Effect of feeding frequency as a rearing system on biological performance, survival, body chemical composition and economic efficiency of Asian seabass Lates calcarifer (Bloch, 1790) reared under controlled environmental conditions

Abstract

A 70-day rearing trial was done to determine the optimal frequency of feeding on growth performance (GP), feed conversion rate (FCR), cannibalism, survival rate (SR), body chemical composition and economic efficiency of the Asian sea bass. This study tested four different treatments of feeding frequencies (FF), once (T1), twice (T2), three times (T3), and four times (T4) per day. An average initial weight of Asian sea bass fry was 0.2 g (SD = ±0.12) were stocked 10 individuals per m 3 (9.14 m × 1.82 m × 1.22 m, L × W × H; water depth 0.61 m) with two replicates per treatment (4 × 2 = 8). Fry were fed a mixture of larval commercial feed and shrimp with a pellet diet containing (46% CP). Initially, the feeding rate of 8% biomass per day was further adjusted according to fish biomass on a weekly basis. Results showed that, the FF significantly affected ( p < 0.05) on growth indictors and survival rate (SR). Specifically fry fed three times a day (T3) had the best FBW, FL, SGR, ADWG and FCR followed by T4 and T2 while fry fed one time a day was the lowest in these parameters. Also, VSI, HSI and CF (k) significantly differed among the treatments. The fish whole body content of protein, moisture and ash did not significantly ( p < 0.05) be affected by feeding frequency, but lipid content differed and both T3, T4 were the highest. It could be concluded that, increasing FF up to three times a day had a positive effect on weight gain, survival rate and feed utilization of Lates calcarifer . The second degree polynomial regression indicates that fed three times a day is optimum for best growth performance and survival for Asian sea bass.

Growth performance, haematological assessment and chemical composition of Nile tilapia, Oreochromis niloticus (Linnaeus, 1758) fed different levels of Aloe vera extract as feed additives in a closed aquaculture system

“…Sampling was performed weekly. At the time of each sample, the fish growth parameters were calculated ( Makori et al, 2017 , Hassan et al, 2020 , Hassan et al, 2021c ). Indices for the evaluation of growth performance have been determined as follows:…”

An investigation on protein and amino acid contents in scales and muscles of pomfret Parastromateus niger (Bloch, 1795) and Pampus argenteus (Eupharasen, 1788)

“…The composition of amino acids in scales and muscles was measured by the ion-exchange liquid chromatography method followed by the Association of Official Analytical Chemists (AOAC, 2005) and Masood et al (2015a,b). Finally, the statistical analysis of data was tested by using MS Excel and SPSS (Hassan et al, 2021a) statistical software.…”

Growth performance and survivability of the Asian seabass Lates calcarifer (Bloch, 1790) reared under hyper-saline, hypo-saline and freshwater environments in a closed aquaculture system

“…Asian seabass can be reached to 1.5 to 3.0 kg in a year when its environmental conditions are optimum, and the maximum weight has been recorded about 60 kg . Asian seabass has sustained high demand and market price in domestic and export markets (Rao et al, 2013;Hassan et al, 2021b). Asian seabass is a hardy species that tolerates a broad salinity range from 0 to 56 ppt salinity (FAO, 2017).…”