PENGARUH APLIKASI RECIRCULATING AQUACULTURE SYSTEM DAN SISTEM HIBRID RECIRCULATING AQUACULTURE SYSTEM-ZERO WATER DISCHARGE SERTA SUPLEMENTASI PAKAN SINBIOTIK TERHADAP PERFORMA PERTUMBUHAN DAN PROFIL KOMUNITAS MIKROBA IKAN NILA (OREOCHROMIS NILOTICUS L.)

• Main Author: Nurwahyuni, Risa
• Format: Final Project
• Language: Indonesia
• Subjects: Ilmu hayati ; Biologi
• Online Access: https://digilib.itb.ac.id/gdl/view/54875
• Institution: Institut Teknologi Bandung

Nile tilapia (Oreochromis niloticus L.) is one of the freshwater fish commodities with the highest production level in Indonesia. Tilapia aquaculture in Indonesia is still dominated by conventional open systems (flow-through) whose productivity is often difficult to predict. The Zero-water Discharge / ZWD system is an alternative to closed aquaculture systems that can improve cultivation performance through manipulation of water microbes, but its application cannot be done for a long cultivation period. Apart from ZWD, the Recirculating Aquaculture System / RAS closed system can also improve the performance of tilapia aquaculture. However, high operational costs and lack of microbial control are the limitations of RAS. In addition, the application of functional feed with synbiotic supplementation, namely a mixture of probiotics and prebiotics, is also an alternative health management strategy for tilapia. This study aimed to compare the application of RAS-ZWD hybrids with RAS, as well as RAS with and without synbiotic feed supplementation on growth parameters and profiles of gut microbial communities and tilapia cultured water. This research began with the preparation of a culture system and the production of synbiotic feed (a consortium mixture of probiotics and microalgae Spirulina platensis powder). Furthermore, tilapia rearing was carried out in two test stages: (1) comparison of the RAS-ZWD ('RH') hybrid system with RAS (control / 'K') both of which were given commercial feed, and (2) comparison of RAS with synbiotic feed ('RS') with RAS with commercial feed (control / 'K'). Analysis of fish growth and also gut and cultured water microbial community profiles were carried out for 60 days of rearing using a culture-dependent method. The results showed that K produced an average daily growth (1.08 ± 0.14 gr / day), final body weight (81.42 ± 2.46 gr), total biomass (1.68 ± 0.08 kg), and productivity (16.80 ± 0.78 kg / m3) which were significantly higher for RH (P <0.05). Furthermore, the RS produced average daily growth (1.24 ± 0.11 gr / day), final body weight (87.28 ± 4.95 g), total biomass (1.74 ± 0.13 kg), efficiency feed (1.04 ± 0.05), as well as productivity (17.43 ± 1.27 kg / m3) were higher, but not significantly different compared to K (P> 0.05). The water quality parameters of RH, K, and RS during the rearing period were within the tolerance range for tilapia. However, the pH range, as well as the ammonium and nitrite levels at K were better than RH. The ammonium range at K was also better than that of RS. In addition, the analysis of microbial community profiles showed that the total heterotrophic bacteria in the water and fish gut at RH and RS were higher than K. Total Vibrio in the water and fish gut of the three treatments were below the lethal threshold. The values of diversity, stability and dominance of the water and fish gut microbial communities in the three treatments fluctuated throughout the rearing process. In general, it could be concluded that the use of RAS could significantly improve the performance of tilapia aquaculture compared to the RAS-ZWD hybrid. However, the performance of microbiological parameters was better for the RAS-ZWD hybrid than in the RAS. The use of RAS with or without synbiotic feed supplementation was able to improve the growth performance of tilapia, but further technical and economic feasibility studies are needed for application on a field scale.