title: In vitro storage of unfertilized eggs of the Eurasian perch and its effect on egg viability rates and the occurrence of larval malformations.
abstract: Ova ageing is the most important factor affecting fish egg quality after ovulation. Long-term storage of fish ova, using cryopreservation and vitrification techniques, has been unsuccessful to date. Instead, short-term in vitro ova storage has been used successfully and optimized in some cultured fish species. In vitro ova storage can drastically improve mass production of larvae and juveniles in the hatcheries by providing the possibility of the synchronous artificial fertilization for different females. To study how long unfertilized eggs of Eurasian perch (Perca fluviatilis L.) can retain their fertilizing ability after stripping, eggs were stored at temperatures of 4°C, 8°C and 12°C for 72 h post-stripping (HPS). The stored eggs of four female perch were separately fertilized at 0 h (i.e. control eggs fertilized before storage) and at 6-hour intervals during the experimental period of 72 h. The embryos reaching the eyed-egg and hatched-larvae stages, eyed-egg mortality and larval malformation rates were recorded as indices of egg quality. The results indicated that the maximum eyed eggs and hatched larvae (86% and 63%, respectively) were observed for eggs fertilized immediately after stripping, whereas the storage of the eggs at 4°C for 48 HPS decreased the eyed-egg and hatched-larvae rates to 46% and 17%, respectively. The use of a higher storage temperature resulted in a more rapid decrease in egg viability: eyed-egg and hatched-larvae rates of 23% and 9%, respectively, were obtained after 48 HPS storage at 8°C and 2% and 1% for eggs stored at 12°C. Eyed-egg mortality and larval malformation rates were not significantly affected by post-stripping ova ageing for at least up to 36 h. Thereafter, both values increased significantly and were measured to be the highest in the most aged ova. The present study demonstrated that stripped Eurasian perch eggs can be stored for at least 12 h at 4°C to 12°C without a significant reduction in their quality.
authors.affiliation: 1University of South Bohemia in Ceske Budejovice,Faculty of Fisheries and Protection of Waters, South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses,Research Institute of Fish Culture and Hydrobiology,Zátiší 728/II,389 25 Vodňany,Czech Republic.
authors.forename: A M
authors.initials: AM
authors.lastname: Samarin
authors.affiliation: 2Department of Aquaculture,Szent István University,Páter Károly u. 1,2100 Gödöllő,Hungary.
authors.forename: D
authors.initials: D
authors.lastname: Żarski
authors.affiliation: 3Department of Lake and River Fisheries,University of Warmia and Mazury,ul. Oczapowskiego 2,10-719 Olsztyn,Poland.
authors.forename: K
authors.initials: K
authors.lastname: Palińska-Żarska
authors.affiliation: 3Department of Lake and River Fisheries,University of Warmia and Mazury,ul. Oczapowskiego 2,10-719 Olsztyn,Poland.
authors.forename: S
authors.initials: S
authors.lastname: Krejszeff
authors.affiliation: 1University of South Bohemia in Ceske Budejovice,Faculty of Fisheries and Protection of Waters, South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses,Research Institute of Fish Culture and Hydrobiology,Zátiší 728/II,389 25 Vodňany,Czech Republic.
authors.forename: M
authors.initials: M
authors.lastname: Blecha
authors.affiliation: 3Department of Lake and River Fisheries,University of Warmia and Mazury,ul. Oczapowskiego 2,10-719 Olsztyn,Poland.
authors.forename: D
authors.initials: D
authors.lastname: Kucharczyk
authors.affiliation: 1University of South Bohemia in Ceske Budejovice,Faculty of Fisheries and Protection of Waters, South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses,Research Institute of Fish Culture and Hydrobiology,Zátiší 728/II,389 25 Vodňany,Czech Republic.
authors.forename: T
authors.initials: T
authors.lastname: Policar
mesh_terms: D000818:Animals; D002470:Cell Survival; D015925:Cryopreservation / Q000662:veterinary*; D005260:Female; D005307:Fertilization in Vitro; D007814:Larva / Q000254:growth & development; D010063:Ovum / Q000502:physiology*; D010471:Perches / Q000502:physiology*; D013696:Temperature
keywords: 
                 Perca fluviatilis L.; egg storage; egg viability; stripping; temperature