Product quality, fish welfare and salmon louse infestation of Atlantic salmon and rainbow trout fed a diet supplemented with fermented soybean and macro algae (Saccharina latissima)

• Main Author: Formanowicz, Julia
• Other Authors: Mørkøre, Turid
• Format: Master Thesis
• Language: English
• Published: Norwegian University of Life Sciences, Ås 2022
• Subjects: Atlantic salmon; Salmo salar
• Online Access: https://hdl.handle.net/11250/3041921

Aquaculture is an expanding industry that is expected to grow furthermore (FAO, 2020). The expansion leads to a demand of sustainable feed ingredients that are limited today. Atlantic salmon (Salmo salar L.) and rainbow trout (Oncorhynchus mykiss) fed with commercial control feed or the same feed with inclusion of fermented soybean and macro algae, Saccharina latissima (test feed, macro algae) were farmed at commercial farming locations at the Norwegian West coast for 13 and 6 months, respectively. The effect of feed on product quality, fish welfare and salmon louse infestation were investigated. Results of this trial showed improved growth of salmon fed test feed, resulting in a 19% higher body weight at harvest (6.6 kg vs. 5.5 kg). The body weight of the rainbow trout fed test feed was 6.5% lower compared with the control feed (3.1 kg vs. 3.4 kg). The test feed had no positive effect on fillet colour or texture but gaping and scale loss were lower in salmon. Salmon fed with control feed or feed with inclusion of macro algae had similar development in biometric traits. There was similar development in salmon louse number in Atlantic salmon, while in rainbow trout there was a trend showing lower salmon louse number in fish fed with test feed compared to fish fed with control feed. Akvakultur er en ekspanderende næring som forventes å vokse ytterligere (FAO, 2020). Utvidelsen fører til en etterspørsel etter bærekraftige fôrråvarer som er begrenset i dag. Atlantisk laks (Salmo salar L.) og regnbueørret (Oncorhychus mykiss) fôret med kommersielt kontrollfôr eller samme fôr med tilskudd av fermentert soyabønner og makroalger, Saccharina latissima (testfôr, makroalger) ble oppdrettet på kommersielle oppdrettsanlegg langs den norske vestlandskysten i henholdsvis 13 og 6 måneder. Effekten av fôr på produktkvalitet, fiskevelferd og luseinfestasjon ble undersøkt. Resultatene fra dette forsøket viste forbedret vekst av laks fôret med testfôr, noe som resulterte i 19% høyere rundvekt ved slakt (6.6 kg vs. 5.5 kg). ...