Growth performance of carp fishes reared in polyculture in a warm water reservoir

Lyudmila Nikolova, Yosif Rabadzhiyski

Abstract: The growth performance of carp fishes reared in polyculture in a small warm water reservoir with an area of 9.8 ha, located in the central part of Southern Bulgaria, was studied. Polyculture included: scale and mirror carp (Cyprinus carpio L. – K1), bighead carp (Hypophthalmichthys nobilis Rich. – T1) and grass carp (Ctenopharyngodon idella Val. – A1) at the following stocking rate: K1 scale – 510 pcs/ha, average live weight of 0.287 ± 0.004 kg; K1 mirror – 510 pcs/ha, average live weight 0.297 ± 0.002 kg; T1 – 150 pcs/ha, average live weight 0.492 ± 0.004 kg; A1 – 50 pcs/ha, average live weight 0.499 ± 0.003 kg. The carp and the grass carp fishes were fed on wheat (65%) and barley (35%). The total fish growth was 2632.4 kg/ha, the carp growth being 75.6%, the bighead carp – 19.6% and the grass carp – 4.8%. Natural fish productivity was 37.2% of the total growth. The total feed coefficient was 3.1 kg/kg-1, and for the carp and grass carp – 3.9 kg/kg-1. The highest survival rate was reported for the grass carp – 96%, for the bighead carp it was 93.3% and for the carp – 89% for the mirror and 91% for the scale carp. During the fattening period the live weight of the scale carp increased 8.8 times, of the mirror carp 8.5 times, of the grass carp 6.1 times, and of the bighead carp 8.4 times, respectively.

Keywords: carp; herbivorous fish; polyculture; reservoir

Date published: 2019-12-04