Fish helminths in reservoirs of the Zarafshan river

The results of the study of the helminth fauna of 8 species fish of the lower reaches reservoirs of the Zarafshan River are presented - carp (Cyprinus carpio), crucian carp (Carassius auratus gibelio), roach (Rutilus rutilus), oriental bream (Abramis brama), pike perch (Stizostedion lucioperca), silver carp (Hypophthalmichthys molitrix), pike (Esox lucius), Turkestan barbel (Barbus capito conocephalus). 27 species of helminths were identified, including 12 species of cestodes (Caryophyllaeus laticeps Pallas, 1781; Caryophyllaeus fimbriceps Annenkova - Chlopina, 1919; Biacetabulum appendiculatum Szidat, 1937; Khawia sinensis Hsu, 1935; Bathybothrium rectangulum Bloch, 1782; Bothriocephalus opsariichthydis Yamaguti, 1934; Ligula intestinalis Linnaeus, 1758 larvae; Digramma interupta Rudolphi, 1810 larvae; Proteocephalus torulosus Batsch, 1786; Neogryporhynchus cheilanoristrotus Wedl, 1855 larvae; Gryporhynchus pusillus von Nordman, 1832 larvae; Valipora campylancristrota Rudolphi, 1819 larvae), 5 species of trematodes (Sanguinicola inermis Plehn, 1905; Orientocreadium siluri Bychowsky et Dubinina, 1954; Allocreadium isoporum Looss, 1894; Diplostomum spathaceum Rudolvae, 1832 lare; (Dioctophyme renale Goeze, 1782 larvae; Rhabdochona denudata Dujardin, 1845; Desmidocercella numidica Seurat, 1920 larvae; Camallanus truncatus Rudolphi, 1814; Camallanus lacustris Zoega, 1776; Philometra ovatachenko Zeder, 1803; 1779 larvae) and 2 species of acanthocephalus (Pomphorhynchus laevis Muller, 1776; Acantocephalus lucii Muller, 1776). This work includes the results of the research of the helminthes of the fish of waterbodies in the lowers of the Zarafshan River. As a result, the infection of fish with 27 species of helminthes, belonging to cestodes (12), trematodes (5), nematodes (8), and acanthocephalans (2) was established.

АНАЛИЗ ЭПИЗООТИЧЕСКОГО СОСТОЯНИЯ РЫБ ДЕЛЬТЫ ДОНА И ВОСТОЧНОЙ ЧАСТИ ТАГАНРОГСКОГО ЗАЛИВА В СОВРЕМЕННЫХ УСЛОВИЯХ, "Наука юга России"

Обобщены сведения по зараженности паразитами сельди Alosa immaculate, тарани Rutilus rutilus, судака Sander lucioperca, сазана Cyprinus carpio, карася серебряного Carassius gibelio, леща Abramis brama, бычка-сирмана Ponticola syrman, бычка-песочника Neogobius fluviatilis, бычка-кругляка N. melanostomum на основании собственных и литературных данных. Спектр паразитических организмов у рыб в дельте р. Дон и восточной части Таганрогского залива в 2019–2020 гг. включал представителей 9 классов: по 1 виду Myxrosporea, Peritricha, Bivalvia, по 3 вида Myxosporidia и Cestoda, 10 видов Monogenea, 6 видов Trematoda, 4 вида Nematoda и 5 видов Crustacea. В общей сложности у представителей азовской ихтиофауны выявлено 33 вида и не определенных до вида паразитов, из которых доминирующее положение (81 %) занимали пресноводные виды. Состав паразитов обследованных рыб отличался низким видовым разнообразием, количественные показатели – широкой вариабельностью. Выявлены потенциально патогенные для здоровья рыб виды (Myxobolus sandrae, Dactylogyrus extensus, D. vastator, Diplozoon paradoxum, Gyrodactylus sprostonae, Ancyrocephalus paradoxus, Caryophyllaeus laticeps, Khawia sinensis, Diplostomum spathaceum, Unionidae gen. sp., Achtheres percarum). Дан анализ эпизоотологической ситуации в дельте р. Дон и в восточной части Таганрогского залива и выделены возбудители, вызывающие заболевания рыб (Ligula intestinalis, Digramma interrupta), животных и человека (Apophallus donicus, Cryptocotyle concava, C. lingua, Hysterothylacium aduncum, Eustrongylides excisus).

ТРЕМАТОДОФАУНА ЧЕРЕВОНОГИХ МОЛЮСКІВ (GASTROPODA) ВЕРХІВ’Я КИЇВСЬКОГО ВОДОСХОВИЩА

Our study aimed to examine the current state of trematodes diversity in Kyiv reservoir. The molluscs under analysis belong to the species living for more than two years. The presence of trematode invasion in molluscs indicates the permanent or periodic presence of infected vertebrate hosts in area. Low mobility of the molluscs contributes to specification of the specific reservoir section visited by the definitive hosts. The species composition and quantitative indicators of invasion of the larval stages (cercariae) of trematodes (Digenea) in six species of Gastropoda in the Dnieper area of the upper site of Kyiv reservoir were studied. In total up to 490 specimens of Gastropoda belonging to subclasses Pulmonata (Lymnaea stagnalis Linnaeus, 1758, Planorbarius corneus Linnaeus, 1758, Stagnicola palustris Muller, 1774) and Prosobranchia (Fagotia acicularis Férussac, 1823, Viviparus viviparus Linnaeus, 1758, Bithynia tentaculata Linnaeus, 1758) were examined. The largest number of trematodes species was found in molluscs L. stagnalis (Lymnaeidae) and B. tentaculata (Bithyniidae) which amounted to seven and three species accordingly. The highest abundance, 150 and upper per mollusc specimen, were Diplostomum spathaceum (Rudolphi, 1819) and Tylodelphys conifer (Mehlis, 1846). Three species of trematodes were recorded in B. tentaculata − Cercaria lophocerca Filippi, 1857, Pleurogenoides medians (Olsson, 1876), Palaeorchis incognitus Szidat, 1943 with an average abundance upper 280 and prevalence 8−17%. Basically, the definitive hosts of the detected species of trematodes are fish, amphibians and waterfowl. Detected cercariae of trematodes D. spathaceum, Sanguinicola intermedia Ejsmont, 1925, Metagonimus yokogawai (Katsurada, 1912), Echinostoma revolutum (Fröhlich, 1802), Echinoparyphium recurvatum (Linstow, 1873) may cause diseases and sometimes death of fish and waterfowl. Some species may be used in medicine.

Intestinal Flukes Recovered from a Herring Gull, Larus argentatus, in the Republic of Korea

Trematode specimens were collected from the intestine of a herring gull, <i>Larus argentatus</i>, which was found in a critical condition on the shore of a small island (Yubu-do, Seocheon-gun, Chungcheongnam-do) located at the western coast of the Korean peninsula. Total 11 specimens of intestinal flukes, including 3 <i>Cryptocotyle lingua</i> (Heterophyidae), 1 <i>Himasthla alincia</i> (Echinostomatidae), 5 <i>Cardiocephaloides medioconiger</i> (Strigeidae), and 2 <i>Diplostomum spathaceum</i> (Diplostomidae), were recovered. <i>C. lingua</i> was morphologically characterized by the presence of a large ventrogenital apparatus and 2 obliquely tandem testes. <i>H. alincia</i> had an elongated body and a head collar equipped with 31 collar spines. <i>C. medioconiger</i> had a bisegmented body and a voluminous copulatory bursa containing the seminal vesicle and ejaculatory duct. <i>D. spathaceum</i> also had a bisegmented body and its vitellaria extended up to the anterior border of the tribocytic organ. It is of note that <i>C. lingua</i> is potentially zoonotic that can occur in birds and humans. Three of them, i.e., <i>C. lingua</i>, <i>C. medioconiger</i>, and <i>D. spathaceum</i>, are new trematode fauna in Korea. Studies on trematode fauna of migratory birds should be continued in Korea.

ПАРАЗИТОЦЕНОЗ СУДАКА (Sander lucioperca) КУРШСКОГО ЗАЛИВА

Паразитофауна судака водоемов Калининградской области изучалась фрагментарно, и данные о ней носят устаревший характер. Для оценки ихтиопатологического состояния рыбы необходим постоянный мониторинг изменений в составе паразитофауны и показателей зараженности. Проведены четырехлетние исследования паразитофауны судака, обитающего в российской части Куршского залива (Балтийское море). У судака обнаружено 18 видов паразитических орга-низмов: миксоспоридии Myxobolus dispar; микроспоридии Glugea luciopercae; моногенеи Ancyrocephalus paradoxus; цестоды Triaenophorus nodulosus, Diphyllo-bothrium latum; трематоды Bunocotyle cingulate, Diplostomum spathaceum, Tylodel-phys clavata, Bunodera luciopercae, Azygia lucii, Ichthyocotylurus platycephalus, I. variegatus, Bucephalus polymorphus; нематоды Raphidascaris acus, Camallanus lacustris; скребни Acanthocephalus lucii, Corynosoma strumosum; паразитические ракообразные Achtheres percarum. Полный паразитологический анализ проводился по методике, разработанной И. Е. Быховской-Павловской. В паразитоценозе судака преобладают паразиты со сложным жизненным циклом (со сменой промежуточных хозяев). Так, в 2016 г. их доля составила 76,5 % (13 видов); 2017 – 73,4 (11); 2018 –71,4 (10); 2019 – 73,4% (11 видов), тогда как с прямым циклом развития в 2016 г. было 23,5%; 2017 – 26,6; 2018 – 28,6; 2019 – 26,6% (по четыре вида в каждом исследуемом году) паразитов. Повышение зараженности судака трематодами может указывать на процессы эвтрофикации в водоеме. За четыре года исследований наблюдались значительные различия в составе паразитофауны и экстенсивности заражения отдельных видов паразитических организмов. Ос-новной путь заражения паразитами со сложным циклом развития – трофический. Представители класса трематод доминируют в паразитофауне судака Куршского залива (восемь видов). Наибольшая экстенсивность инвазии зарегистрирована у моногенеи Ancyrocephalus paradoxus (100% в 2019 г.), метацеркария трематоды Ichthyocotylurus platycephalus (100% в 2019 г.) и паразитического ракообразного Achtheres percarum (100% в 2016-2019 гг.).

A systematic review of the parasites (Plathelminthes: Trematoda) of the Wels catfish (Silurus glanis L., 1758)

The Wels catfish or sheatfish (Silurus glanis L., 1758) is one of the important commercial fishes. Its native range extends from Eastern Europe to Western Asia. Recently, the species range has expanded both to the west and south due to the introduction. In the water bodies of Azerbaijan, the Wels catfish exists at the southernmost border of its range. It was recorded from the Kura River and its basin. There is no survey of parasitological studies on the trematodes of the Wels catfish. The previous papers have not covered all systematic groups or all the areas where the fish is distributed. Based on the literature data, we prepared a systematic review of the Wels catfish trematodes within the catfish present-day range (native area plus the areas of introduction), including Azerbaijan. The list is given according to the system of parasitic organisms implemented in the Catalog of parasites of freshwater fishes of North Asia. We also took into account new studies in the trematode taxonomy. Each species is provided with the following data: synonyms, habitat in the fish body, collecting localities, geographic distribution within the catfish range, infection rates, and references. As a result, 33 trematode species were found in the Wels catfish. They belong to three orders (Aspidogastridea ‒ 1 species, Strigeida ‒ 16 species, and Plagiorchiida ‒ 16 species), 15 families and 24 genera. Of these, 14 species are distributed in the waterbodies of Azerbaijan. The family Diplostomidae (9 species) dominates among the Wels catfish’ trematode parasites. The most Wels catfish trematodes within its whole range are Bucephalus polymorphus, Orientocreadium siluri and Diplostomum spathaceum. We established that Aspidogaster limacoides, Plagioporus skrjabini, Phyllodistomum petruschewskii were recorded from Ukraine only, Allocreadium siluri and Bolboforus confusus, from Uzbekistan, and Asymphylodora kubanica, Bychowskycreadium bychowsky, Bychowskycreadium schiliani, Diplostomum mergi, Diplostomum chromatophorum, and Diplostomum paraspathaceum from Azerbaijan.

Novel luminescent dyes for confocal laser scanning microscopy used in parasite Trematoda diagnostics*

Benzanthrone derivates are now widely used in many industrial and scientific applications as a dye for polymers and textiles. In biochemical, biomedical and diagnostics investigations benzanthrone dyes are used as a lipophilic fluorescent probe as many benzanthrone derivates demonstrate bright fluorescence and they have ability to intercalate between lipids of membrane. The aim of present research was to access the luminescence ability of benzanthrone derivatives using microscopic visualization of biological objects. Accordingly, specimens of freshwater trematode Diplostomum spathaceum, Diplodiscus subclavatus and Prosotocus confusus were stained by all novel benzanthrone dyes using different fixatives. The samples were examined by confocal laser scanning microscope. All dyes showed good results of digestive and reproductive system visualization. Based on obtained results we conclude that all benzanthrone dyes could be used for internal and external structure confocal laser scanning microscopic imaging of trematode specimens.

Occurrence and intensity of parasites in goldfish (Carassius auratus L.) from Guilan province fish ponds, north Iran

In this survey 109 specimens of goldfish (Carassius auratus) were collected from Guilan fish ponds during 2012-13. After recording biometric characteristics, common parasitology methods were used. In the present study 11 parasite species were recovered from goldfish. Parasitofauna consisted of two protozoans: Ichthyophthirius multifiliis and Trichodina sp.; one digenean trematodes: Diplostomum spathaceum; six monogenean trematodes: Dactylogyrus vastator, Dactylogyrus formosus, Dactylogyrus baueri, Dactylogyrus anchoratus and Gyrodactylus sp.; one crustacean: copepodid stage of Lernaea cyprinacea and one nematodes larvae. All the monogeneans found during the current study are considered new locality records for goldfish in Guilan province, Iran. Mean intensity of infection and abundances of parasite species (with prevalences >10%) among seasons were tested by the Kruskal-Wallis test (KW, multiple comparisons) and Conover-Inman test. Results have shown that monogeneans had the highest prevalence values (49.54%) in goldfish in Guilan fish ponds.