Short term storage of unfertilized rainbow trout (Oncorhynchus mykiss) eggs in artificial containment environment

This study was conducted with rainbow trout (Oncorhynchus mykiss), the dominant species in Turkish aquaculture. The aim was to investigate the effects of storing freshly stripped unfertilized raw eggs in a refrigerator (+4°C) until fertilization on hatchery performance. For this purpose, 3 different artificial preservation solutions (YM) identical to the analyzed ovarian fluid density were designed. KCl, NaCl, CaCl2, MgCl2 and NaHCO3 were used at different rates in YM solutions to ensure electrolyte balance. 5 female fish, 51.2±0.812 cm long and 1945.2±178.969 g in weight, were used from 4-year-old fish randomly sampled from the stock. Egg diameters taken from the fish varied between 5.03-5.13 (5.1±0.05). Three Control (K) groups, 3 Artificial Storage (YM1) groups, 3 YM2 and 3 YM3 groups were formed from the egg pool prepared with equal amounts of eggs taken from the egg groups, with 150 eggs per group. The groups were stored in a refrigerator at +4°C for three different periods. In the control group and YM groups, fertilization was performed with sperm pools mixed with equal amounts of sperm fluid taken from male fish of 38.9±4.510 cm length and 798.4±305.107 g. At the end of the study, differences within and between groups were examined and the applicability of survival rates were examined. The best hatchery performance up to hatching among all groups was in the K group with 88.4%. The YM1 group showed the best success with a survival rate of 55,8±6.34% after one day of storage. These results showed that in cases of necessity, they can be kept in a refrigerator for 24 hours with YM1 solution.