Stocking density in Colossoma macropomum larviculture, a freshwater fish, in recirculating aquaculture system

Abstract

This study aimed to investigate stocking density during larviculture of Colossoma macropomum in recirculating aquaculture system with slightly saline water. Densities of 10 (D10), 30 (D30) and 50 (D50) larvae/L were tested with five replicates each. Larvae were fed with Artemia nauplii during the first 15 days and with commercial diet from day 16 to day 30. Water was maintained at a salinity of 2.01 ± 0.41 g of salt/L, and performance and survival were evaluated throughout the experiment. At the end of the experiment, larvae of each tank were classified according to size as small—S (<18.0 mm and <0.08 g), medium—M (>18.0 mm and <22.2 mm, >0.08 g and <0.15 g) and large—L (>22.2 mm and >0.15 g), and the size distribution was calculated for each stocking densities evaluated. Larval weight, length and specific growth rate were not affected by the tested stocking densities throughout the experiment (p > .05). Heterogeneity was recorded at 30 days of larviculture for all tested densities with a predominance of class M animals. Survival during feeding with Artemia was not affected by the tested densities (p > .05). Survival during feeding with commercial diet was highest for D10 and lowest for D30 (p < .05). Global survival, considering the experiment as a whole, was similar among the tested stocking densities (p > .05). Larviculture of C. macropomum can be successfully carried out at stocking densities of up to 50 larvae/L during the first 30 days of rearing in slightly saline water in recirculating aquaculture system.

Salinized water as a strategy for increase stocking density in Heros severus larviculture, an Amazonian ornamental fish

“…Salinized water as a strategy for increase stocking density in Heros severus larviculture, an Amazonian ornamental fish Larviculture is considered the most important and critical stage of aquaculture production chain, once it is the phase of higher animal fragility (Evangelista et al, 2020;Reis et al, 2021;Santos et al, 2021). The larvae are sensitive to several stressful factors such as pathogenic infections, productive managements and changes in water parameters, which can lead to high mortality rates and reduce productivity (Zuanon et al, 2011;Dias et al, 2016;Abe et al, 2019).…”

“…Thus, the success of larviculture is determined by the optimal culture conditions, aiming to guarantee the adequate fish development (Dias et al, 2016;Campelo et al, 2019a;Abe et al, 2021). In this scenario, the effects of salinized water and stocking density of fish are some of the factors that should be studied, since they can directly affect the larviculture management (Luz et al, 2012;Dias et al, 2016;Santos et al, 2021).…”

“…The use of an adequate stocking density is commercially beneficial, once it improves the use of tanks and water resources, in addition to maximizing economic results (Santos et al, 2021). In general, low stocking densities is related to improvement in growth performance and survival rates of fish.…”

A review on recirculating aquaculture system: influence of stocking density on fish and crustacean behavior, growth performance, and immunity

“…Larval stages are more sensitive to stocking densities compared to later stages of the fish life cycle. Previous studies have shown increased cannibalism, reduced feed intake, and poor growth performance among larvae of several fish species reared under high stocking densities (de Barros et al, 2019;Santos et al, 2020;Slembrouck et al, 2009;Sukumaran et al, 2011). Furthermore, manipulation of rearing conditions such as feeding regimes, feed composition, water salinity, and light spectrum among others could influence changes in the recommended optimal stocking densities required for the species' survival and performance.…”

“…Santos et al (2020) investigated the influence of different stocking densities (10, 30, and 50 larvae/L) on the survival and growth performance of C. macropomum larvae reared in slightly saline RAS for 30 days. The authors recommended that larvae of C. macropomum can be successfully reared in slightly saline RAS at stocking densities of up to 50 larvae/L.In another study, de Souza e Silva et al (2021) found better survival, growth, and stress resistance in C. macropomum juveniles (initial weight 0.35 ± 0.10 g) at stocking densities of between 3 and 5 animals/L.…”