Artificial reproduction of the indoor-cultured brackish form of maraena whitefish (Coregonus maraena) under recirculated aquaculture system (RAS) conditions.

Maraena whitefish (Coregonus maraena) is a promising coldwater aquaculture species, especially in terms of meat quality. This versatile whitefish species, which inhabits both fresh and brackish waters, including the Baltic Sea, offers promising prospects for aquaculture breeding and cultivation. However, the main problem is the lack of availability of spawners of this species.

Gonadogenesis and annual reproductive cycles of an endangered cyprinid fish, the lake minnow Eupallasella percnurus (Pallas, 1814).

In this study, gonadogenesis, the effect of temperature (15, 20 and 25°C) on sex differentiation, and annual changes in the gonads of mature lake minnow Eupallasella percnurus (Pallas, 1814) were determined. The lake minnow was found to be a primary gonochoristic fish species, where gonads are formed directly in the ovaries or testes. The morphological differentiation of gonads was initiated 35days post hatch (DPH) when two types of gonadal anlages were visible: a pear-shaped gonad attached by a single mesentery string and a spindle-shaped gonad attached on both sides to the peritoneum.

Effect of dilution in sperm maturation media and time of storage on sperm motility and fertilizing capacity of cryopreserved semen of sex-reversed female rainbow trout.

Masculinized females, also called neomales or sex-reversed females have a male phenotype but retain the female genotype (XX). Therefore, all spermatozoa produced in their functional testes carry an X chromosome, which is desired for the production of all-female rainbow trout populations. Semen of sex-reversed female rainbow trout is of low quality and in vitro maturation is required, which includes dilution of sperm suspensions with specially formulated maturation solutions.

Motility of carp spermatozoa is associated with profound changes in the sperm proteome.

Unlabelled: In freshwater cyprinids, spermatozoa are quiescent in seminal plasma and sperm motility is initiated by a decrease in osmolality (hypo-osmotic shock) after discharge into the aqueous environment. However, it is unknown at present if and to what extent changes in proteins are involved in carp sperm motility. Therefore, the aim of our study was to identify proteins related to carp sperm motility through a comparison of immobilized and activated carp spermatozoa using a 2D-DIGE approach.

Temporal Changes in Gametogenesis of the Invasive Chinese Pond Mussel Sinanodonta woodiana (Lea, 1834) (Bivalvia: Unionidae) from the Konin Lakes System (Central Poland).

Gametogenesis and the temporal changes occurring in the ovaries and testes throughout the reproductive cycle in the invasive alien bivalve, Chinese pond mussel Sinanodonta woodiana (Lea), from the heated Konin lakes system (central Poland) were studied using histological techniques. S. woodiana was confirmed to be a gonochoristic species with overall sex ratio of 1:1.

Proteomic analysis of extracellular medium of cryopreserved carp (Cyprinus carpio L.) semen.

During freezing and thawing, spermatozoa are exposed to physical and chemical stressors that result in adverse changes in sperm structures and physiological functions. The present study provides, for the first time, a comprehensive description of protein changes in the extracellular medium of cryopreserved semen. Using 2D-DIGE and a combination of protein fractionation by one-dimensional gel electrophoresis and high performance liquid chromatography electrospray ionization tandem mass spectrometry, 183 proteins released from sperm to an extracellular medium were identified.

Maturation of spermatozoa from rainbow trout (Oncorhynchus mykiss) sex-reversed females using artificial seminal plasma or glucose-methanol extender.

Masculinized females (sex-reversed females) produce only homogametic spermatozoa (X) for fertilization which is desired for the production of all-female rainbow trout populations. The milt of sex-reversed females is of low quality and must be matured through extension in maturation solutions. The aim of this study was to compare the usefulness of glucose-methanol (GM) extender with artificial seminal plasma (ASP) extender for the maturation of milt of sex-reversed female rainbow trout.

Biochemical and physiological characteristics of semen of sex-reversed female rainbow trout (Oncorhynchus mykiss, Walbaum).

This works studies the biochemical (protein concentration, osmolality, antitrypsin activity, lactate dehydrogenase activity) and physiological characteristics (sperm motility characteristics) of semen of sex-reversed female rainbow trout (n=42) obtained with the application of 11β-hydroksyandrostendione for sex reversal. All data were arbitrarily divided into three classes depending on the percentage of sperm motility: I XX<25%; II XX 25-50% and III XX>50%. The average percentage of sperm motility was 18±7% n=12 (group I XX); 42±6% n=15 (group II XX) and 65±12% n=15 for group III XX, respectively) to link the values of semen parameters to the maturation stage of semen.

Carp transferrin can protect spermatozoa against toxic effects of cadmium ions.

Cadmium is a widespread heavy metal that enters the aquatic environment and affects many processes involved in fish reproduction such as sperm motility. Fish seminal plasma proteins can protect spermatozoa against toxic effects of heavy metals. The objective of this study was to demonstrate the ability of a major carp seminal plasma protein-transferrin (TF) to bind cadmium ions and to neutralize the toxic effect of cadmium on carp sperm motility.

Exposure of rainbow trout milt to mercury and cadmium alters sperm motility parameters and reproductive success.

In the current work, seminal plasma was used for the first time as an incubation medium for monitoring short-time exposure effects of sublethal concentrations of mercury and cadmium ions on rainbow trout sperm. Sperm motility parameters (CASA) and hatching rates were used as gamete quality markers. Additionally live/dead sperm viability test and comet assay of DNA fragmentation were performed.

Semen biology of vendace (Coregonus albula L.).

The objective of this study was to describe the morphometry and motility parameters of vendace (Coregonus albula) spermatozoa. Morphometric parameters of vendace sperm head and tail were of values similar to rainbow trout. The effects of pH, sodium, potassium and calcium ion concentrations on computer-assisted sperm analysis (CASA) sperm motility characteristics were tested.

Acrosome staining and motility characteristics of sterlet spermatozoa after cryopreservation with use of methanol and DMSO.

In this study we describe acrosome staining and motility characteristics of fresh and cryopreserved sterlet (Acipenser ruthenus L.) spermatozoa using soybean trypsin inhibitor-Alexa conjugate fluorescent staining and computer-aided sperm analysis (CASA), respectively. Methanol or dimethylsulfoxide (DMSO) were used as cryoprotectants.

Effects of different surfactants on motility and DNA integrity of brown trout (Salmo trutta fario) and common carp (Cyprinus carpio) spermatozoa.

In this study we evaluated effects of surfactants on motility parameters and DNA integrity of spermatozoa of freshwater teleost fish. Common carp (Cyprinus carpio) and brown trout (Salmo trutta fario) spermatozoa were exposed to either sodium dodecyl sulphate (SDS, anionic surfactant) or octoxynol 9 ( Triton X-100, nonionic surfactant). Both surfactants added at activation caused a decrease in sperm motility characteristics measured by computer-assisted sperm analysis (CASA).

Polymorphism of transferrin of carp seminal plasma: relationship to blood transferrin and sperm motility characteristics.

Transferrin (Tf) is a major protein of carp (Cyprinus carpio) seminal plasma. Its relationship with milt quality is unknown. In this study, we sought to determine if Tf is polymorphic in carp seminal plasma and if this polymorphism is related to sperm motility characteristics.

Influence of heavy metals and 4-nonylphenol on reproductive function in fish.

Many industrial and agricultural chemicals (including heavy metals and alkylphenols) present in the environment have adverse effects on the reproductive function in fish. Three studies were conducted to assess toxicity of these chemicals towards reproduction of freshwater fish. It was shown that heavy metals added to the diets accumulate in brain tissue of carp, and this accumulation results in inhibition of the secretion of noradrenaline and stimulation of the secretion of dopamine in the hypothalamus.

Application of biochemical markers for identification of biological properties of animal semen.

The use of biochemical markers for identification of biological properties of semen will help to develop new criteria that are accurate and objective in predicting and improving male fertility. Understanding and controlling the mechanisms involved in fertility is a key challenge, which is of fundamental importance in successful animal reproductive performance. Moreover, unraveling the unique molecular mechanism associated with sperm function might have considerable diagnostic value in the evaluation of male infertility.