Research Article Alemayehu and Getahun, J Aquac Res Development 2017, 8:4 DOI: 10.4172/2155-9546.1000479 Research Article Open Access Journal of Aquaculture Research & Development J o u r n a l o f A q u a c u lt u r e R e s e a r c h & D e v e l o p m e n t ISSN: 2155-9546 Volume 8 • Issue 4 • 1000479 J Aquac Res Development, an open access journal ISSN: 2155-9546 Keywords: Cage culture; Feeding frequency; Growth performance; Oreochromis niloticus; Survival Introduction Diet supplementation and selection of appropriate species for culturing environment are important criteria in aquaculture. Nile tilapia (Oreochromis niloticus) is a widely-cultured species all over the world [1-3], as it is easily spawned, tolerance to handling, and resistance to disease, efcient conversion of natural and prepared feeds, controllable reproduction, good marketability, tolerates poor water quality and grows rapidly at warm temperature [3-5]. Since the feed cost accounts approximately 50% of the operating costs in intensive culture systems [4,5], the economic viability of the culture operation depends on appropriate use of feed [6]. Nutrition is one of the most important factors infuencing performance of cultured fsh and is infuenced by factors such as behaviour of fsh, stocking density, quality of feed, daily ration size, feeding frequency and water temperature. Feeding frequency mainly depends on species cultured, age, size, feed quality and environmental factors [5,7-11]. Tese characters of species and environmental factors infuence gastric evacuation time (return of appetite) of cultured organisms and gastric evacuation time of cultured organism on the other hand infuences feeding frequency [12]. De Silva and Anderson [7], Tran et al. [13] and Malcolm et al. [14] reported that determining optimum ration size and feeding frequency is an important step in aquaculture operation since they are important to ensure maximal Feed Conversion Ratio (FCR) of cultured organism. Several researches were carried out on efects of feeding frequency on growth of diferent fsh species at diferent life stages, environmental conditions and culture conditions; but optimal feeding frequency is highly variable from species to species [15-22]. On the other hand, there is little information about optimum feeding frequency of farmed O. niloticus. Terefore, the aim of this study was to investigate efect of feeding frequency on growth performance and survival of O. niloticus. Materials and Methods Study site and experimental design Te study was conducted in Lake Hora-Arsedi, one of the Crater Lakes in Ethiopia and located at altitude of 1850 m asl and 8º 46'' N and, 38º 59'' E, is 45 km southeast of Addis Ababa (the capital of Ethiopia). Te jetty was constructed from wood (eucalyptus) (at site 1) which is perpendicular to the water current [4,23-25]. It has an average depth between 6-7 m, 25 m length and 1m width, which is 7 meter away from the shore. Te control site (site 2) was selected to sample plankton and for measuring physical parameters and compare that with the experimental site. Cages with the size of 1 m 3 (1m × 1m × 1m) were constructed from frame (PVC type 50, tube of 10 cm with 1 mm polyethylene material) and the enclosure nylon netting material with mesh size of 4 mm as an enclosure material. Te cages were placed side by side in rows under the jetty with equal interval (0.75 meter apart). Mixed sex juveniles of O. niloticus were collected from Lake Hora- Arsedi using beach seine hauls 50 m × 2.5 m (with stretching mesh size of 20 mm). Immediately afer screening, the fngerlings were transported to experimental cages by plastic barrel half-flled with lake water. Te total length (TL. by measuring board) and total weight (TW. digital balance) were measured and fngerlings with length 115 *Corresponding author: Tewodros Abate Alemayehu, Department of Biology, Debre Berhan University, Debre Berhan, P. O. Box 445, Ethiopia, Tel: 0912213468; E-mail: ttabate@gmail.com Received May 22, 2016; Accepted May 08, 2017; Published May 10, 2017 Citation: Alemayehu TA, Getahun A (2017) Effect of Feeding Frequency on Growth Performance and Survival of Nile Tilapia (Oreochromis niloticus L. 1758) in a Cage Culture System in Lake Hora-Arsedi, Ethiopia. J Aquac Res Development 8: 479. doi: 10.4172/2155-9546.1000479 Copyright: © 2017 Alemayehu TA, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Abstract In this study, the growth performance and survival rate of Nile tilapia (Oreochromis niloticus) subjected to different feeding frequencies were evaluated in cage culture. Juveniles with mean initial weight of 35.99 ± 0.23g were stocked in 1 m 3 net cages and assigned to a duplicate of 50 fsh in a completely randomized design in six treatments. T1 were fed 3% of their body weight divided into four equal meals per day for the frst three months and then allowed to feed two times a day for the next three months; T2 and T3 were fed 3% of their body weight divided equally at frequency of four and two feedings/day, respectively, throughout the experiment. Feed was given once a day (without dividing) for T4 and once every other day (without dividing) for T5 throughout the experiment. All treatments were fed pelleted diet except the control groups in which fsh were provided with only the natural food. The mean specifc growth rates (SGR), Feed conversion ratio (FCR) and Feed conversion effciency (FCE) were statistically similar for T1 and T2, but they were higher than T3, T4 and T5. However, mean weight gain, mean daily gain and Condition Factor (CF) showed a signifcant difference (P<0.05) among experimental groups. In conclusion, growth performance and net yield were increased with increased feeding frequency, so frequent feeding was recommended for optimum result of O. niloticus in cage culture. It was also revealed that cage culture at experimental level has no effect on the water quality and plankton abundance. Effect of Feeding Frequency on Growth Performance and Survival of Nile Tilapia (Oreochromis niloticus L. 1758) in a Cage Culture System in Lake Hora-Arsedi, Ethiopia Tewodros Abate Alemayehu 1 * and Ababe Getahun 2 1 Debre Berhan University, Department of Biology, Debre Berhan, Ethiopia 2 Department of Zoological science, Faculty of Life Science, Addis Ababa University, Addis Ababa, Ethiopia