Hatching performance and yolk sac absorption of Abant trout Salmo abanticus T 1954

Salmo abanticus is a native to Lake Abant and it is known to be endemic to Turkey. The purpose of this study was to determine hatching performance, body and yolk weight at hatching, the growth rate during the yolk absorption and yolk conversion efficiency of Abant trout (S. abanticus, T., 1954) larvae, and the relationships between length, total wet weight, dry yolk body weights of alevins and degree/days. While the mean wet weight was 18.2±5.58 mg (n = 10) at hatching and reached 88.24±6.22 mg just before the swim-up stage, the mean dry weights of the body and yolk sac were 2.18±0.63 and 18.47±1.14 mg at hatching and 12.58±0.98 and 2.29±0.77 mg at swim-up stages, respectively. The mean body dry matter and water content of the larvae were 61.87 and 38.18% at hatching and 22.49 and 77.51% at swim-up stages, respectively. Our results indicated that dry yolk and total larval weights and dry matter of the larvae decreased, while dry body weight and water content increased with degree-days. The growth of larva, yolk sac absorption and yolk conversion efficiency were estimated as 0.29 mm/day, 0.39 mg/day and 0.64, respectively. Information on yolk sac absorption and hatching performance of this species would contribute to knowledge of management of the stocks