High stocking density produces crowding stress altering some physiological and biochemical parameters in gilthead seabream, Sparus aurata , juveniles (original) (raw)

Effect of different stocking densities on growth, oxidative stress, antioxidant enzymes, and hematological and immunological values of European catfish (Silurus glanis L., 1758)

Aquaculture International, 2023

In this study, effect of different stocking densities on growth, oxidative stress, antioxidant enzymes, and hematological and immunological values in European catfish (Silurus glanis) was examined. The control (0.06 kg fish/L) and trial (T) 1 (0.08 kg fish/L), T2 (0.10 kg fish/L), and T3 (0.12 kg fish/L) stocking groups were used. Each stocking group with three replicates was carried out in a tank at 22 ± 2 °C water temperature. The fish were fed three times daily for 60 days. The highest final weight (123.3–171.6 g), weight gain (84.13–159.6%), specific growth rate (1.40–2.66%), feed intake (138.5–178.2 g/fish), and feed conversion rate (1.12–1.65%) were provided from the control and T1 stockfish (p > 0.05), followed by the T2 and T3 stockfish (p < 0.05), respectively. The lowest oxidant level and the highest reduced glutathione level and superoxide dismutase, catalase, and glutathione peroxidase activities were obtained from the control fish, followed by the T1, T2, and T3 stockfish, respectively (p < 0.05). In addition, parallel to the increase in stocking density, the erythrocyte count, hematocrit, hemoglobin, erythrocyte volume, corpuscular hemoglobin, and corpuscular hemoglobin concentration values of fish increased (p < 0.05), but the leukocyte count, nitroblue tetrazolium activity, total protein, and immunoglobulin- M values decreased (p < 0.05). The high stocking densities caused oxidative stress in fish, negatively affecting their health and growth and feed evaluation values. However, the stocking density could increase to 0.08 kg/L from 0.06 kg/L in the European catfish fingerling reared in the recirculating aquaculture system by maintaining the water quality and applying good care and feeding.

Effects of Stocking Density on Blood Cortisol , Glucose and Cholesterol Levels of Immature Siberian Sturgeon ( Acipenser baerii Brandt

2013

Siberian sturgeon (Acipenser baerii Brandt, 1869) is a suitable species for aquacultural purposes. This study was conducted to investigate the influence of stocking density on blood parameters of cultured immature Siberian sturgeon introduced to Iranian aquaculture systems, in order to monitor crowding stress. Two-year old juvenile fish (weight 607.7±21.49 g, total length: 68±9.46 cm [mean ± SE]) were reared at low, moderate and high densities (6, 12 and 18 fish 250 L, respectively) for 5 months. Cortisol, glucose and cholesterol concentration of blood plasma were measured four times during the experiment (July, August, October and November 2008). The present study indicated that (1) density had no significant effect of blood cortisol, glucose and cholesterol concentration in A. baerii (cortisol: 7.8-13.1, cholesterol: 115.6133.9, glucose: 41.4-46.8 ng ml[range]) (2) a significant increase in cortisol concentration of all densities was found in August which was related to water temp...

Physiological Response of Asian Seabass Reared in Recirculating Aquaculture System under Different Stocking Densities

Indian Journal of Animal Research

Background: There is a gap that we will need to use innovative solutions to produce more food and nutrition. RAS is a continuous water-flowing system that can induce schooling behaviour, a phenotypic character seen in Asian seabass that could help cut down cannibalism at a certain level. Stocking density is one of the critical factors affecting the growth, survival and health status of animals, which can influence the antagonistic behaviour pattern, hierarchical phenomena and cannibalistic nature of Asian seabass during the early life stage. Methods: A 60-day trial was conducted to evaluate the effect of different stocking densities (70, 140, 210, 280 and 350 fish/m3) on biochemical and stress gene expression of Asian seabass (Lates calcarifer) reared in Recirculating Aquaculture System by following a completely randomized design with four replications. Result: The study found that fish reared at 350 fish/m3 had significantly higher haemoglobin and red blood cells. In the case of bi...