Comparison of Metabolic Rates of Young of the Year Beluga (Huso huso), Sterlet (Acipenser ruthenus) and Bester Hybrid Reared in a Recirculating Aquaculture System

Abstract

In the present study, oxygen consumption of two sturgeon species, beluga (Huso huso), sterlet (Acipenser ruthenus), and their hybrid reared in a recirculating aquaculture system were compared over body intervals from 54–107 g to determine the interspecific variation of metabolic rate. Metabolic rates were measured using the intermittent-flow respirometry technique. Standard oxygen consumption rates (SMR, mg O2 h−1) of sterlet were 30% higher compared with beluga and 22% higher compared with bester hybrid. The routine metabolic rate (RMR, mg O2 h−1) averaged 1.58 ± 0.13 times the SMR for A. ruthenus, 1.59 ± 0.3 for H. huso, and 1.42 ± 0.15 for the hybrid bester. However, the study revealed no significant differences (p > 0.05) between mean values of SMR and RMR for beluga and bester hybrid. The scaling coefficient reflected a closed isometry for the hybrid (b = 0.97), while for the purebred species the coefficient of 0.8 suggests a reduction in oxygen consumption with increasing body mass. These findings may contribute to understanding the differences in growth performances and oxygen requirements of the studied species reared in intensive aquaculture system.

A Study on the Metabolic Rate Change Pattern in F2 Hybrid Sturgeon, the Bester (Huso huso × Acipenser ruthenus), during the Early Developmental Stage

“…The ultimate goal of aquaculture is to maximize the growth and development of aquaculture species with minimal costs [1,2]. To this end, fishery-related industries have been developed using research and knowledge from fields including biology, ecology, animal behavior, and engineering [3][4][5]. The rapid development of highly intensive production systems, such as recirculating aquaculture systems (RASs), has resulted in the timely integration of engineering studies for optimizing waste management (including system design) and biological studies for understanding the physiological requirements of individual aquaculture species [3,4].…”

“…To this end, fishery-related industries have been developed using research and knowledge from fields including biology, ecology, animal behavior, and engineering [3][4][5]. The rapid development of highly intensive production systems, such as recirculating aquaculture systems (RASs), has resulted in the timely integration of engineering studies for optimizing waste management (including system design) and biological studies for understanding the physiological requirements of individual aquaculture species [3,4]. However, the water pumps and oxygen supply in RASs are very expensive; thus, determining the oxygen consumption of each aquaculture species is an essential aspect of cost-efficient aquaculture under intensive conditions [6][7][8].…”

“…Several studies have found that breeding under moderately high levels of dissolved oxygen (i.e., moderate hyperoxia) promotes the growth of organisms [18,19,21]; however, according to a study on Salmonidae, long-term exposure to hyperoxia could lead to problems such as oxidative stress and increased disease susceptibility [22]. These findings indicate that understanding the metabolic rate of aquaculture species is essential for establishing optimal breeding conditions that promote growth and survival under intensive production conditions, such as those in RASs, because the appropriate dissolved oxygen level (i.e., neither hypoxic nor hyperoxic conditions for each species) can only be predicted when the pattern of metabolic rate changes is clearly identified [3].…”

“…Despite this fact, most studies on the metabolism of Acipenseridae have focused on fish in their juvenile or adult stages and/or have been limited to purebred fish [3]; thus, studies on artificial hybrids, such as the F 1 or F 2 bester, which are created to increase breeding efficiency are lacking, as are studies on their metabolic changes during early development when rapid physiological, ecological, and morphological changes occur. Considering that the breeding of larvae and fry is the most difficult hatchery process during the breeding of Acipenseridae species [36], obtaining fundamental data that help breeders determine the appropriate oxygen demand and/or create an optimal breeding condition for this species are critical.…”