Dietary protein requirement in common snook (Centropomus undecimalis ) juveniles reared in marine and brackish water

Abstract

A total of 300 Centropomus undecimalis juveniles, with an average initial weight of 3.16 0.28 g and average total length of 7.17 0.22 cm, were reared for eight weeks using a recirculating system to determine the dietary protein requirement for their growth and survival. The eect of ve experimental diets containing 40, 45, 50, 55 and 60% total protein content and two salinities (brackish water, BW at 5 UPS and marine water, MW at 36 UPS) were assessed. Fish were fed ve times per day at 2.5% of total biomass. All treatments were performed in triplicate,recording the individual weight and total length every 15 d, while weight gain and daily growth rate were recorded at the end of the experiment. Mean weight increased proportionally as protein content increased, with the greatest growth occurring with a 60% protein diet for sh reared in brackish water, and 55% for sh in marine water. We consider that the protein requirement in C. undecimalisjuveniles is high; in addition, it differs depending on the salinity, </

The optimal dietary protein level of juvenile silver sillago Sillago sihama at three dietary lipid levels

“…Besides, higher DPs of 500 and 550 g/kg markedly decreased the PER than it in 450 g/kg level. The decreased trend of PER at higher DP was similar to the result reported by Bartolo et al (). It was reported that an excess of proteins could stimulate increased trypsin production, which increased both satiety and energy costs used for ammonia excretion (Bartolo et al, ).…”

“…lanceolatus (Rahimnejad et al, ); 480 g/kg and 120–150 g/kg for juvenile northern snakehead fish, Channa argus (Sagada et al, ); 550 g/kg and 70 g/kg for golden mandarin fish, Siniperca scherzeri (Sankian et al, ); 450 g/kg and 50 g/kg for Pseudobagrus ussuriensis fingerlings (Wang et al, ); and 400 g/kg and 80 g/kg for juvenile goldfish, Carassius auratu (Belsare et al, ). The observed differences of required DP and DL could be due to factors such as different species and size, protein and lipid sources, amino acids composition, water temperature, environmental condition, rearing system, non‐protein energy sources and level (Bartolo et al, ; Henry & Fountoulaki, ; Ng et al, ; Rahimnejad et al, ).…”

Physiological and metabolic protein‐sparing effects of dietary lipids on common snookCentropomus undecimalis(Bloch, 1792) juveniles

“…These data suggest that a dietary protein level of 400 g kg −1 with 120 g kg −1 lipid could meet the needs for optimal growth of the common snook. However, Concha‐Frías et al (2018) previously observed relatively lower growth (based on SGR) in common snook (3.15 g initial weight) fed 400 g kg −1 protein with 151 g kg −1 lipid and 300 g kg −1 wheat and corn meal, compared to 500 g kg −1 protein with 154 g kg −1 lipid and 140 g kg −1 wheat and corn meal. The differences between studies could have been attributed to those in dietary formulation, particularly digestible carbohydrate inclusion as a dietary non‐protein energy source, which were supplied in a minimal percentage in the test diets of this study (20 g kg −1 corn starch).…”

“…Liver enzyme assays were monitored spectrophotometrically by observing changes in the absorbance of NADH/NAD and NADP/NADPH per min at 340 nm for 10 min (Borrebaek et al, 1993; Tranulis et al, 1996). All enzyme activities were measured at 37°C (Bonamusa et al, 1992; Concha‐Frías et al, 2018; Gjellesvik et al, 1992). Digestive and metabolic enzyme activities were reported as mg of soluble protein (specific activity).…”

“…Common snooks have the advantages of fast growth (Tucker, 1987) and low feed conversion ratio (Alvarez‐Lajonchère & Ibarra‐Castro, 2013) and they mature and spawn in captivity (Ibarra‐Castro et al, 2011). Regarding the nutritional requirements, previous reports have revealed that common snook has a protein requirement in the diet of 500 g kg −1 (Concha‐Frías et al, 2018; Gracia‐López et al, 2003; Tucker, 1987). Additionally, in a recent study, Lemus et al (2018) proposed a selection of marine and terrestrial ingredients as an alternative source to fishmeal protein for common snook feeds.…”