Effects of stocking density on reared Siberian sturgeon (Acipenser baerii) larval growth, muscle development and fatty acids composition in a recirculating aquaculture system

Abstract

This study evaluated the effects of rearing density on muscle growth and development in Siberian sturgeon (Acipenser baerii) larvae. Three different stocking densities were tested: low (LD, 30 larvae/l), mid (MD, 80 larvae/l) and high (HD, 150 larvae/l) in a recirculating aquaculture system. Larvae were sampled at hatching (T0), schooling (T1) and complete yolk-sac absorption (T2) stage and were weighed and processed for muscle tissue histometrical analyses and for qualitative morphological study analyses; fatty acid profile was also determined by Gas Chromatography-Flame Ionization Detector analysis. Low-density larvae presented a higher weight than MD or HD at T2 (p < 0.05). Histometrical analysis revealed that total muscle area was similar at T1 and T2, but higher than T0, while it was lower at HD at schooling (p < 0.05). The fatty acid profile revealed no differences between densities while, during development, there was a selective consumption: sparing or increasing of essential fatty acids to the detriment of their precursors. Our study suggests that lower densities appear to be more suitable to rear Siberian sturgeon in this particular stage of development. Indeed, larvae reared at the lower density were heavier and longer while larvae reared at the higher density showed lower muscle proliferation rate. As a consequence, LD larvae may exert an increase of potential growth at a mid-long term. K E Y W O R D S density, fatty acids, larvae, muscle structure, Siberian sturgeon 1 | INTRODUCTION During the past two centuries, the natural stocks of Siberian sturgeon (Acipenser baerii) suffered a sharp decline, due to overfishing, pollution and loss of spawning spots. In 1998, all sturgeon species were effectively added to the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), which allowed to control the illegal trade of sturgeons and their products and the implementation of conservation plans.Survival and growth during early stages of development of Siberian sturgeon and throughout the following life periods is of great importance both for conservation aquaculture production programs and for commercial purposes. Following an increased demand of commercial production facilities, there is a growing need for the improvement of hatchery technologies that allow the production of high quality Siberian sturgeon larvae. After hatching, only endogenous feeding occurs (Balon, 2001), when larvae entirely rely on the yolk-sac reserves for energy and growth, until its digestive system is

How Different Stocking Densities Affect Growth and Stress Status of Acipenser baerii Early Stage Larvae

“…As for growth-related genes expression, overall, it seems that high densities (particularly MD) lead to a higher expression of both igfs and myog at T2 when compared to T1. Reference [62] observed that Siberian sturgeon larvae subjected to LD and MD presented higher muscle fibers proliferation at the end of the trial, as well as a higher area of polygonal fast fibers, when compared to HD. These results are consistent with what was obtained in the present study, taking into account that IGFs in fish stimulate myogenic cells proliferation and differentiation [63,64] and that the gene myog is a marker of myogenic cell recruitment for stratified hyperplasia in teleosts [65].…”

Singular or combined dietary administration of multi‐strain probiotics and multi‐enzyme influences growth, body composition, digestive enzyme activity, and intestinal morphology in Siberian sturgeon ( Acipenser baerii )

“…Farming of sturgeons is economically and ecologically important due to their high nutrition values (meat and caviar) and prevents their mass extinctions from natural ecosystems (Chebanov & Galich, 2018; Geraylou et al, 2013). Siberian sturgeon ( Acipenser baerii , Brandt, 1869) has some potential characteristics such as fast growth, high compatibility with artificial diets, tolerance to unfavourable environmental conditions and a short period of sexual maturity makes it an ideal species compared to other sturgeons (Acipenseridae) for aquaculture operations (Aidos et al, 2019; Fopp‐Bayat et al, 2007).…”

The effect of stocking density on sterlet Acipenser ruthenus (Linnaeus, 1758) larvae in the recirculating aquaculture system

“…An increase in stocking density in the present study did not have effect on growth of sterlet larvae. The productivity of aquaculture systems can be increased by increasing the number of cultured fish per volume unit (Aidos et al, 2018;Barros et al, 2019;Montero et al, 1999). On the other hand, this may impact water quality and welfare status visible in culture performance, physiological status, and the behavior of farmed fish.…”

“…For farms and hatcheries, it is important to keep up with the increasing demands for both meat production and restocking purposes which can be achieved by having large quantities of juveniles. The efficiency of intensive aquaculture systems might be optimized by increasing the stocking density (Aidos et al, 2018; Barros et al, 2019). High rearing density may have a disadvantageous impact on fish culture proven to impair physiological status in various teleosts as well as the welfare and behaviour of reared fish (Barros et al, 2019; Bolasina et al, 2006; Lupatsh et al, 2010; Montero et al, 1999).…”

“…For farms and hatcheries, it is important to keep up with the increasing demands for both meat production and restocking purposes which can be achieved by having large quantities of juveniles. The efficiency of intensive aquaculture systems might be optimized by increasing the stocking density (Aidos et al, 2018;Barros et al, 2019).…”