Gutenborn, Germany (August 01, 2016) – The culture of sea bass and seabream is an important production sector in the Mediterranean Sea, and these species combined represent the largest volume of aquaculture production in the region (134,978 tons of European sea bass and 138,694 tons of gilthead seabream were produced in the Mediterranean Sea in 2012).
The objective of the trial what to evaluate the efficiency of functional feed Sanbio MARE added to normal diets for sea bream (Pagrus major) fed compared to similar diets but without addition of Sanbio MARE. The trial was performed according to the Best Practice Guideline by targeting the sensitive parameter (mortality, weight gain, feed intake, feed conversion rate).
The SANBOS GmbH, in cooperation with local partners, conducted a tank feeding trial with sea bream (Pagrus major). The objective of the trial was to demonstrate Sea Bream growth and performance in fresh-water tanks with a partial replacement of fish feed by the functional feed Sanbio MARE.
1. Materials and methods
Four cages of average size 8 m3 (underwater volume) at the cage fish farm were used for the feeding trial. Cages were constructed of nylon netting over a rigid cage frame and were individually fitted with an opaque cover and a feed enclosure to contain extruded, floating and slowly sinking feed pellets. Cage placement was at the perimeter of the cage farm, with a minimum spacing of two meters between and on all sides of each cage.
Fish were 262 g Red Sea Bream produced locally. Sea bream were stocked in the four trial cages on 31 March at a density of 1,000 fish per cage. Fish in all four trial cages were of uniform size, age and health status at stocking. Target market size for sea bream was 500 g per fish in a 180-day production cycle.
Sea bream in the control cage were fed with 100% of standard marine growout feed in extruded, floating pellet form as per Table 1.
Sea bream in treated trial cages were fed with 80% of standard marine growout feed in extruded, floating pellet form as per Table 1 and 20% of Sanbio MARE as per Table 2.
Fish were fed to satiation twice daily, with fish in all four cages fed identically at every feeding. Feed pellet size was increased as the fish grew so that the maximum size pellet that all fish could consume was being fed. Trial management was based on the best practice and Sanbos standards. Fish in all cages were sampled once per month on approximately the same date each month.
At the conclusion of the trial, all cages were emptied and the fish in each cage counted and weighed to determine average fish weight, gross and net production, feed conversion ratio (FCR) and survival. Production input costs were recorded throughout the trial and net income and return on investment (ROI) were calculated at the end of the trial.
Table 1. Formula for the standard fish feed used in the trial
| Pellet size (mm) | 3 / 4.5 / 6 |
| Crude protein (%) | 42 |
| Crude fat (%) | 21 |
| NFE (%) | 20 |
| Ash (%) | 6.5 |
| Fibre (%) | 2.5 |
| P (%) | 1 |
| Gross energy (MJ) | 22.1 |
| Digestible energy (MJ) | 18.8 |
Table 2. Formula for the “Sanbio SANA” fish feed supplement used in the trial
| Pellet size (mm) | 3 / 6 |
| Crude protein (%) | 40 |
| Crude fat (%) | 10 |
| Ash (%) | 8 |
| Fibre (%) | 4.7 |
| P (%) | 1.5 |
| Amino acids | 5 |
| Vitamins | 1 |
| Carbohydrates | 5 |
| Minerals | 5 |
| Formate | 2.5 |
| Gross energy (MJ) | 22 |
| Digestible energy (MJ) | 18 |
2. Results
Red sea breams were fed a total of 117 days between 31 March and 25 July 2016. Sea breams grew from 261 g to an average weight of 1072 g (+15% compared to control) during this feeding period. Gross production averaged 728.95 kg per cage (+20% compared to control).
Average sea bream survival rate was 69.87% (+8,6% compared to control). Average FCR for sea bream was 2.93 (-14% compared to control).
Table 3. Productive performance
| Cage no. | Unit | 1 | 2 | 3 | 4 | Average 2/3/4 |
| Cage | Control | Trial 1 | Trial 2 | Trial 3 | ||
| No day fed | D | 117 | 117 | 117 | 117 | |
| Stocking rate | Fish/tank | 1000 | 1000 | 1000 | 1000 | 1000.00 |
| Harvest rate | Fish/tank | 648 | 682 | 718 | 696 | 698.67 |
| Mortality | % | 35.2 | 31.8 | 28.2 | 30.4 | 30.13 |
| Survival | % | 64.8 | 68.2 | 71.8 | 69.6 | 69.87 |
| Fish stocking weight | g | 262 | 263 | 261 | 259 | 261 |
| Fish harvest weight | g | 941 | 1023 | 1031 | 1076 | 1043 |
| Weight gain | g | 679 | 760 | 770 | 817 | 782.3 |
| Specific growth rate | SGR | 1.09 | 1.16 | 1.17 | 1.22 | 1.18 |
| Production | kg/tank | 609.8 | 697.7 | 740.3 | 748.9 | 728.95 |
| kg/m3 | 76.2 | 87.2 | 92.5 | 93.6 | 91.12 | |
| Feed intake | kg/tank | 2073 | 2163 | 2073 | 2172 | 2135.78 |
| FCR | 3.4 | 3.1 | 2.8 | 2.9 | 2.93 |
Figure 1. Productive performance (%)
3. Conclusion
To summarize, the present study shows significantly positive effects of SANBIO MARE at the dosage of 20% of diet on productivity.
The positive effects at a glance:
- Reduction of mortality
- Increase of weight gain
- Improvement of FCR
- Positive effects on health status
- Safety and tolerance when used dietary additions.