Fish health is one of Skretting’s main lines of action. The company performed a trial to evaluate the effectiveness of the Protec feed line against the retraction of the operculum in Atlantic salmon during its initial stages of culture.

“Skretting's focus is the maintenance of good fish health. The operculum, in addition to playing a fundamental role in the respiration of fish, also protects the gills, that, when unprotected, cause different problems increasing fish stress and susceptibility to contracting pathogens,” said Charles Booth, freshwater product manager and author of the study. The company reported an increase in the number of cases of retracted operculum in 2019 with a higher incidence in salmon raised at high temperatures, low water quality and high densities.

The trial compared the evolution and efficacy of the Protec functional diet versus a standard diet for two months during the opercular retraction recovery under controlled conditions in 5 gram-Atlantic salmon fry. The diet contained high levels of vitamin C and organic minerals such as zinc and essential oils that protect the skin. Trials were performed at Skretting ARC Pargua.

“We have been able to verify, together with our clients, a rapid reversal of the condition even in stocks with a prevalence of more than 90% with different degrees of severity,” Booth said. In cases of a high prevalence of retraction of the operculum, the company recommends utilizing these feed range for at least four weeks.

Read the study here.