Cel The objective of this investigation is to contribute to the knowledge on handling, shipping and preservation of male and female gametes and embryos in rainbow trout (Oncorhunchus mykiss). Research has been carried out to increase knowledge on handling and preservation of male and female gametes and embryos in rainbow trout (Oncorhynchus mykiss). Long term trials using melatonin implants have been conducted. Analyses for plasma melatonin, steroids, vitellogenin and spawning times are in progress. As a first step an enzyme linked immunosorbant assay (ELISA) system was set up. Using this system, fully validated homologous ELISAs have been established for estradiol and testosterone. An ELISA for melatonin is near completion. Furthermore, a technique to introduce permanently indwelling catheters in trout has been established. The number of sperm required to fertilize an egg before and after cryopreservation has been determined. The results show that 2E6 frozen thawed spermatozoa per egg gave satisfactory fertilization rates. To be on the safe side, 3E6 is recommended. Since the number of fresh spermatozoa per egg required for optimal fertilization was between 2E5 and 3E5, 15 times more frozen spermatozoa are needed. Preliminary experiments, aimed at the freezing of eggs show that there are solution effects from the cryoprotectants on the survival of eggs and embryos. Best survival rates were achieved with isotonic solution and the cryoprotectants sucrose and ethyleneglycol. The storage of eggs or embryos in straws has been shown to be a satisfactory method which does not effect gamete viability. Fertilized eggs showed better survival in all experimental procedures than unfertilized eggs.In order to have a steady supply of gametes available, fish will be subjected to either a 6 months compressed light programme or melatonin treatment. In order to study the effect of these treatments in depth and obtain physiological cues as to the times when vitellogenesis occurs and mature gametes are available, serum profiles of the relevant reproductive hormones and vitellogenin will be established. Housing and treatment of fish, collection of gametes and experiments involving handling, storage and preservation as well as fertilization trials will be conducted in Gottingen. Hormone and vitellogenesis determinations will be conducted in Sheffield. Unfertilized eggs and embryos at different stages of development will be stored at various temperatures from 4 C downwards. The suitability of extenders (eg sucrose) and cryoprotectants as well as different temperatures and cooling and warming rates will be investigated. Special attention will be given to a new freezing technique, called vitrification, which avoids formation of membrane damaging ice crystals. Recently this technique has been successfully applied in this laboratory for the freezing of mammalian embryos. Concerning cryopreservation of rainbow trout sperm, a series of trials will be conducted in order to improve the sucrose extender and its adaptation to the application under field conditions. It will also be attempted to freeze dry trout sperm after appropriate pretreatment (sucrose, vitrification medium). Dziedzina nauki medical and health sciencesmedical biotechnologyimplantsmedical and health sciencesclinical medicineembryologynatural sciencesbiological sciencesbiochemistrybiomoleculesproteinsenzymes Program(-y) FP2-FAR - Community research and coordination programmes (EEC) in the fisheries sector, 1988-1992 Temat(-y) Data not available Zaproszenie do składania wniosków Data not available System finansowania Data not available Koordynator GEORG-AUGUST-UNIVERSITY GOETTINGEN Wkład UE Brak danych Adres Albrecht-Thaer Weg 3 37075 GOETTINGEN Niemcy Zobacz na mapie Koszt całkowity Brak danych Uczestnicy (1) Sortuj alfabetycznie Sortuj według wkładu UE Rozwiń wszystko Zwiń wszystko University of Sheffield Zjednoczone Królestwo Wkład UE Brak danych Adres Western Bank S10 2TN Sheffield Zobacz na mapie Koszt całkowity Brak danych
