The Effect of Stocking Density on Growth Performance and Hematological Profile of Stellate Sturgeon (A.Stellatus, Pallas, 1771) Fingerlings Reared in an Industrial ,, Flow-Through’’ Aquaculture System

Abstract

Abstract  The most studied among sturgeonnative species, when we speak about growth performance in intensive aquaculturesystems is stellate sturgeon (Acipenserstellatus, Pallas1771). The level of intensity of an industrial growthsystem is given by its stocking density maximum level, which generally definesthe quantity of biomass per unit of volume.Thepresent paper aims to assess, in general terms, the production potential ofindustrial flow-through aquaculture systems for stellate sturgeon fingerlingsgrowth and especially to determine a certain stocking density that maintains apositive correlation between growth rate and physiological state of biologicalmaterial.The biologicalmaterial consists in a number of 1200 stellate sturgeon fingerlings, with anaverage weight of 5,52g ± 0.06 g, that were divided into six growth units bythree stocking densities, in replicate: 2,78 kg/m3 (V1),3,66 kg/m3 (V2) and 4,59 kg/m3 (V3).At the end of 40 days trial, the biological material was evaluatedphysiologically and in terms of growth.At theend of the experiment, the growth performance indicators registeredinsignificant values (p> 0.05), higher in case of the experimental variantwith lower stocking density. This variant also presents a better feedconversion ratio. The haematological profile remains constant for the threeexperimental variants. The only indicator that is significantly influenced (p<0.05) by stocking density is the hematocrit and implicitly the meancorpuscular volume.A higher stockingdensity for stellate sturgeon fingerlings growth in anindustrial flow-through aquaculture system did not significantly influenced thebiological material growth nor its physiological state but decreased thesurvival rate.