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Öğe Aspects of the biology of Liza abu (Mugilidae) in the Tigris River (Turkey)(Soc Francaise D Ichtyologie, 2000) Ünlü, E; Balci, K; Meric, NSex distribution, growth in length and weight, relative condition index, attainment of first maturity age, and fecundity of Liza abu were examined in the Tigris River, South-eastern Anatolia. This species migrates towards upstream the Tigris River at a period extending from August to late February. The age of 480 specimens (263 females and 217 males) ranged between 1+ and 4+. The observed sex ratio was 1.21 female: 1 male in the studied samples. Allometric growth patterns was proved from the length-weight relationships. The female had high L infinity (204.27 mm), but low K (0.304531) value whereas the Lm (195.77 mm) for male were lower, but the K (0.383129) value was higher. It was seen that relative condition index values from August and September were higher than those recorded at other times of the year. Spawning do not occur at this time in this area. According to development of gonad, male and female become sexually mature at the first year of their life-span. The smallest mature female was 117 mm in fork length and 17 g in total weight, while male was 115 mm in fork length and 14 g in total weight. The number of oocytes ranged from 12,175 to 56,400. Fecundity was significantly correlated with fish length, fish weight and gonad weight.Öğe Concentrations of some heavy metals in water, sediment and fish species from the Ataturk Dam Lake (Euphrates), Turkey(Pergamon-Elsevier Science Ltd, 2000) Karadede, H; Ünlü, EConcentrations of heavy metals (Cd, Co, Cu, Fe, Hg, Mn, Mo, Ni, Pb and Zn) were measured in the water, sediment and fish species (Acanthobrama marmid, Chalcalburnus mossulensis, Chondrostoma regium, Carasobarbus luteus, Capoetta trutta and Cyprinus carpio) from the Ataturk Dam Lake, Turkey. Among the heavy metals studied Cd, Co, Hg, Mo and Ph were not detected in water, sediments and fish samples, while Ni was undetectable levels in fish samples. Levels of Cu, Fe, Mn and Zn varied depending on different tissues. The results of this study indicated that a general absence of serious pollution in the dam lake is due to heavy metals, where as the concentrations of elements found could mainly be attributed to geological sources. (C) 2000 Elsevier Science Ltd. All rights reserved.Öğe The effects of endosulfan on the great ramshorn snail Planorbarius corneus (Gastropoda, Pulmonata)(Pergamon-Elsevier Science Ltd, 2004) Otludil, B; Cengiz, EI; Yildirim, MZ; Ünver, Ö; Ünlü, EIn this study the great ramshorn snail (Planorbarius corneus), one of the most abundant gastropod of Turkish limnic systems, was investigated to determine the histopathological effects of endosulfan on the digestive gland, foot and mantle under laboratory conditions. Samples were collected from small artificial pools in Karaot at Gelendost-Isparta (Southwest of Turkey), where agricultural activities are widespread. The snails were exposed to two sublethal concentrations of endosulfan (0.4 and 0.8 mg/l) for periods of 10, 20 and 30 days. Fifteen snails were kept in 2.5 1 glass jars containing dechlorinated tap water and exposed under semi-static test (daily exchange of test water). All the testing was carried out on adult specimens, and snails were maintained on a photothermal period with 16 light hours at 22+/-2 degreesC. The histopathological examinations revealed the following changes: amoebocytes infiltration, dilatation in hemo-lymphatic spaces between the tubules, degeneration of cells, abnormal lumen, necrosis of cells and atrophy in the connective tissue of digestive gland; desquamation of the epithelium cells, changes in the number of mucocytes and protein gland cells, lipid vacuolus and atrophy of the columnar muscle fibers of the foot and mantle tissues. Pycnotic state of cells was also seen in the mantle tissues. Endosulfan caused significant histopathological alterations in the digestive gland, foot and mantle tissues of the snail, irrespective of concentrations of the pesticide and its exposure periods. The results are discussed, particularly in comparison to those of other aquatic organisms. (C) 2004 Elsevier Ltd. All rights reserved.Öğe The effects of the different concentrations of Thiodan® on the mortality rates of Gambusia affinis and Gammarus pulex.(Mbr Press Inc, 1999) Cengiz, EI; Ünlü, EIn this study, the acute toxicity of thiodan(R) on Gambusia affinis (Cyprinidontidae: Pisces) and Gammarus pulex (Amphiopoda: Crustacea) have been examined. In acute toxicity tests, the LC,, values at 24, 48, 72 and 96 hours were investigated for Gammarus Pulex exposed to Thiodan(R) concentrations of 0.00 (control), 0.25, 0.5, 0.75, 1.0, 2.0, 5.0, 7.5, 10.0, 15.0, 20.0, 25.0, 30.0, 35.0, 50.0, 100.0 mu/lt. The 24, 48, 72 and 96 hours LC50 values were determined as 10.641, 8.755, 4.544 and 3.248 mu/lt, respectively. Moreover, LC50 values at 24, 48, 72 and 96 hours were investigated for Gambusia affinis exposed to Thiodan(R) concentrations of 0.00 (control), 0.50, 1.00, 1.50, 2.00, 2.50, 3.00, 5.00, 10.00, 12.5, 15.0, 17.5, 20.0, 30.0, 50.0, 100.0 dir. The 24, 48, 72 and 96 hours LC50 values were determined as 14.415, 12.077, 10.035 and 6.116 mu/lt, respectively.Öğe Heavy metals in mullet, Liza abu, and catfish, Silurus triostegus, from the Ataturk Dam Lake (Euphrates), Turkey(Pergamon-Elsevier Science Ltd, 2004) Karadede, H; Oymak, SA; Ünlü, EThe distribution of some heavy metals in three different organs of mullet, Liza abu, and catfish, Silurus triostegus, from Ataturk Dam Lake located on Euphrates (Turkey) was studied. Co and Mo concentrations were below limits of detection in all fish organs, whereas Ni was also below limits in organs of mullet. The metal accumulation in the liver and gill of L. abu and S. triostegus was found to be quite high in comparison with the muscle. In general, the concentrations are similar to those previously observed on other fish studied in Ataturk Dam Lake and lower than those determined in Tigris River. The analysed metals (Co, Cu, Fe, Mn, Mo, Ni and Zn) were found in fish muscle at mean concentrations under the permissible limits proposed by FAO. (C) 2003 Elsevier Ltd. All rights reserved.Öğe Histopathological changes in the gills of mosquitofish, Gambusia affinis exposed to Endosulfan(Springer-Verlag, 2002) Cengiz, EI; Ünlü, E[Abstract Not Available]Öğe The histopathological effects of Thiodan® on the liver and gut of mosquitofish, Gambusia affinis(Marcel Dekker Inc, 2001) Cengiz, EI; Ünlü, E; Balci, KThiodan (R) (33.7% endosulfan), a polychlorinated cyclodiene insecticide, was evaluated for its histopathological effects on mosquitofish, Gambusia affinis, by light microscopy. Fish were exposed to doses of 0.00 (control), 1.00, 2.50, and 5.00 mug/L on days 7, 14, 21, and 30. No histopathological effects were apparent at control group. The histopathological alterations were characterized as oedema, degeneration, accumulation of lymphocytes in the lamina propria, disintegration of villuses, pycnotic state of nuclei, and necrosis in gut; degeneration, hypertrophy, sinusoids enlargement, hemorrhage, pycnosis position of nuclei, vacuolization of cell cytoplasm, infiltration of mononuclear lymphocyte, and congestion in liver. These alterations were time- and dose-dependent.Öğe Histopathology of gills in mosquitorish, Gambusia affinis after long-term exposure to sublethal concentrations of malathion(Marcel Dekker Inc, 2003) Cengiz, EI; Ünlü, EThe histopathological effects of malathion, an organophosphate pesticide, on the gill tissues in mosquitofish, Gambusia affinis, were determined by light microscope. The fish were exposed to sublethal concentrations (0.01 and 0.02 mg/L) of malathion for 10, 20 and 30 days. Histological examination of the gills treated with malathion showed a variety of histopathological effects. The gill lesions included necrosis and desquamation of secondary lamellar epithelium, lifting up of epithelium, intraepithelial oedema, fusion of adjacent secondary lamellae, haemorrhage at primary lamellae, disorganization and rupture in seconder lamellae, hypertrophy and hyperplasia of epithelial cells. These alterations were time- and dose-dependent.Öğe Karyotype of the cyprinid fish Alburnoides bipunctatus (Cyprinidae) from the Tigris River(Polish Acad Sciences, Inst Systematics Evolution Animals, 2004) Kilic-Demirok, N; Ünlü, EChromosome numbers and karyotypes of Cyprinid fish Alburnoides bipunctatus (Bloch, 1782)from the River Tigris were determined by the chromosome preparation technique from uncultured kidney cells. The diploid chromosome number 2n=50, was composed of 8 pairs of metacentric, 11 pairs of submetacentric and 6 pairs of subtelo-acrocentric chromosomes (NF=88). Sex chromosomes were not determined in the this species. The results were briefly discussed with other, previously conducted studies.Öğe Origin, radiation, dispersion and allopatric hybridization in the chub Leuciscus cephalus(Royal Soc, 2000) Durand, JD; Ünlü, E; Doadrio, I; Pipoyan, S; Templeton, ARTho phylogenetic relationships of 492 chub (Leuriscus cephalus) belonging to 89 Populations across the species' range were assessed using 600 base pairs of cytochrome b. Furthermore, nine species belonging to the L. cephalus complex were also analysed (over the whole cytochrome b) in order to lest potential allopatric hybridization with L. cephalus sensu stricto (i.e. the chub). Our results show that the chub includes four highly divergent lineages descending from a quick radiation that took place three million years ago. The geographical distribution of these lineages and results of the nested clade analysis indicated that the chub may have originated from Mesopotamia. Chub radiation probably occurred during an important vicariant event such as the isolation of numerous Turkish river systems, a consequence of the uplift of the Anatolian Plateau (formerly covered by a broad inland lake). Dispersion of these lineages arose from the changes in the European hydrographic network and, thus, the chub and endemic species of the L. cephalus complex met by secondary contacts. Our results show several patterns of introgression, fr om Leuciscus lepidus fully introgressed by chub mitochondrial DNA to Leuciscus borythenicus where no introgression at all was detected. We assume that these hybridization events might constitute an important evolutionary process for the settlement of the chub in new environments in the Mediterranean area.Öğe Phylogeny and biogeography of the family Cyprinidae in the Middle East inferred from cytochrome b DNA -: Evolutionary significance of this region (vol 22, pg 91, 2002)(Academic Press Inc Elsevier Science, 2002) Durand, JD; Tsigenopoulos, CS; Ünlü, E; Berrebi, P[Abstract Not Available]Öğe Rapid radiation of the Mediterranean Luciobarbus species (Cyprinidae) after the Messinian salinity crisis of the Mediterranean Sea, inferred from mitochondrial phylogenetic analysis(Blackwell Publishing Ltd, 2003) Tsigenopoulos, CS; Durand, JD; Ünlü, E; Berrebi, PPhylogenetic relationships of 64 freshwater Barbus s.s. species distributed in basins around the Mediterranean Sea were assessed using cytochrome b sequences. Our results are in concordance with previous morphological and genetic studies, which proposed that these species belong to two major lineages (or subgenera): Barbus and Luciobarbus. We were particularly interested in phylogenetic relationships among species of the Luciobarbus lineage that are primarily found in the southern Mediterranean region from the Iberian Peninsula to the Middle East. In the Luciobarbus lineage, species that were previously attributed to the Copoeta genus were clustered. In this study, we observed short internodes between monophyletic groups having a geographical agreement around the Mediterranean. However, groups from the opposite sides of the Mediterranean Sea (Iberian Peninsula-Capoeta, north-western Africa-Middle East) seem to be phylogenetically close. We therefore infer that rapid radiation of Luciobarbus species in the Late Miocene better fits our data rather than gradual founder events in the southern Mediterranean. We propose that the biogeographical event along an east-west route, responsible for the present distribution of Luciobarbus species, was the 'Lago Mare' phase of the Mediterranean Sea that provided a rapid dispersal route over extensive distances. This provides new insights into the speciation pattern of this group, and may be of general use in the study of freshwater species in these regions. (C) 2003 The Linnean Society of London.
