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Öğe Levels of infection and seasonal occurrence of Gyrodactylus alviga (Monogenea: Gyrodactylidae) on the whiting Merlangius merlangus off the Turkish and Russian coasts of the Black Sea(Cambridge Univ Press, 2016) Ozer, A.; Kornyychuk, Y.; Ozturk, T.; Yurakhno, V.Gyrodactylus alviga is a generalist species reported in many Black Sea fish species, but whiting is known to be its main host. It is the only monogenean parasite that has been reported so far on the skin, fins and gills of whiting Merlangius merlangus in the Black Sea. A total of 690 fish from Turkey and 423 fish from Russia were examined to detect parasites. Infection indices of prevalence, mean intensity and mean abundance values were calculated for length classes and sex of fish, as well as for the seasons. There is a gradual increase in infection indices in relation with increasing host length classes and there are higher infection indices on female fish. Furthermore, despite lower prevalence indices in spring and winter, higher parasite intensity values were determined in these seasons. It is concluded that larger fish provided more space and food for G. alviga, and female fish were more parasitized as they were more active in searching for food, which enables the parasite to switch between hosts. In addition, winter and spring were more appropriate for reproduction of G. alviga.Öğe Molecular characterization and morphological aspects of Myxobolus parvus (Myxozoa) from Liza saliens (Mugilidae) off the Turkish Black Sea coasts(Springer, 2016) Ozer, A.; Gurkanli, C. T.; Ozkan, H.; Acar, G.; Ciftci, Y.; Yurakhno, V.Members of the phylum Myxozoa are among the most cosmopolitan parasites of fish, and the genus Myxobolus is the largest within the class Myxosporea in freshwater and marine environment from all over the world. Myxobolus parvus has been reported from mainly mugilid fishes from different localities including the Black Sea. Leaping mullet Liza saliens collected by fishermen off Sinop coasts of the Black Sea in the period between September 2014 and December 2015 was investigated for myxosporean parasites using conventional methods. M. parvus Schulman, 1962 was the only Myxobolus species identified and it was found in the gills, gall bladder, kidney tubules, and inside several cysts located on the lower jaw of examined fish in the present study. Morphometric data and all details of parasitic infection were determined and presented in tables and illustrated in figures. Molecular characterization was also conducted to reveal its position within Myxosporea. Two M. parvus samples from gills and kidney showed the same haplotype and appeared in the same sub-lineage with marine Myxobolus species. The closest haplotypes to M. parvus were Triactinomyxon sp. and Endocapsa sp. which are the actinosporeans forms of unknown myxozoan species. These data are the first in molecular characterization of M. parvus, its occurrence in lower jaw of leaping mullet along with its infection prevalence values off the Turkish Black Sea coasts.Öğe Morphological and molecular descriptions ofSphaeromyxa sevastopoli(Cnidaria) from host fishes from Sinop on the Black Sea coast(Springer, 2020) Okkay, S.; Gurkanli, C. T.; Ciftci, Y.; Yurakhno, V.; Ozer, A.Members of the genusSphaeromyxaThelohan, 1892 have been reported from a wide variety of fish species worldwide. In the present study, specimens of rusty blenny,Parablennius sanguinolentus, collected from Sinop on the Turkish Black Sea coast were investigated for myxosporean parasites by using both conventional and molecular methods.Sphaeromyxa sevastopoliNaidenova1970was the only myxosporean parasite found in the gall bladder of host fishes. The morphology peculiarities of obtainedS. sevastopolispores are in good agreement with those of original description and the morphometric data overlapped in spore length and width but differed in polar capsule length and width; however, they were within the ranges previously reported from 18 host fish species. Moreover, in the present study, molecular analysis of the 18S rDNA gene ofS. sevastopoliisolate in ourP. sanguinolentusas well as isolates from shore rocklingGaidropsarus mediterraneusand knout gobyMesogobius batrachocephaluswhich were previously morphologically identified and reported by Okkay and ozer (Acta Zool Bulg 72(1):123-130,2020) was done for the first time and our threeS. sevastopoligenotypes were allocated to the balbianii group which is characterized by straight or slightly curved and fusiform or ovoid spores with ovoid polar capsules.Öğe Morphology and molecular phylogeny of Ortholinea mullusi sp nov (Myxozoa) in Mullus barbatus from the Black Sea(Inter-Research, 2018) Gurkanli, C. T.; Okkay, S.; Ciftci, Y.; Yurakhno, V.; Ozer, A.Myxosporeans of the genus Ortholinea have a worldwide distribution and infect organs and tissues of exclusively marine fishes. Here we describe the morphological and molecular characteristics of Ortholinea mullusi sp. nov. parasitizing the urinary bladder and kidney tubules of red mullet Mullus barbatus collected from the coastal zone of Sinop in the Black Sea, Turkey. Polysporic plasmodia with immature spores were either elongate, 37.0 +/- 4.5 SD (30-50) mu m long and 45.0 +/- 3.8 (40-55) mu m wide, or were round, up to 100.0 mu m in diameter. Mature, free spores were spherical in the frontal view and measured 9.3 +/- 0.2 (9.0-9.7) mu m in length, 8.7 +/- 0.3 (8.2-9.3) mu m in width and 7.7 +/- 0.1 (7.5-7.9) mu m in thickness. We observed 2 polar capsules of equal size, which measured 3.1 +/- 0.1 (3.0-3.2) mu m long by 2.5 +/- 0.1 (2.4-2.6) mu m wide, and the tips of the polar capsules were open towards the sutural line. The prevalence of infection by O. mullusi sp. nov. was 24.5%. Phylogenetic analysis based on nuclear small subunit ribosomal DNA (SSU rDNA) clearly suggested O. mullusi to be a new species, clustered within a lineage comprising O. labracis and O auratae. Pairwise nucleotide similarities and DNA distance values between O. mullusi sp. nov. and sister Ortholinea species also supported this suggestion.Öğe Morphology, histology and phylogeny of Henneguya sinova sp nov (Myxobolidae: Myxozoa) infecting gills of Parablennius tentacularis in the Black Sea, Turkey(Inter-Research, 2016) Ozer, A.; Ozkan, H.; Gurkanli, C. T.; Yurakhno, V.; Ciftci, Y.Myxosporeans of the genus Henneguya have a global distribution and infect organs and tissues of both marine and freshwater fishes. Here we describe the morphological, histological and molecular characteristics of Henneguya sinova sp. nov. parasitizing the gill arches of tentacled blenny Parablennius tentacularis (Perciformes: Blenniidae) collected from the coast of Sinop on the Black Sea in Turkey. Several oval whitish plasmodia of different sizes in the gill arches of fish were found. The mature spores were rounded oval in frontal view, with a mean (range) total length 57.5 (51.5-68.0) mu m; the spore body was 11.7 (11.3-12.0) mu m in length by 7.6 (7.3-8.3) mu m in width and 6.7 (6.6-6.8) mu m in thickness. The caudal appendages, measuring 46.0 (40.0-55.0) mu m in length, were very thin at the tapered end. The prevalence of infection by H. sinova sp. nov. was 35.5%. Phylo genetic analysis of nuclear small subunit ribosomal DNA (SSU rDNA) clearly suggested H. sinova as a new species which is clustered within the marine Henneguya lineage. Pairwise nucleotide similarities and DNA distance values of SSU rDNA between H. sinova sp. nov. and other related Henneguya species also supported this suggestion.Öğe Myxosporean parasites of Ceratomyxa merlangi and Myxidium gadi in whiting Merlangius merlangus: a comparative epizootiological analysis based on samples from two localities off southern and northern coasts of the Black Sea(Springer, 2017) Ozer, A.; Yurakhno, V.; Ozturk, T.; Kornyychuk, Y. M.Totally 690 and 423 whiting Merlangius merlangus samples were collected from two localities off Southern (Sinop) and Northern coasts (Balaklava Bay) of the Black Sea, respectively, and examined for myxosporeans in the period from May 2011 to March 2014. Ceratomyxa merlangi and Myxidium gadi were the only myxosporean parasites identified in the content of gall bladder and their infection indices of prevalence (%) and intensity were calculated for length classes and sex of fish as well as for the seasons at both sampling localities. Overall infection prevalence of C. merlangi was 22.6% in Sinop and 27.9% in Balaklava samples while those values of M. gadi were 18.4% and 28.6% in Sinop and Balaklava samples, respectively. Both parasite species were also found to be co-existed in whiting samples. This is the first comprehensive epizootiological study yielded comparable data on C. merlangi and M. gadi infections in whiting in the southern and northern coasts of the Black Sea.Öğe Parasite fauna of garfish Belone belone collected from Sinop coasts of the Black Sea, Turkey(Eur Assoc Fish Pathologists, 2013) Ozer, A.; Yurakhno, V.Parasite fauna of garfish Belone belone was determined in 16 fish specimens collected from Turkish coasts of the Black Sea in January and February 2013. A total of 6 parasite species was identified:Ceratomyxa beloneae, Sigmomyxa sphaerica, Axine.belones, Hysterothylacium aduncum, Diphyllobothrium sp. procercoids and Trichodina sp. Their morphometric measurements, infection prevalences, intensities and their sites of infection were presented. C. beloneae and S. sphaerica are new parasite records for Turkey and A. belones, H. aduncum, Trichodina sp. and Diphyllobothrium sp. are reported in B. belone in Turkish coasts of the Black Sea for the first time.Öğe Seasonality and host-parasite interrelationship of Hysterothylacium aduncum (Nematoda) in whiting Merlangius merlangus off the southern and northern coasts of the Black Sea(Walter De Gruyter Gmbh, 2016) Ozer, A.; Kornyychuk, Y. M.; Yurakhno, V.; Ozturk, T.In the present study, we investigated the comparative infection levels, ecology and host-parasite interrelationship of a nematode Hysterothylacium aduncum (Rudolphi, 1802) in whiting, Merlangius merlangus (L., 1758) in southern (Sinop) and northern (Balaklava Bay) coasts of the Black Sea for the first time. Fish were collected throughout a period from May 2011 to March 2014 from local fishermen. A total of 690 fish specimens near Sinop and 423 fish near Balaklava Bay were examined for parasites. Hysterothylacium aduncum was the only nematode species identified in the digestive tract of the Black Sea whiting Merlangius merlangus. Prevalence of infection, mean intensity and mean abundance values were determined according to season, length classes and sex of fish at both localities. These infection indices were always higher in Sinop samples than those of Balaklava Bay samples.
