Potential of Insect-Based Diets for Atlantic Salmon
Atlantic salmon, a ray-finned fish that is found in northern Atlantic Ocean and rivers that flow through Atlantic. These are the largest species in their genus ranging from 71cm-76 cm in length. Young salmon spend up to four years in the natal river and slowly move out after into the ocean. It will then change in color from stream adapted gray spots to sea adapted shiny sides. The study aimed to assess the effects of insects and insect oils on the dietary meal of Atlantic reared salmon. Since the global consumption of salmon fish are of highly in demand. So, to meet these growing needs an increased of production efficiency of aquaculture is needed. While maintaining the environmental sustainability, the choice of ingredients on fish diet can greatly influence environmental impacts.
Diets of Atlantic Salmon
The growth performance, body composition and nutrient digestibility of Atlantic salmon were assessed. The insect and insect oil produced by black soldier flies were introduced as food diets for 8 weeks. Replacing dietary fish meal with insect proteins reveals significant results on digestibility coefficients of protein, lipids and amino acids. It also shows that inclusion of insect meal diets increased the hepatosomatic index and visceral somatic index of Atlantic salmon. Furthermore, fish feeds with insect did not affect voluntary intake, indicating that no negative effect on palatability of Atlantic salmon.
On the other hand fish feed with insect oil from larvae grown on substrate enriched with marine macroalgae grew fast. Compared to the fish fed with insect oil from larvae that grown on media with terrestrial organic waste. Indeed, inclusion of marine brown algae improved nutritional composition of the black soldier flies larvae grown on feeding media. Therefore, marine nutrients are especially beneficial for the growth of marine carnivore fish species.
Indeed, the study shows that insect meal and oil from black soldier flies larvae hold great potential as nutrients source. It also demonstrates that there is no adverse effect on growth, feed utilization, digestibility and body composition of Atlantic salmon. Moreover, protein efficiency ratio and whole body crude protein were unaffected by insect meal diets. So, it indicates that insect meal can be utilized efficiently as protein source of Atlantic salmon.
Source: Prepared by Joan Tura from the Journal of Aquaculture
Volume 491, 1 April 2018, Pages 72-81