Effect of water temperature on the embryonic development and hatching results of rainbow trout (Oncorhynchus mykiss)

The authors hatched rainbow trout eggs in water of different temperature but of the same oxygen content and reaction. They found that at 7.55 degrees C hatching started on 43(rd) day and terminated on 45(th) day. There were no developmental anomalies on the spawns hatched at this temperature. With the increase of water temperature hatching time decreased. High mortality and developmental anomalies were observed in case of hatching at 13.42 degrees C. From developmental anomalies vertebral column deformities, bicephaly, twin development defects and distortion of tail and tail fin occur. The authors call the attention with their studies to the negative effect of the increase of temperature of reproductive environment in case of species living in mountain and submountain areas, using rainbow trout as a model.