Determination of appropriate dietry protein level of “Aspikutum”, a hybrid of Asp (Aspius aspius ♀) and Caspian Kutum (Rutilus frisii♂ )

Document Type : Research Paper

Authors

1 Fisheries Department, Faculty of Natural Resources, University of Guilan, Sowmeh Sara, Guilan, Iran

2 Dr. Yousefpour Fish Hatchery Center, Siahkal, Guilan, Iran

Abstract

This study was conducted to determine the effects of dietary protein levels on growth performance and body biochemical composition of “Aspikutum”, a hybrid between Asp (Aspius aspius ♀) and Caspian Kutum (Rutilus frisii ♂). Six iso-energetic diets containing six protein concentrations (28, 32, 36, 40, 44 and 48%) were tested with triplicate groups for 60 days. Fourteen fish with mean initial weight of 28.5 ± 0.72 g were stocked in each replicate using circular concrete tanks containing 400 liter of water. Fish were hand fed three times daily to apparent satiation. Results showed that the feed efficiency, specific growth rate, protein efficiency ratio, final weight, weight gain and condition factor were significantly affectedby dietary protein. These parameters were increased with increasing dietary protein to 36% and decreased in more protein levels. Body protein and ash contents were significantly different among the treatments. Body protein content increased significantly with increasing dietary protein to 36% and then decreased in 48% protein level. The present study revealed that the best growth performance of Aspikutum juveniles was achieved at 36% dietary protein level. Hence, according to the results and the economic aspect, diet with 36% protein is recommended for rearing juvenile Aspikutum.

Keywords