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Öğe A skeletochronological analysis of a population of the Anatolia Newt, Neurergus strauchii (Steindachner, 1887) (Caudata: Salamandridae), in Eastern Anatolia, Turkey(Taylor & Francis Ltd, 2015) Yakin, Batuhan Yaman; Cicek, Kerim; Koyun, Mustafa; Gurkan, Mert; Hayretdag, Sibel; Tok, Cemal VarolThis study presents data on age, growth and longevity of a population of Neurergus strauchii in Eastern Anatolia (Bingol, Turkey) based on skeletochronological data. The phalangeal diaphyseal cross-sections of 54 individuals studied (12o, 42f) showed that females are on average older than males: the ages ranged from 6 to 14 years, with an average age of 8.8 years in males and 10.9 years in females. Sexual maturity is reached at an age of 4-5 years in both sexes. The slow growth and the longevity make the species vulnerable.Öğe Acute toxic effects of cadmium in larvae of the green toad, Pseudepidalea variabilis (Pallas, 1769) (Amphibia: Anura)(Inst Medical Research & Occupational Health, 2014) Gurkan, Mert; Cetin, Ayse; Hayretdag, SibelThe environmental impact of cadmium use and its accumulation in nature have increased to alarming levels. This study aimed to morphologically and histologically investigate the acute toxic effects of cadmium on green toad, Pseudepidalea variabilis (Pallas, 1769) larvae. Embryos were obtained from specimens collected in amplexus from nature and kept under laboratory conditions until stage 26, when they were exposed to cadmium (0, 1, 5, 10, 25, and 50 mu g L-1) for 96 h. The LC10, LC50, and LC90 values of cadmium were calculated to be 26.98, 35.35, and 46.31 mu g L-1, respectively. Our results showed that cadmium had a negative effect on the body size of P. variabilis larvae (over 1 mu g L-1). Histological examination detected a fusion of gill lamellae, liver haemorrhage, oedema in the abdominal cavity, and deformations of pronephric tubules (over 10 mu g L-1). Our findings suggest that the green toad was sensitive to the cadmium treatment, with LC50 values lower than those reported by other studies. Thus, this species could be considered a reliable indicator species of environmental stress in aquatic ecosystem.Öğe Acute toxicity of maneb in the tadpoles of common and green toad(Inst Medical Research & Occupational Health, 2015) Gurkan, Mert; Hayretdag, SibelPesticides used in agriculture can have hazardous effects on aquatic organisms, and amphibians are even more threatened than other aquatic vertebrates. Maneb is widely used to control fungal diseases on crops, fruits, and vegetables. The aim of this study was to investigate the acute toxic effects of maneb on the common (Bufo bufo) and green toad (Pseudepidalea viridis) tadpoles. Tadpoles at the development stage 21 were exposed to maneb (0-5 mg L-1) for 120 h. Maneb LC50 values at hour 120 were 1.966 mg L-1 for B. bufo and 0.332 mg L-1 for P. viridis. To the best of our knowledge, these are the first published LC50 findings for the two species. Visceral oedema and tail deformations were observed in both species. We also observed liver necrosis, pronephric tubule deformations, somite deteriorations, and visceral oedema at maneb concentrations >= 0.1 mg L-1 for B. bufo and >= 0.05 mg L-1 for P. viridis. Our results show that B. bufo tadpoles have a much higher resilience to maneb than P. viridis tadpoles. This resilience seems to be related to the larger size of the B. bufo tadpoles and their ability to metamorphose faster in adverse conditions. Future research should look into the mechanisms of toxic action of maneb in anurans.Öğe Data on the Food Composition of European Glass Lizard, Pseudopus apodus (Pallas, 1775) (Squamata: Anguidae) from Canakkale (Western Anatolia, Turkey)(Inst Zoology, Bas, 2014) Cicek, Kerim; Tok, Cemal Varol; Hayretdag, Sibel; Ayaz, DincerWe examined the food composition of the European Glass Lizard, Pseudopus apodus, from canakkale (Western Anatolia, Turkey), by means of the stomach content analysis. Some 72 prey items with sizes ranging from 10 to 60 mm were detected in the stomach contents of the 13 (7 male male, 6 female female) museum specimens under examination. The median number of prey items was 5 (range = 3-8) in males and 4 (4-6) in females. According to the obtained data, the class Insecta (86.1%) is the predominant food of the species, with the most frequently observed prey items belonging to the order Coleoptera (76.4%). Orthoptera (4.2%), Hemiptera (5.6%), Gastropoda (8.3%), and Isopoda (5.6%) are the other prey groups observed in the food contents. Even though no difference in food contents was observed between the sexes, the food niche breadth of females was higher. In conclusion, the main food of P. apodus consists of non-flying or weak-flying insects as well as other invertebrates.Öğe Embryonic and larval development of black skirt tetra (Gymnocorymbus ternetzi, Boulenger, 1895) under laboratory conditions(Wiley, 2012) Celik, Ihsan; Celik, Pinar; Cirik, Sukran; Gurkan, Mert; Hayretdag, SibelThe embryonic and larval development of black skirt tetra, Gymnocorymbus ternetzi, are described under controlled laboratory conditions. In addition, major histomorphological changes and the allometric growth patterns during larval development have been described. The laboratory-reared broodstock, that is 1 similar to year of age, were spawned. Hatching occurred 2021 similar to h after spawning at 24 +/- 0.5 degrees C. The cleavage was finished in 2 similar to h and the early blastula stage occurred at 2:04 hours after spawning. The gastrulation started at 3:20 similar to hours and 30% epiboly was observed at 3:34 similar to hours after spawning. Eight-somite stage was observed at 08:33 hours. And embryonic developmental stage was completed at 21 similar to h after spawning. The newly hatched larvae were 1442 +/- 14.3 similar to mu m in mean total length (TL). The mouth opened at 3 days after hatching (DAH). The yolk sac had been totally absorbed and the larvae started to swim actively within 34 similar to days. Notochord flexion began at 11 DAH. The metamorphosis was completed and the larvae transformed into juveniles at 32 DAH. In this paper, the full developmental sequence from egg to juvenile of G. ternetzi is described for the first time.Öğe Genetic structuring of Anguis fragilis (L., 1758) inhabiting in the north of 40° north latitude in Turkey(Taylor & Francis Ltd, 2013) Keskin, Emre; Hayretdag, Sibel; Cicek, Kerim; Ayaz, Dincer; Tok, Cemal VarolThe taxonomic situation of Anguis fragilis species is still unclear in Turkey. In order to clarify this situation, we used the DNA sequences of 16S rRNA and cytochrome b genes to analyze the phylogenetic relationship among A. fragilis populations. A total of 13 haplotypes in 16S rRNA dataset and 20 haplotypes in cytochrome b dataset were detected. Kimura 2-parameter genetic distance was found to be 0.012 for 16S rRNA and 0.026 for the cytochrome b dataset. Neighbor joining (NJ) trees were constructed to analyze phylogenetic relationship among specimens and were supported with median joining networks. Results indicate a clear genetic structuring in A. fragilis populations sampled from north of 408 north latitude of Turkey. Both mitochondrial gene sequences successfully detected the intraspecific variation among specimens of different populations. Genetic structuring, correlated with geographic distance, was found to be significant at the specimens sampled from edge populations of peripherally isolated climatic conditions.Öğe Genetic structuring of Pseudopus apodus (Pallas, 1775) (Sauria: Anguidae) in north Anatolia, Turkey(Pergamon-Elsevier Science Ltd, 2013) Keskin, Emre; Tok, Cemal Varol; Hayretdag, Sibel; Cicek, Kerim; Ayaz, DincerIn this study, mitochondrial 16S rRNA and cytochrome b sequences were used to infer the genetic structure of Pseudopus apodus (Pallas, 1775) populations sampled from 40 North latitude of Turkey. Mean percent G-C contents of 47.13 and 46.66 were determined for 16S rRNA and cytochrome b datasets, respectively. Two haplotypes were found using 16S rRNA dataset, with 6 variable loci and a haplotype diversity of 0.1053, while Cytochrome b dataset consist of 10 haplotypes, with 18 variable loci and a haplotype diversity of 0.1943. Also mean genetic distance was found to be eight times higher in the cytochrome b dataset. Kimura 2-parameter genetic distance matrix was evaluated together with neighbor joining tree and median joining network in order to reveal possible divergence points in both datasets. Results indicated signs of 3 regional populations, including potential cryptic species from Digor or subspecies from Samsun and Sinop. (C) 2013 Elsevier Ltd. All rights reserved.Öğe Histopathological effects of Montivipera xanthina venom on rats(Tubitak Scientific & Technological Research Council Turkey, 2012) Topyildiz, Huseyin; Hayretdag, SibelIn this study, the histopathological changes caused by Montivipera xanthina venom to rat skin, skeletal muscle, and liver tissue were analysed by light microscope. The venom (approximately 2.85 mg/kg) was injected intramuscularly into the gastrocnemius muscle of the rats. The animals were dissected 1, 3, and 6 h after the injection time, and tissue samples were taken. Sections 5 pm thick were taken from paraffin blocks of tissue samples, and the sections were stained with haematoxylin and eosin in order to facilitate examination by light microscope. Examinations showed no damage to the epidermis layer of skin. However, damage to the dermis layer, including oedema, haemorrhage, local bleeding, rare inflammatory cells, strong cell infiltration with mixed characteristics, inflammation around the veins, and fat necrosis, was detected. The damage observed in muscular tissue was myonecrosis, mixed character cell infiltration, haemorrhage, and the formation of inclusion on myofibrils. The liver tissue revealed sinusoidal congestion and hepatocellular degeneration.Öğe Investigation of the effects of pre-incubation formaldehyde fumigation on the tracheal epithelium of chicken embryos and chicks(Tubitak Scientific & Technological Research Council Turkey, 2008) Hayretdag, Sibel; Kolankaya, DuerdaneThis study aimed to evaluate the effects of pre-incubation formaldehyde fumigation on the tracheal epithelium of chicken embryos and chicks. Throughout the study pre-incubation formaldehyde fumigation was applied to 18-day-old embryos and 1-day old chicks only once, at 1 of 2 different concentrations (3 x, 42 ml of formalin and 21 g of potassium permanganate per m(3) and 4 x, 56 ml of formalin and 28 g of potassium permanganate per m3) for 1 of 2 different durations (20 min and 40 min). Tracheal samples were taken from 18-day-old embryos and 1-day-old chicks, and the tracheal epithelial cells were examined with transmission electron microscopy (TEM). According to TEM, after fumigation cilia in the epithelial cells were shorter and fewer in number, and vacuolisation, swelling of the mitochondria, and spoiling of cristae were observed in the subjects, which varied according to fumigation concentration and duration.Öğe Morphological and histological effects of copper sulfate on the larval development of green toad, Bufo viridis(Tubitak Scientific & Technological Research Council Turkey, 2012) Gurkan, Mert; Hayretdag, SibelDeclines in populations of amphibians have been occurring more dramatically over the past 25 years. The declines have various causes. One of the possible causes of amphibian declines is pesticides. Copper sulfate is commonly used as a fungicide in vineyards and gardens in Turkey. In this study, our purpose was to explain the morphologically and histologically acute toxic effects of copper sulfate on Bufo viridis tadpoles. B. viridis tadpoles at Gosner stage 21 were exposed to different concentrations (0.01, 0.05, and 0.1 mg/L) of copper sulfate for 120 h. The LC50 value of copper sulfate was calculated as 0.058 mg/L. Morphological measurements indicated that copper sulfate concentrations of 0.05 and 0.1 mg/L caused poor larval development and growth. Edema was observed in the histological sections, especially on the cross-sections passing from the head (>= 0.01 mg/L CuSO4). Furthermore, hepatocellular degeneration in the liver, deformation of gastrointestinal epithelial cells, and deformation and anomalies in somite formations were all observed (>= 0.01 mg/L CuSO4). Reduced reaction to stimuli, loss of equilibrium, and shortening of swimming distance were observed in the tadpoles of the 0.05 and 0.1 mg/L CuSO4 treatment groups.Öğe Range extension and morphology of the Italian wall lizard, Podarcis siculus (Rafinesque-Schmaltz, 1810) (Squamata: Lacertidae), from Turkey(Tubitak Scientific & Technological Research Council Turkey, 2015) Tok, Cemal Varol; Cicek, Kerim; Hayretdag, Sibel; Tayhan, Yahya; Yakin, Batuhan YamanA record of the Italian wall lizard, Podarcis siculus (Rafinesque-Schmaltz, 1810), from Atakum (Samsun, Central Black Sea Region) is provided in this study. In addition, 5 specimens (3 male male and 2 female female) from Atakum (Samsun) and 14 specimens (7 male male and 7 female female) from Gelibolu (Canakkale, Thrace), with records provided recently, were evaluated in terms of measurements, pholidosis, and color and pattern. With the record from Samsun, the Italian wall lizard's distributional range has been extended about 360 km eastwards. The specimens examined from both localities were determined to resemble P. s. hieroglyphicus (Berthold, 1840), distributed in Thrace and Anatolia. Moreover, some information on the breeding biology of the specimens is provided.Öğe The effect of pollen on serum parameters of rats(Elsevier Ireland Ltd, 2006) Selmanoglu, Guldeniz; Hayretdag, Sibel; Kolankaya, Durdane; Tuylu, Asli Ozkok; Sorkun, Kadriye[Anstract Not Available]Öğe The effect of pollen on some reproductive parameters of male rats(Elsevier Ireland Ltd, 2007) Selmanoglu, Gueldeniz; Hayretdag, Sibel; Kolankaya, Durdane; Tueylue, Asli Ozkoek; Sorkun, Kadriye[Anstract Not Available]Öğe The effect of Trifolium, Raphanus, and Cistus pollen grains on some blood parameters and mesentery mast cells(Walter De Gruyter Gmbh, 2006) Kolankaya, Durdane; Senturk, Hakan; Tuylu, Asli Ozkok; Hayretdag, Sibel; Selmanoglu, Guldeniz; Sorkun, KadriyeThree kinds of pollen taxa belonging to 3 families (Fabaceae - Trifolium spp., Brassicaceae - Raphanus spp. and Cistaceae - Cistus spp.) and commonly collected by honeybees were fed to mature male rats separately, in the form of 60 mg/animal/day for a 30-day period. The objective of this study was to investigate any positive effects or possible side effects of the use of pollen on the immune system. This was achieved through blood analysis and cell count on blood, hemoglobin, erythrocyte and immune system cells. The cell concentration of mast cells, degranulization and cell localization were investigated in prepared mesentery tissue samples. Histological investigations of the stomach and duedenum sections of pollen-fed rats were carried out to learn the reason for eosinophil gastroenteritis in the alimentary canal. The eosinophil and lymphocyte levels of rats fed with pollen of Trifolium spp., Raphanus spp., and Cistus spp. were observed to have increased blood cell counts, while neutrophil and monocyte levels decreased; different values were found in basophil leucocytes between the pollen groups. Differing reductions in mesentery mast cell concentration, degranulization and cell localization were found. Within the three separate pollens, the rats having been fed with Cistus spp. pollen were observed to have higher blood lymphocyte, eosinophil, hemoglobin and hematocrit values than those fed with the others, as well as low mesentery mast cell concentration. Hemoglobin values were determined to increase at a proportion of between 10.0-11.3%. No difference was found in other blood parameters. The fat proportion of the male rats fed with the three taxa was between 4.03-8.75%, while that for protein proportion was between 16.11-24.25%. Male rats receiving these taxa did not experience allergic reactions and it is possible to argue that the low protein and fat content of these pollens have a strengthening effect on the immune systems by the increase in lymphocyte content and the amount of hemoglobin leads to an increase of oxygen transport capacity in the tissues.Öğe The effects of Macrovipera lebetina venom on mice(Taylor & Francis Inc, 2019) Agan, Aydan Fulden Yucel; Hayretdag, SibelThe aim of this study is to reveal the effects Macrovipera lebetina venom - one of the two most venomous (the other one is Montivipera xanthina) snake species in Turkey - histopathologically on liver, kidney and heart tissues of mice. The venom was injected into the tail veins of male mice at three different doses (0.5, 1 and 1.5 mg kg(-1)). The animals were dissected 2 h after the injection, and their liver, kidney and heart tissues were examined histologically by light microscopy. Results of histopathological examination showed, degeneration, mononuclear cell infiltration, vacuoles around the nuclei and sinuzoidal congestion in livers; cellular degeneration, deformation in the structure of the glomerulus, intertubular congestion and mononuclear cell infiltration in the kidneys; and vacuoles around the nucleus, necrosis, congestion and mononuclear cell infiltration in heart tissues.
