Control of medicines 


Excessive use of antibiotics can result in antibiotic resistance in some areas, a major risk factor for health and for fighting diseases, particularly for humans. 

In general, food production from animals require the use of medicines to treat diseases, not least with a view to animal welfare.  If not controlled, the use of antibiotics and other medicines in conventional fish farms could contribute to an undesired and negative affect on humans and the environment.

Our ambitions in this area

Lerøy aims to avoid unnecessary use of antimicrobial agents and other medicines. The use of antimicrobial agents is seen as a last line of defence and only applied in situations where deemed necessary to protect fish welfare, and when factors relating to food safety, the environment, resistance and effect have been clarified. Lerøy emphasises the importance of a preventive operating practice, aiming to reduce the number of incidences of disease, thereby reducing the need to medicate fish.

How we work in the area

All medicines used must be prescribed by authorised fish health personnel. Before starting medication, a risk analysis is carried out to assess measures not involving medicines, and the impact on any vulnerable habitats and species close to the facility.

How we measure our impact

All use of medicines is logged in our own production management system. Details such as the name of the person who prescribed the medicine, approved assistant, active substances, quantity, treatment period and retention period for the fish are all registered each time treatment is administered.

Environmental surveys are conducted at least once a year in the zone surrounding each facility. These surveys are conducted by an independent company. The analyses are in three parts: fauna, chemical and sensory. The analyses result in a score from 1 to 4, where 1 is the best result. If the score is 3 or 4, action must be taken to improve conditions at the facility. Similar and more extensive surveys are conducted outside the immediate surroundings at least every five years.


Targets per KPI and Results per KPI

Target 2021: Annual use of antibiotics in the Group: 0 kg

Result 2021: 0 kg

Result 2020: 18,99 kg One treatment with 18.99 kilo total, which is 0,08mg Florfenikol/kg produced fish.

This was treatment administered to small, newly released fish, for a bacterial infection, Tenacibaculum sp. and Moritella viscosa.

Result 2019: 0 kg

Target 2022: Zero use of antibiotics


Action taken due to results per KPI

Lerøy avoids unnecessary use of antimicrobial agents. To achieve this, a number of different preventive measures are implemented and are part of a preventive operating practice including vaccination, risk management, disease control, structural measures, early diagnoses etc.  A number of preventive projects have been initiated to prevent future use of antibiotics. These include:

  1. Tenacibaculum spp. as the cause of atypical winter wounds on Norwegian farmed salmon – Norwegian Seafood Research Fund (FHF) project: Project period: 01.10.2017-30.09.2021. The aim of the project is to identify risk factors for the outbreak of Tenacibaculosis and to characterise toxin production in Tenacibaculosis spp. The project also aims to test “proof of principle” for the use of toxins as antigens in vaccines.
  1. Limit the effect of tenacibaculosis in Norwegian fish farming (LimiT) – Norwegian Seafood Research Fund (FHF) project: Start/finish: 10.10.2017 – 15.12.2020. The goal with this project has been to gain a better understanding of how a disease or illness progresses, and to identify virulence factors in the bacteria. Trials involving infection have shown that the skin on smolt that have been kept in waters with lower salinity (26 per thousand) than normal sea water prior to release to sea may be better able to combat infection. Comparisons over time in the infection model demonstrate that the skin is in significant development, and that this most likely affects the outcome of the infection. This implies e.g., that the outcome of exposure to skin pathogens will largely be affected by the post-smolt phase of the skin. The results indicate that the industry may be able to reduce the consequences of tenacibaculosis by exposing the smolt to lower salinities during a period prior to release to sea.
  2. Lerøy internal wound projects: Different projects that aims to reduce prevalence of bacterial wound-infections. In 2020, a project was implemented to identify risk factors for wound development on large fish and fish recently released to sea.
  3. Vaccine trials: To contribute to development of new/more effective vaccines.