Yazar "Agdamar, Sevan" seçeneğine göre listele

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    Beneficial effects of Oral Allspice, Pimenta dioica powder supplementation on the hemato-immunological and serum biochemical responses of Oreochromis mossambicus
    (Wiley, 2016) Gullu, Kenan; Acar, Umit; Kesbic, Osman Sabri; Yılmaz, Sevdan; Agdamar, Sevan; Ergün, Sebahattin; Turker, Ali
    The present study investigated the effects of dietary allspice powder supplementation on welfare status of Tilapia, Oreochromis mossambicus assessed by hemato-immunological and serum biochemical parameters. Five diets were formulated to contain 0 (control), 5, 10, 15 or 20g of allspicekg(-1) of fish feed. Fish were fed experimental diets for 60days. Supplementation of allspice powder at 10gkg(-1) positively influenced the serum glucose, plasma lysozyme activity and myeloperoxidase activity. Dietary allspice powder at 15gkg(-1) also positively influenced the serum biochemical parameters (total protein, albumin and globulin) and plasma lysozyme activity. However, 20gkg(-1) allspice powder group had significantly lower values of respiratory burst activity and red blood cell count than other experimental groups (P<0.05). In conclusion, the results of the present study demonstrated that supplementation of allspice powder at 10 or 15gkg(-1) for 60days, had beneficial effects on improvement of some immunological and serum biochemical status of O. mossambicus. These findings suggest that dietary supplementation of allspice powder might further improve the resistance to fish pathogens.
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    Genetic differentiation of non-native populations of Gibel Carp,Carassius gibelioin Western Turkey by ISSR and SRAP markers
    (Taylor & Francis Ltd, 2020) Agdamar, Sevan; Baysal, Omur; Yildiz, Aysegul; Tarkan, Ali Serhan
    Freshwater fish are one of the most frequently translocated and introduced aquatic animal groups and exhibit higher establishment ratios than many other taxa. Introductions are usually irreversible. One of common non-native fish species in Turkey is the Gibel Carp,Carassius gibeliowhich was introduced in the 1980s and is now widespread. We tested dominant markers (ISSR and SRAP) for genetic characterisation of Gibel Carp samples collected from eight locations in western Turkey. ISSR and SRAP marker sets showed that the level of gene flow between these populations (N-m= 0.45 /N-m= 0.47) is low and that the level of genetic differentiation (G(ST)= 0.53 /G(ST)= 0.52) is high. Inter-population variation detected by ISSR and SRAP markers constituted half part of the population (46.88 / 50.00%), while the rest was at intra-population level. These results indicate that the present population of the Gibel Carp is the result of several colonization events originating from the different sources. The phylogenetic relationship among the populations suggest that there were two independent major introduction events, one in the Marmara Region and the other in southern Turkey.
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    High genetic diversity in an invasive freshwater fish species, Carassius gibelio, suggests establishment success at the frontier between native and invasive ranges
    (Elsevier Gmbh, 2019) Agdamar, Sevan; Tarkan, Ali Serhan
    Non-native freshwater fish introductions can have direct and indirect negative effects on native flora and fauna, ecosystems, and national economies. Although invasions are paradoxical from an evolutionary standpoint, population genetics could be useful to understand invasion scenarios of non-native species. One of the most common introduced fish in Europe and Turkey is the gibel carp Carassius gibelio, which was first introduced from East Asia in the 17th century. To find out the origin and distribution pattern and characterise the genetic variation of gibel carp in Turkey, the aim of this study was to identify haplotype the species' diversity and distribution in the country. Three mitochondrial (COI, Cyt-b and D-loop) and one nuclear (ITS1) DNA markers were used in 20 populations sampled from 18 different geographic locations, resulting in eight newly-identified haplotypes. The present results: (i) suggest high genetic diversity across regions at both the mitochondrial (29 haplotypes, h = 0.9058, pi = 0.0152) and nuclear (3 haplotypes, h = 0.6365, pi = 0.0094) level; (ii) confirm previous findings that this species may have entered Turkey directly either from its native or through its invasive range; (iii) suggest that, given the distribution of the identified haplotypes by geographic location, the majority of individuals not only originated from the northern (European) part of Turkey but also from the southern (Mediterranean) part of the country. Understanding the genetic characterisation of gibel carp can contribute to more efficient management actions for this species, including prevention of (multiple) introductions and eradication/control of those populations with relatively low genetic diversity. (C) 2019 Elsevier GmbH. All rights reserved.
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    Life in Extreme Conditions: Diet and Condition of the Extremophile Fish Aphanius almiriensis (Teleostei: Cyprinodontiformes) in a Thermal Rheocrene Spring
    (Wiley, 2025) Sac, Gulsah; Ozulug, Oya; Agdamar, Sevan; Inci, Harun; Yurekli, Ozgun Deniz; Ozulug, Mufit
    This study aims to understand the bioecological traits of an extremophile fish, Aphanius almiriensis, in order to explore how it survives and colonizes extreme habitat conditions. To achieve this, the bioecological characteristics-condition, diet, and feeding strategy-of A. almiriensis inhabiting the Tuzla thermal spring, which is characterized by extreme habitat conditions in terms of physicochemical water parameters, were studied. Among the physicochemical parameters measured, salinity and temperature were remarkably high, ranging from 23.7 degrees C (in winter) to 42.7 degrees C (in summer) and from 47.7 ppt (in autumn) to 60.7 ppt (in winter). A total of 248 fish individuals were collected from the thermal spring, and the diet analyzed seasonally consisted of 17 different food items, and their importance values (MI% and IRI%) varied seasonally. According to the F%, IRI%, and MI% values, the population fed mainly on Diatom, Cyanobacteria, and Diptera, resulting in niche breadth with low values ranging from 0.25 to 0.54. The extreme conditions of the thermal spring indicated that the environment was poor in terms of macroinvertebrate diversity (six taxa), and fish showed food selectivity (E) for Chironomidae and Ceratopogonidae in winter, spring, and summer and for Ephydridae in autumn (E > 0; positive selectivity). Seasonally influenced fish condition was represented by high values in summer (K = 1.43 +/- 0.14) and was positively correlated with both water temperature and the increasing importance of the genus Phormidium in its diet. This study provides the first comprehensive insight into the seasonal diet and condition of A. almiriensis, shedding light on its survival strategies in harsh ecological conditions.
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    Low Genetic and Parasite Diversity of Invasive Pumpkinseed Lepomis gibbosus (Centrarchidae) Expanding in Turkiye
    (Mdpi, 2024) Kvach, Yuriy; Tkachenko, Maria Yu.; Giannetto, Daniela; Mic, Robert; Bartakova, Veronika; Agdamar, Sevan; Sac, Gulsah
    Multiple factors can facilitate invasion success, with the absence of natural enemies, such as predators and parasites, recognised as conferring a significant advantage on invasive over native species. Pumpkinseed Lepomis gibbosus (Centrarchidae) represents one of the most successful freshwater fish invaders in Europe. Previous research has highlighted genetic differences between pumpkinseed populations in T & uuml;rkiye and those in other European regions, attributed to rapid adaptation to new environmental conditions. This study aimed to investigate whether these highly adapted pumpkinseed populations in T & uuml;rkiye benefit from a potential release from parasites, as proposed by the enemy-release hypothesis. Genetic characterisation of pumpkinseed populations from both European and Asian parts of T & uuml;rkiye revealed that they share the same cytochrome c oxidase I haplotype as European populations. Microsatellite analysis indicated low genetic diversity, with STRUCTURE analysis confirming the clustering of all Turkish populations, suggesting a common source. Consistent with the low genetic diversity indicative of a small founding population, we observed a limited number of co-introduced parasite species, including the myxozoan Myxobolus dechtiari, the monogenean Onchocleidus dispar, and the digenean Posthodiplostomum centrarchi. Parasite infection by local parasites acquired in T & uuml;rkiye was rare. Parasite diversity, species richness, and equitability were low, with only nine parasite taxa identified in all four pumpkinseed populations. The most diverse parasite community was found in De & gbreve;irmenk & ouml;y Reservoir, located in the European part of T & uuml;rkiye, where seven parasite taxa were identified. While our study did not uncover genetically distinct pumpkinseed populations in T & uuml;rkiye, the fish demonstrated resilience against most local parasite species, potentially providing them with an advantage over native species, aligning with the enemy-release hypothesis.
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    Population Genetic Structure of Petroleuciscus borysthenicus (Kessler 1859) in Northwestern Türkiye Using Mitochondrial COX1 Gene
    (Wiley, 2024) Agdamar, Sevan; Sac, Gulsah; Acar, Umit; Gaygusuz, Ozcan; Dogac, Ersin; Ozulug, Mufit
    Petroleuciscus borysthenicus is a species with a wide distribution from the eastern, western, and northern Black Sea and Azov Sea basins, the Aegean Sea basin, and Northwestern T & uuml;rkiye. However, there has been relatively little attention on the genetic variability of this species in their native distribution range, and nearly no study has been conducted in T & uuml;rkiye despite its importance in biodiversity. The aim of this study was to elucidate the genetic variability and population structure of P. borysthenicus from Northwestern T & uuml;rkiye using an integrated molecular method. A total of 72 specimens were collected from 13 localities in the Northwestern part of T & uuml;rkiye. A total of six haplotypes were identified in all specimens. A relatively low level of genetic variability was found for P. borysthenicus throughout the study region based on the indices of genetic diversity including haplotype diversity and nucleotide diversity for the cytochrome oxidase subunit I (h = 0.507, pi = 0.0027). The pairwise FST values between the samples ranged from -0.123 to 1.000. Furthermore, our results revealed no provable recent demographic expansion for P. borysthenicus from Northwestern T & uuml;rkiye. However, more studies using additional geographic sampling and molecular analysis are needed to enhance our knowledge of the diversity and distribution of this species.
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    Seasonal and Spatial Variation in the Diet of Gambusia holbrooki in Different Water Bodies of Karaburun Peninsula (Western Türkiye)
    (MDPI, 2025) Sac, Gulsah; Agdamar, Sevan; Acar, Umit; Giannetto, Daniela
    The Eastern mosquitofish Gambusia holbrooki Girard, 1859, has been widely introduced into tropical and temperate countries as a biological agent to control mosquitos, which are associated with diseases such as malaria and yellow fever. However, the species exhibits invasive characteristics by competing with native species for food and habitat use. This study investigates the feeding ecology of G. holbrooki populations from three distinct freshwater environments (Lake Iris, E & gbreve;lenhoca Reservoir, and Parlak Reservoir) on the Karaburun Peninsula (North-Western T & uuml;rkiye), a region outside its native range. The primary aim was to evaluate seasonal and spatial variations in the diet of the species. A total of 871 specimens were analysed: 247 from Iris Lake, 318 from Parlak Reservoir, and 306 from E & gbreve;lenhoca Reservoir. Low percentages of empty stomachs (<= 20%) across all populations indicate high feeding intensity. The results reveal that G. holbrooki exhibits a generalist feeding strategy, consuming a wide range of food items such as insects, zooplankton, and plant material across all the investigated environments. The relative importance of food groups (determined by the Importance Index, MI%) varied seasonally but not spatially. In all three populations, the most important food source in the spring was dipterans, followed by plants in the summer and fall, and cladocerans in the winter. Plants accounted for the largest percentage of the diet in every population (MI% >65%). These findings suggest that G. holbrooki adapts its diet to seasonal food availability.