IMTA)(Natl Inst Science Communication-Niscair, 2017) Tolon, Mustafa Tolga; Emiroglu, Dilek; Gunay, Deniz; Ozgul, AytacIn this study, integrated aquaculture of Mediterranean sea cucumber species Holothuria tubulosa under finfish net cages was investigated. To evaluate whether H.tubulosa can be reared under net cage farms without additional feed and to compare growth performances, three underwater ranches (10x10m), just below a net cage (A), between the net cages (B) and 750 m away from the net cage systems (K) were set. Fifty sea cucumbers (92.81 +/- 2.29 g) were placed into each research station and growth performances like specific growth rate (SGR) and weight gain were observed for 90 days. SGR of sea cucumbers in stations A, B and K were 0.3 +/- 0.04, 0.22 +/- 0.02 and 0.10 +/- 0.01 %/d, respectively. The highest mean weight gain 31.11 +/- 0.84 g was recorded at station A where the lowest was in station K as 8.89 +/- 0.12 g. Organic carbon and organic material amount of research stations significantly affected the final mean weights of sea cucumbers where the highest growth was determined at the stations A and B. The results suggest that integrated multi-trophic aquaculture (IMTA) systems combined with finfish and sea cucumber H. tubulosa under net cages would provide by-products to aquaculture farms without an extra feed costs in the Mediterranean Sea.Öğe Seasonal variations of digestive enzymes in sea cucumbers (Holothuria tubulosa, G. 1788) under culture conditions(Wiley, 2020) Gunay, Deniz; Emiroglu, Dilek; Suzer, CuneytSea cucumber, Holothuria tubulosa (Gmelin, 1788), is an economically valuable species due to its rich nutrients content that being exported in Turkey. However, culture of this species is difficult due to a lack of knowledge. the main objective of this study is to investigate seasonal activities of main digestive enzymes (protease, lipase, and amylase) for nutritional requirements. in this sense, sea cucumbers were stocked in the glass aquarium and sediment was 10 cm. It was replaced monthly and enriched (1% of the living individual weight) by dried Sargassum sp. Total protease and amylase enzymes have shown higher activity compared to lipase. All three enzyme activities were maximum in the summer and minimum in the winter. in summer, the highest measured total protease, amylase, and lipase activity values were 6.45 +/- 0.66, 6.77 +/- 0.72, and 2.78 +/- 0.32 U/mg per protein, respectively. in winter, the lowest total protease, amylase, and lipase activity values were measured as 2.03 +/- 0.16, 1.14 +/- 0.14, and 0.12 +/- 0.01 U/mg per protein, respectively. As a conclusion of the study, seasonal expression of the main digestive enzymes was strictly dependent on water temperatures and food abundance and also it was ideal to feed this species with food containing high protein and carbohydrate under appropriate temperatures for commercial culture.
