Hydroxylated-Benz[a]anthracenes Induce Two Apoptosis-Related Gene Expressions in the Liver of the Nibbler Fish .

Polycyclic aromatic hydrocarbons (PAHs) are known to have toxic effects on fish. In this study, we examined the effects of benz[a]anthracene (BaA), a type of PAH, on fish liver metabolism. Nibbler fish () were intraperitoneally injected with BaA (10 ng/g body weight) four times over a 10-day period.

Lernaea cf. cyprinacea infection in agile frog (Rana dalmatina) tadpoles in Hungary.

The ectoparasitic copepod Lernaea cyprinacea (anchor worm) has more than 100 host species among teleost fishes and affects cyprinids both in fish farms and natural waters. In addition, while L. cyprinacea infection in amphibians has been recorded in Asia, North and South America, there is no data available in the literature on their presence in Europe.

Assessing phenotypic variation and plasticity of endemic gastropods from thermal water refugia using complex morphometric techniques: A case study of Lake Pețea melanopsids.

Understanding the underlying reasons for phenotypic plasticity and resulting morphological disparity is one of the key topics of evolutionary research. The phenotypic plasticity of extant and fossil melanopsids has been widely documented. Yet millennial-resolution, well-dated records from small aquatic habitats harboring endemics are scarce.

Removal of dead fish eggs by Asellus aquaticus as a potential biological control in aquaculture.

The objective of the present experimental study was to gain a better understanding of the foraging activity of Asellus aquaticus during fish egg incubation. A. aquaticus were introduced into experimental setups of dead eggs, viable eggs and hatched larvae of zebrafish (Danio rerio), a commonly used model organism.

Uncommon life history and winter spawning of common carp (Cyprinus carpio) in a natural thermal spring, under temperate climate.

Common carp female generally matures at age 4-5 years old and spawns between April and July under the temperate climate. Contrary to a range of 0-28 °C of temperate freshwaters, the water temperature of Lake Hévíz (Hungary, Central Europe), the largest natural bathable thermal lake in the world, varies between 26 and 35 °C seasonally. The specific environmental conditions (continuously warm water and its individual chemical composition, special nutrient base, lack of natural lakeside spawning substrate compared to usual spawning grounds, continuous high human disturbance, etc.

Review of Central-Eastern European Propagation and Larvae Nursing Method for Common Carp ( L.).

Common carp ( L.) as a cultivated fish species has huge importance all over the world. According to FAO statistics, carp is the third most widely bred freshwater pond fish species; only two other Cyprinids (silver carp and grass carp) are bred in higher amounts.

Physiological Response of Grower African Catfish to Dietary Black Soldier Fly and Mealworm Meal.

A six-week experiment was carried out to test the effects of total (100%) and partial (50%) replacement of fish meal in the diet of African catfish growers with black soldier fly (B) meal, yellow mealworm (M) meal, and a 1:1 combination of both (BM) on the production and health of fish. A total of 420 fish with an average initial body weight of 200 ± 0.5 g were randomly distributed in triplicate to seven diet groups (C, B50, B100, M50, M100, BM50, and BM100, respectively).

Carp Breeding in the Carpathian Basin with a Sustainable Utilization of Renewable Natural Resources.

In the Central European region, there is a long tradition of breeding fish in artificially constructed ponds. As the area belongs to the temperate zone, farmed fish need to survive cold winter periods. Common carp ( L.

Ovarian inseminated sperm impacts spawning success in zebrafish, Danio rerio (Hamilton, 1822) even in the absence of a male stimulus.

Reproductive obstacles have led scientists to develop novel techniques/technologies for artificial reproduction. We aimed to investigate the possibility of propagating zebrafish females using sperm ovarian lavage with and without presence of male stimulus. This experiment consisted of several treatments: traditional spawning approaches with females and wild-type males (AB♀ × AB♂); no males present with non-manipulated females (AB♀); no males present with females inseminated with NaCl into ovarian lobes [AB♀(inj.

Changes in Cadmium Concentration in Muscles, Ovaries, and Eggs of Silver European Eel () during Maturation under Controlled Conditions.

This study determined the contents of cadmium (Cd) in the muscles, ovaries, and eggs of silver female European eels. The analysis of cadmium content was performed on female European eels caught during commercial fishing in freshwater in Warmia and Mazury (Poland), and then subjected to artificial maturation and ovulation processing under controlled conditions. The content of cadmium (Cd) in the tissues was determined by flameless atomic spectrometry using an electrothermal atomizer.

A novel strategy for conservation of European eel (Anguilla anguilla) genetic resources: Cryopreservation of ovarian stem cells.

The aim of this study was to develop short- and long-term preservation protocols for European eel ovarian stem cells (OSCs) through hypothermic storage and cryopreservation of ovarian fragments that will assist in current conservation programs of this critically endangered species. Firstly, a freezing procedure was developed by testing different cryomedia and technical aspects of freezing. Utilization of 1.

Development and characterization of 49 novel microsatellite markers in the African catfish, Clarias gariepinus (Burchell, 1822).

The African catfish or sharp tooth catfish (Clarias gariepinus) is one of the important species (due to its high environmental tolerance and easily controllable breeding habits) that can significantly contribute to reducing hunger in many countries. It is farmed in numerous African, Asian, and European countries. Moreover, during the last decades its production has grown significantly worldwide.

Eel sperm cryopreservation: An overview.

The eels are teleost fishes from the order Anguilliformes that includes several species with high commercial value. Due to the high interest for aquaculture production of some eel species and for the need to restore eel species that are endangered, several research groups have directed their research toward developing protocols to cryopreserve the spermatozoa of Japanese eel (Anguilla japonica) and European eel (Anguilla anguilla). In this review, we provide an overview on the different protocols that have been developed so far.

Artificial insemination of African catfish (Clarias gariepinus) using cryopreserved sperm.

In this study, we aimed to develop a practical protocol for using cryopreserved sperm for induced/wild/tank spawning of fish species with external fertilization. Experiments were carried out on African catfish (Clarias gariepinus) as a model species. Sperm was collected for cryopreservation and diluted with the cryomedium (266 mM fructose, 20% methanol) at a ratio of 1:1 with a final methanol concentration of 2.

Testing cryopreserved European eel sperm for hybridization (A. japonica × A. anguilla).

The objective of this study was to assess impact of cryopreserved European eel sperm and Japanese eel native sperm on early fertilization, hatch, survival, and malformation rates of larvae, as well as develop molecular techniques to distinguish different eel species. Eggs from Japanese eel females (Anguilla japonica) were artificially fertilized with sperm of Japanese eel males and cryopreserved sperm from European eel (A. anguilla, extender was modified Tanaka solution and methanol as cryoprotectant).

Fusiform vateritic inclusions observed in European eel (Anguilla anguilla L.) sagittae.

Microscopic inclusions have been observed in 7 out of 106 European eel (Anguilla anguilla L.) sagittae using polarizing microscope and scanning electron microscope meanwhile the annual increments were studied to characterize the age structure of the population living in Lake Balaton. The presence of vaterite, a rare calcium carbonate polymorph was observed in these inclusions using Raman spectroscopy.

Species-specific markers provide molecular genetic evidence for natural introgression of bullhead catfishes in Hungary.

Since three bullhead catfish species were introduced to Europe in the late 19th century, they have spread to most European countries. In Hungary, the brown bullhead () was more widespread in the 1970s-1980s, but the black bullhead () has gradually supplanted since their second introduction in 1980. The introgressive hybridization of the two species has been presumed based on morphological examinations, but it has not previously been supported by genetic evidence.

Full genome sequence of a novel circo-like virus detected in an adult European eel Anguilla anguilla showing signs of cauliflower disease.

An adult European eel Anguilla anguilla, showing typical signs of the so-called cauliflower disease, was subjected to pathological and molecular virological examinations. Samples taken from internal organs and the polypoid proliferative tissue from the mouth were examined by PCR for the detection of several viruses. Positive results were obtained with a nested PCR targeting the rep gene of circoviruses.

Re-visiting phylogenetic and taxonomic relationships in the genus Saga (Insecta: Orthoptera).

Twelve of the 13 bushcricket species of the Saga genus are bisexuals and diploids, except the parthenogenetic and tetraploid bush cricket, Saga pedo. Despite a continuous research effort stretching through the 1900s, the taxonomic relationships of the Saga species are still disputed. In this study, our primary aim was to reveal natural relationships of the European Saga species and three of their Asian relatives, with special attention to the problematic taxonomy of two subspecies: S.

Intraovarian transplantation of stage I-II follicles results in viable zebrafish embryos.

Maternal gene products drive early embryogenesis almost exclusively until the mid blastula transition (MBT) in many animal models including fish. However, the maternal contribution to embryogenesis does not stop at MBT, but continues to be an essential regulator of key developmental processes. The extent to which maternal effects contribute to embryonic and larval development is hard to estimate due to the technical difficulty of interfering with maternal gene products by conventional forward and reverse genetic tools.