Effect of Supplementation of Dried Bioflocs Produced by Freeze-Drying and Oven-Drying Methods on Water Quality, Growth Performance and Proximate Composition of Red Hybrid Tilapia

Tarq Binalshikh-Abubkr,Marlia Mohd Hanafiah

doi:10.3390/jmse10010061

Abstract

Supplementation of dried bioflocs for red hybrid tilapia (Oreochromis sp.) was examined during 57 days of feeding trials. Five experimental treatments; T1 (the control; without bioflocs), T2 (4% freeze-dried bioflocs), T3 (16% freeze-dried bioflocs), T4 (4% oven-dried bioflocs), and T5 (16% oven-dried bioflocs) were prepared to examine the water quality, growth performance and body composition of red hybrid tilapia. T2 and T4 treatments resulted in a higher growth rate and survival similar to the control, while T3 and T5 treatments showed the lowest values of growth performance among all treatments. T1 treatment showed the best quality of culture water followed by T2 and T4 treatments, while T3 treatment resulted in poor water quality followed by T5 treatment. Based on these results, the ratios of bioflocs (4% and 16%) had more effect on fish growth and water quality than the drying methods (freeze-drying and oven-drying). The ratio of 4% freeze-dried or oven-dried bioflocs provided higher growth rates and better water quality parameters similar to the control, while the ratio of 16% showed the worst growth performance and water quality in the present study. In addition, body compositions of tilapia fed 4% dried bioflocs showed better nutritional value than tilapia fed 16% dried bioflocs. Protein and energy levels showed an increasing trend with decreasing supplement levels of bioflocs. Moisture content was significantly higher when supplementation of 16% bioflocs was used. Overall, supplementation of 4% freeze-dried or oven-dried bioflocs can be successively included in red hybrid tilapia diets without any effects on growth or body composition and can result in a good quality of culture water for red hybrid tilapia.

Highlights

In the recent past, feed expenses have become an urgent issue for the aquaculture sector because of the high cost of feed ingredients and the continually increasing of using of animal or plant origin as a protein source in aquafeeds to meet nutritional requirements for fish feed [1,2]
T2 treatment was significantly higher compared to T1 and T4 treatments in terms of chemical oxygen demand (COD), while T3 treatment showed higher values of Biological oxygen demand (BOD) and COD than T5 treatment
Our results showed that a ratio of 4% freeze-dried and/or oven-dried bioflocs provided higher growth rates similar to the control (100% commercial feed), while the ratio of 16% freeze-dried and/or oven-dried bioflocs showed a loss in growth rate for tilapia

Summary

Introduction

In the recent past, feed expenses have become an urgent issue for the aquaculture sector because of the high cost of feed ingredients and the continually increasing of using of animal or plant origin (such as fishmeal and soybean meal) as a protein source in aquafeeds to meet nutritional requirements for fish feed [1,2]. Bioflocs can be collected from biofloc technology (BFT) system as a wet meal to culture animals [11,12] or as a dried meal after drying processes with high protein levels [13,14,15]. The technology as well as the use of bioflocs meal as a supplement or replacement of a part of expensive feed ingredients (fish meal and fish oil) is very promising to minimize feed costs and maximize farm profits

Methods

Results

Discussion

Conclusion