Culture of the Nile tilapia (Oreochromis niloticus) in a recirculating water system using different protein levels

Abstract

ABSTRACThe study investigated the effect of dietary protein levels on growth performance and body composition of the Nile tilapia, Oreochromis niloticus fingerlings (8.0 g), using a recirculating water system. The system consisted of eight rearing concrete tanks, underground plastic tank acts as a clarifier and upper plastic tank acts as a biofilter. The system was supplied with air and water pumps. Fish were fed on four dietary protein levels (20%, 25%, 30% and 35%) to satiaty for 6 days a week for 6 months. Results showed that fish growth was significantly affected by protein level. Fish fed on 30% protein diet attained the highest growth (higher weight gain, higher daily weight gain and higher specific growth rate). The best food conversion ratio (FCR) (2.05) was obtained by 30% protein diet, while the poorest FCR (2.72) was obtained by 20% protein diet. Protein efficiency ratio (PER) was significantly affected by protein levels. It decreased with increasing protein level. Results of body composition showed that protein and lipid contents were significantly affected by protein level. Protein content was significantly increased with increasing protein level in the diet. In contrast, lipid content was inversely affected by increasing the dietary protein level. The study showed that the recirculating water system is suitable for Nile tilapia culture in Egypt, and that a diet containing 30% crude protein is economical and suitable for Nile tilapia fingerlings feeding.

Analysis of hematologic alterations, immune responses and metallothionein gene expression in Nile tilapia (Oreochromis niloticus) exposed to silver nanoparticles

“…Nile tilapia (Oreochromis niloticus) is an economically important aquatic animal cultured worldwide. Its rapid growth rate, adaptability to a wide range of environmental conditions and ability to grow at low trophic levels make it an excellent candidate for aquaculture, especially in tropical and subtropical regions, including Thailand (Bahnasawy et al 2009). Nile tilapia are capable of adaptation to various habitats and may be a good representative of aquatic animals for studying the impact of polluting toxicants, like AgNP, on local animal health.…”

Growth and Body Development of Oreochromis niloticus (Linnaeus, 1758) Fattened in Floating Cages Based on Commercial Feed in Benin

“…The PER of this study (1.62 ± 0.06) is in the interval from 1.25 to 1.98 reported by Khattab et al (2000) for Nile tilapia in pond culture. It is also between the range of 1.34 to 1.85 reported for O. niloticus reared in recirculating water system, using feed containing respectively 35% and 20% crude protein content at a stocking density of 60 fish/m 3 (Bahnasawy et al, 2009). Ahmad et al (2004) found PER of 1.92; 1.58 and 1.98 for tilapia fingerlings (20.3 g) reared in concrete tanks using a recirculating system and a diet containing 25; 35 and 45% crude protein respectively.…”

“…Protein efficiency ratio (PER) is based on the weight gain of a test subject divided by its intake of a particular food protein during the test period (Buamah and Singsen, 1975). According to Bahnasawy et al (2009), fish growth is significantly affected by diet protein level. The PER of this study (1.62 ± 0.06) is in the interval from 1.25 to 1.98 reported by Khattab et al (2000) for Nile tilapia in pond culture.…”

A Preliminary Study on Oxya fuscovittata (Marschall) as an Alternative Nutrient Supplement in the Diets of Poecillia sphenops (Valenciennes)

“…However, dissolved oxygen is a little lower than the optimum need (i.e. above 5 mg/L) for most of the fishes [15], [16]. The main cause behind this lower DO may be because no aerator is used in the tanks.…”