Sexual maturation of male Atlantic salmon post‐smolts (‘jacking’) is undesired in aquaculture and seems to occur due to the intensification in modern facilities. Maturation depends on internal and external factors (temperature, photoperiod, feed availability, energy levels, body size, genetic background) that act on the brain‐pituitary‐gonad axis to trigger maturation. This study assessed the influence that the body weight at...

The transfer time of Atlantic salmon smolts from freshwater to seawater remains a challenge in aquaculture, with the “smolt window” referring to the optimal timeframe for seawater readiness. Our study monitored Atlantic salmon osmoregulatory adaptations during smoltification under continuous light (LL) and winter signal regime (6 weeks LD 12:12) followed by 6 or 8 weeks of constant light. Fish were subsequently reared in seawa...

Acoustic lice treatment (AcuLice) is a newly developed system which uses a composite acoustic sound image with low-frequency sound to remove salmon lice (Lepeophtheirus salmonis) from Atlantic salmon (Salmo salar). The effect of AcuLice treatment on salmon lice dynamics was measured by weekly salmon lice counting at a full-scale production facility from mid-summer 2019 to late-spring 2024. We monitored four production cycles,...

Sexual maturation of post-smolts is a concern for Atlantic salmon producers, and its occurrence is dependent upon factors such as water temperature and energy availability, among others. The present study was designed to investigate the effect of different temperatures and feeding regimes on testis development and local regulation of spermatogenesis in salmon post-smolts. A 3 × 2 factorial design was used, with three temperatu...

Acoustic lice treatment (AcuLice) is a newly developed system, which uses a composite acoustic sound image with low-frequency sound to remove salmon lice (Lepeophtheirus salmonis) from Atlantic salmon (Salmo salar). This field study documents the stress effects on Atlantic salmon and the effect on salmon lice dynamics during large-scale use of the AcuLice system. The effect of the AcuLice treatment on salmon lice dynamics was...

The use of closed containment (CCS) or semi‐closed containment systems (S‐CCS) for Atlantic salmon Salmo salar aquaculture is under evaluation in Norway. One such system is the Preline S‐CCS, a floating raceway system that pumps water from 35 m depth creating a constant current through the system. Exposing fish to moderate water currents is considered aerobic exercise and it is often perceived as positive for fish welfare, gro...