One of the main challenges of modern Aquaculture is reducing the use of Fish Meal and Fish Oil on fish feed by introducing new ingredients and maintaining the quality of feeds as well as the performance and welfare of fish.
DIBAQ, following its innovative policy and with the aim to produce more sustainable and functional feeds, carried out the project FISHUB, funded by APROMAR (Spanish Aquaculture Corporate Association).
The main goal of the project It’s been to develop new functional diets, more sustainable and with a high productive and immune performance in aquatic species by introducing, in commercial formulas, fermented soybean meal.
To that end, we carried out three trials with three of the main commercial species of the medietrranean aquaculture such as Sole (Solea solea), Seabream (Sparus aurata) and Seabass (Dicentrarchus labrax).
Each trial were 18 weeks long. We tested a control diet (Diet B) versus two experimental diets replacing fish meal with different inclusion levels of fermented soybean meal (Diet A 50% inclusion and Diet C 25% inclusion). Always tried to keep the control nutritional profile on diets A and C; same protein profile and same fatty acids profile (EPA & DHA).
These trials showed similar results, both in nutritional and immune trials, for the three species. No significant statistical differences were found but for control diet and high inclusion of fermented soybean diet that showed a minimum slight difference in performance with better results.
| Dieta A | Dieta B | Dieta C | P valor | |
| Peso inicial (g/ind) | 30,94±0,80 | 29,95±0,4 | 30,34±0,88 | 0,090 |
| Peso final (g/ind) | 103,65±4,13 | 104,21±3,72 | 102,18±2,78 | 0,609 |
| Incremento de peso (g) | 72,72±3,46 | 74,26±3,7 | 71,84±2,33 | 0,439 |
| SGR (%/día) | 1,44 ± 0,03 | 1,48 ± 0,04 | 1,45 ± 0,03 | 0,134 |
| FCR | 1,52 ± 0,06 ab | 1,49 ± 0,05 a | 1,58 ± 0,04 b | 0,015 |
| k | 2,93± 0,05 | 2,86 ± 0,08 | 2,93 ± 0,05 | 0,171 |
| Supervivencia (%) | 97,78 ± 2,72 | 98,33 ± 1,83 | 98,89 ± 1,72 | 0,734 |
| Índice Hepatosomático | 2,10± 0,2 | 1,95 ± 0,22 | 2,33 ± 0,63 | 0,367 |
| Ingesta total de alimento (g) | 3287,25 ± 194,62 | 3282,92 ± 115,50 | 3391,78 ± 92,54 | 0,345 |
Table 7: Performance data for Sea Bream
Nota: SGR = Specific Growth Rate; FCR= Feed Conversion Rate; K= Fulton’s condition factor.
Results of pathological challenge carried out in Seabass against the bacteria Photobacterium damselae subsp. Piscicida, also showed no significant differences between three diets but for a slight worst performance on diet with less inclusion level of fermented soybean meal.
Figura 4. Cumulative Mortality fo Diets A, B & C. during the Challenge.
As conclusion, showing the three trials results, referring performance rates, optimum growing rates, and normal range of conversion rates, replacing fish meal in commercial diets with fermented soybean meal could have a positive impact on feed manufacturing, keeping performances on good levels without damaging fish immune and welfare condition.
