Spermatozoa quality and sperm lipid composition in intensively cultured and wild burbot (Lota lota).

The aim of this study was to compare the spermatozoa quality parameters in spermatozoa of RAS (Recirculating Aquaculture System; RAS group) cultured (commercial pellets) and natural condition cultured (WILD group) burbot Lota lota (live prey, Pseudorasbora parva). Seven of nine fish of the RAS group produced sperm, with sperm from only four of the fish having a motility of >5%. Sperm were collected from all nine fish of the WILD group, and sperm of six of the fish from the WILD group had motility of about 100% and three had sperm with 50% to 60% motility.

Cryopreservation effects on a viable sperm sterlet (Acipenser ruthenus) subpopulation obtained by a Percoll density gradient method.

In many fish species, sperm cryopreservation has deleterious effects and leads to a significant decrease in spermatozoa viability. However, the effect of cryopreservation on sperm cells that survive this process and are still viable is not fully understood. The objective of this study was to compare the viability and proteomes of fresh and cryopreserved sterlet (Acipenser ruthenus) sperm samples before and after live-dead cell separation using Percoll density gradient centrifugation.

Consequences of uncontrolled cooling during sterlet (Acipenser ruthenus) sperm cryopreservation on post-thaw motility and fertilizing ability.

The significant influence of the number and position of fish sperm sample straws in uncontrolled cooling devices on post-thaw spermatozoa parameters, such as motility and fertilizing ability, is presented in this study. The two most popular uncontrolled cooling devices were used in this study: a Styrofoam box setup with a polystyrene floating raft on liquid nitrogen and the dry shipper setup with a straw holder. We tested the effect of different quantities of straws (6 or 60) placed on the polystyrene floating raft and the position of the straws in the holder (on the periphery or in the centre).

Lipid composition in common carp (Cyprinus carpio) sperm possessing different cryoresistance.

The present study examined the lipid composition of plasma membranes in carp sperm with different post-thaw motility. The approach adapted for carp sperm cryopreservation, which involves the selection of the most effective protocol for individual males by comparing two cryoprotective media, was applied to the cryopreservation procedure. Sperm motility prior to freezing was greater than 80% but decreased to 40% in one group and to 10% in another group following cryopreservation.