Comparison of temperature shock timing to induced artificial mitotic gynogenesis and androgenesis in common tench

Abstract

The aim of the study was to determine the optimum temperature shock timing to induce androgenetic and gynogenetic growth in common tench (Tinca tinca L.). UV radiation at the dose of 3,456 J m−2 was used to inactivate the genome of oocytes (androgenesis) and sperm (gynogenesis). In each case, the optimum timing was sought (between 20 and 60 min) before the beginning of diploidization of genetic material with a temperature shock (40 °C, duration 2 min). Eggs were incubated under laboratory conditions at 21 °C. The highest survival rate for androgenotes was observed after the temperature shock was applied for 30 min and for gynogenotes 40 min after the activation. The survival rate for embryos did not exceed 2 % in the best variants, either in andro- or gynogenesis. A negative correlation was found to exist between the quality of spawn and the occurrence of spontaneous andro- and gyno-genotes.