5/20/2016

PhD defence of Gergő

Today Gergely Bernáth from our group has succesfully defended his PhD entitled "Development of fish sperm qualification systems for economic purposes". 

The committee evaluated Gergő's work with outstanding credit points.





5/17/2016

Another new paper accepted

A new paper by our group with the first authorship of Gergely Bernáth was accepted for publication in Animal Reproduction Science. For more information, please consult this link: http://www.sciencedirect.com/science/article/pii/S0378432016302226

Commercial-scale out-of-season cryopreservation of Eurasian perch (Perca fluviatilis) sperm and its application for fertilization

Abstract
The quality and fertilizing capacity of perch (Perca fluviatilis) sperm collected outside of the spawning season (off-season) and cryopreserved at a commercial scale, were tested. Basic parameters (equilibration time, dilution ratio, sperm concentration, post-thaw motility duration) which can have a significant effect on cryopreservation success were systematically investigated for effects on sperm quality using computer assisted sperm analysis (CASA). No significant decrease in progressive motility (pMOT) and straightness (STR) of fresh-diluted sperm was recorded among groups equilibrated for 0, 30 or 60 minutes in an extender with cryoprotectants. Curvilinear velocity (VCL) was reduced significantly after 30 minutes (30 min: 146 ± 15 μm/s, 60 min: 124 ± 18 μm/s) of equilibration compared to the control (174 ± 9 μm/s). After thawing, no decrease in pMOT or VCL was observed at different equilibration times in any of the analyzed groups. No correlation was observed among progressive motility, dilution ratios (p = 0.7) and cell concentrations (p = 0.1). The use of different activating solutions resulted in similar pMOT and VCL in the first 120 seconds post-thaw. Nevertheless, post-thaw sperm motility was reduced after 30 seconds using all activators. Motility parameters with low variation were recorded after thawing of 57 straws (pMOT: 37 ± 7%, VCL: 92 ± 10 μm/s, STR: 89 ± 3%). Ten randomly selected straws from commercial-scale cryopreservation resulted in a high fertilization rate (cryopreserved sperm: 72 ± 14%, fresh control: 94 ± 2%). An optimized commercial-scale cryopreservation protocol was successfully developed for Eurasian perch. The applicability of the off-season collected perch sperm for cryopreservation and fertilization was demonstrated.

5/10/2016

New paper accepted in General and Comparative Endocrinology

A new paper by our group was accepted for publication in General and Comparative Endocrinology as a part of the proceedings of last year's 5th International Workshop on the Biology of Fish Gametes held in Ancona, Italy on September 7-11, 2015. For more information please consult this link: http://www.sciencedirect.com/science/article/pii/S0016648016301319

DEVELOPMENT OF SPERM VITRIFICATION PROTOCOLS FOR FRESHWATER FISH (EURASIAN PERCH, Perca fluviatilis) AND MARINE FISH (EUROPEAN EEL, Anguilla anguilla)

Abstract
Vitrification was successfully applied to the sperm of two fish species, the freshwater Eurasian perch (Perca fluviatilis) and marine European eel (Anguilla anguilla). Sperm was collected, diluted in species-specific non-activating media and cryoprotectants and vitrified by plunging directly into liquid nitrogen without pre-cooling in its vapor. Progressive motility of fresh and vitrified-thawed sperm was evaluated with computer-assisted sperm analysis (CASA). Additional sperm quality parameters such as sperm head morphometry parameters (in case of European eel) and fertilizing capacity (in case of Eurasian perch) were carried out to test the effectiveness of vitrification. The vitrification method for Eurasian perch sperm resulting the highest post-thaw motility (14 ± 1.6%) was as follows: 1:5 dilution ratio, Tanaka extender, 30% cryoprotectant (15% methanol + 15% propylene-glycol), cooling device: Cryotop, 2 μl droplets, and for European eel sperm: dilution ratio 1:1, with 40% cryoprotectant (20% MeOH and 20% PG), and 10% FBS, cooling device: Cryotop, with 2 μl of sperm suspension. Viable embryos were produced by fertilization with vitrified Eurasian perch sperm (neurulation: 2.54±1.67%). According to the ASMA analysis, no significant decrease in head area and perimeter of vitrified European eel spermatozoa were found when compared to fresh spermatozoa.

Summer Course in Aquaculture

The Department of Aquaculture of Szent István University is organizing a CEEPUS Summer Course in Aquaculture on July 07-09th, 2016. 

For more information, please consult this link: http://mkk.szie.hu/dep/halt/ceepus_summer_course_2016/