Analysis of Reproductive Performance of Rainbow Trout ( Oncorhynchus mykiss) Broodstock in a Commercial Farm in Eastern Black Sea Region
In this study reproductive performance of female rainbow trout broodstock ( Oncorhynchus mykiss) in a commercial trout farm in Eastern Black Sea Region were evaluated during 1995 spawning season. Mean total and relative fencundity values were 2304±425 egg/individual and 1364±281 egg/kg, respectively, while mean egg dia meter was 5.2±0.21 mm. Fertilisation rate on average was 73.7% of total fencundity. 84.6% of the fertilised eggs was eyed and 96.0% of those eyed was hatched. Larvae reached free swimming stage after 23 days and survival rate was 98.9% of those hatched larvae. Larvae reached a mean weight of 305±56 mg at 40th and 19.2±5.41 g 133th days after hatching. There was significant but weak positive relationship between female weights - fecundity and egg diameter, while the relationships between fertilisation -eyeing, hatching and free swimming rates were strong. It has been concluded that reproductive values determined during this study seems to be quite satisfactory for a typical commercial trout farm which has not got any broodstock management stragety, but it is possible to increase these values.
Analysis of Reproductive Performance of Rainbow Trout ( Oncorhynchus mykiss) Broodstock in a Commercial Farm in Eastern Black Sea Region
In this study reproductive performance of female rainbow trout broodstock ( Oncorhynchus mykiss) in a commercial trout farm in Eastern Black Sea Region were evaluated during 1995 spawning season. Mean total and relative fencundity values were 2304±425 egg/individual and 1364±281 egg/kg, respectively, while mean egg dia meter was 5.2±0.21 mm. Fertilisation rate on average was 73.7% of total fencundity. 84.6% of the fertilised eggs was eyed and 96.0% of those eyed was hatched. Larvae reached free swimming stage after 23 days and survival rate was 98.9% of those hatched larvae. Larvae reached a mean weight of 305±56 mg at 40th and 19.2±5.41 g 133th days after hatching. There was significant but weak positive relationship between female weights - fecundity and egg diameter, while the relationships between fertilisation -eyeing, hatching and free swimming rates were strong. It has been concluded that reproductive values determined during this study seems to be quite satisfactory for a typical commercial trout farm which has not got any broodstock management stragety, but it is possible to increase these values.
