title: The type of spawning agent affects the egg composition during out-of-season spawning but not during in-season spawning in Eurasian perch, Perca fluviatilis.
abstract: The aim of the study was to verify the effect of various hormonal agents [human chorionic gonadotropin (hCG) and salmon gonadoliberine analogue (sGnRHa)] applied at different stages of maturity of the females [out-of-season (maturation stage I) and in-season spawning (maturation stages II and IV)] on the proximate composition (PC) and fatty acid (FA) profile of eggs of Eurasian perch, Perca fluviatilis. The egg samples (7 samples from each group) were also collected from spontaneous spawning (without hormonal treatment) fish representing each maturation stage (I, II and IV for groups C-I, C-II and C-IV, respectively). The results were also compared with the eggs collected in nature (seven randomly chosen egg samples from natural spawning; group NS). Embryonic survival rate was recorded and analysis of PC and FA profile were performed, for all the groups. Embryonic survival rate varied among the groups, and only differences (P<0.05) between group C-I and NS were recorded. In-season spawning operation did not affect PC and FA profiles. Application of hCG or spontaneous spawning (group C-I) were found to have the highest effect on the FA profile. It concerned mostly total n-3 polyunsaturated fatty acids, but also stearic (C18:0), oleic [C18:1(cis9)], linoleic [C18:2(n-6)], arachidonic [C20:4(n-6)] and docosahexaenoic[C22:6(n-3)] acids. The application of sGnRHa during out-of-season spawning had the lowest effect on the FA profile. The results presented indicate that controlled reproduction can affect the FA profile only during out-of-season spawning. This negative effect can be presumably compensated by the application of sGnRHa as a spawning agent.
authors.affiliation: Department of Lake and River Fisheries, University of Warmia and Mazury, ul. Oczapowskiego 2, 10-719 Olsztyn, Poland; Department of Aquaculture, Szent István University, Pater K. u.1, 2100 Gödöllő, Hungary. Electronic address: danielzarski@interia.pl.
authors.forename: Daniel
authors.initials: D
authors.lastname: Żarski
authors.affiliation: Department of Lake and River Fisheries, University of Warmia and Mazury, ul. Oczapowskiego 2, 10-719 Olsztyn, Poland.
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Palińska-Żarska
authors.affiliation: Department of Commodity Science and Food Analysis, University of Warmia and Mazury, ul. Oczapowskiego 2, 10-719 Olsztyn, Poland.
authors.forename: Joanna
authors.initials: J
authors.lastname: Łuczyńska
authors.affiliation: Department of Lake and River Fisheries, University of Warmia and Mazury, ul. Oczapowskiego 2, 10-719 Olsztyn, Poland.
authors.forename: Sławomir
authors.initials: S
authors.lastname: Krejszeff
mesh_terms: D000818:Animals; D006063:Chorionic Gonadotropin / Q000494:pharmacology*; D005227:Fatty Acids / Q000737:chemistry / Q000378:metabolism; D005260:Female; D007987:Gonadotropin-Releasing Hormone / Q000031:analogs & derivatives* / Q000494:pharmacology; D010063:Ovum / Q000737:chemistry / Q000187:drug effects* / Q000378:metabolism; D010471:Perches / Q000502:physiology*; D012098:Reproduction / Q000187:drug effects; D012621:Seasons
chemical_list: D006063:Chorionic Gonadotropin; D005227:Fatty Acids; D007987:Gonadotropin-Releasing Hormone; C058987:5-oxo-pro-his-trp-ser-tyr-gly-trp-leu-pro-glynh2
keywords: Egg quality; Fatty acid profile; Final oocyte maturation; GnRH; Hormonal treatment; Spawning induction; hCG