Vojtěch Kašpar

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Broodstock selection programs are currently underway for Atlantic cod (Gadus morhua). To complement and further these selection programs we need to develop sperm cryopreservation procedures. This will allow genomic DNA from males from selected individuals or stocks to be frozen and conserved in perpetuity. In our study we used a full factorial ANOVA design(More)
In the present review, sperm morphology, acrosome reaction, motility, short-term storage and cryopreservation are summarized and discussed in sturgeon (Chondrostei, Acipenseriformes). The elongated head of spermatozoon comprises an acrosome with 8–12 posterolateral projections. Usually three endonuclear canals are observed in the nucleus. Proximal and(More)
The North American spiny-cheek crayfish, Orconectes limosus (Cambaridae), endangered in its native range, is a widespread invasive species in European waters and conservationally important carrier of crayfish plague. However, its population structure is poorly known, and no informative genetic markers for the species are available. We tested cross-species(More)
Spermiation and changes in androgen (testosterone, T and 11-ketotestosterone, 11-KT) levels were studied in sterlet (Acipenser ruthenus) treated with GnRH agonist implants (dAla6-Pro9-LHRHa) at 25 and 75 μg kg−1 b.w. and compared with those males treated with 4 mg kg−1 b.w. of carp pituitary extract (CPE) and 3 pellets of Ovopel kg−1 b.w., which contains(More)
Sturgeons (chondrostean, acipenseridae) are ancient fish species, widely known for their caviar. Nowadays, most of them are critically endangered. The sterlet (Acipenser ruthenus) is a common Eurasian sturgeon species with a small body size and the fastest reproductive cycle among sturgeons. Such species can be used as a host for surrogate production;(More)
The sperm of sterlet (Acispenser ruthenus) was used to investigate the effect of the xenobiotic tetrabrombisphenol A (TBBPA) on sperm quality variables (ATP content, spermatozoa motility, and velocity), DNA integrity, and oxidative stress indices. Sperm was diluted to obtain a spermatozoa density of 5 × 10(8) cells/mL and exposed for 2 h to final(More)
Spermatozoa of common carp Cyprinus carpio are typically consist of a primitive head without acrosome, a midpiece with several mitochondria, a centriolar complex (proximal and distal centriole), and one flagellum. During an evaluation of the motility of common carp spermatozoa, we found spermatozoa with more than one flagellum and/or "double head" in three(More)
Alternative reproductive tactics (ARTs) are prevalent in nature, where smaller parasitic males typically have better sperm quality than larger territorial guard males. At present, it is unclear what is causing this phenomenon. Our objective was to gain insights into sperm form and function by examining flagellar beating patterns (beat frequency, wave(More)
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