Fish health and fish welfare
Challenges
Farming fish entails responsibility for ensuring that the fish have the best possible conditions. The challenge is to provide for the best possible way to protect and ensure fish health and welfare. The most significant difficulties in recent years have been Sea lice, bacterial wounds, injuries from treatment, CMS, loss of circulation and gill disease.
Our ambitions in this area
We want the fish in our cages to thrive, and aim to protect them as much as possible against unnecessary impact and stress. We care about our fish, and willingly accept the ethical responsibilities inherent in farming fish. Our ambitions are also to make use of procedures to standardise the processes to which the fish are subjected, and to update these as soon as we gain and implement new knowledge. As such, the entire organisation has rapid and efficient access to new knowledge.
How we work in the area
We work with fish health and fish welfare in a number of areas throughout the farming value chain. Lerøy works on the following initiatives in this area:
Lerøy works continuously with welfare indicators by adapting all parts of production in order to ensure optimal fish welfare. As part of our ongoing improvement measures, we make use of several international standards relating to fish welfare and biosafety.
The welfare indicators registered daily are temperature, oxygen, growth, density and category for cause of death. The welfare indicators we measure at regular intervals are lice, gases, salinity, visibility, current, vaccine side-effects, outer blemishes, cataracts, gill status, algae, jellyfish, agents and sedimentation under the facility.
The different welfare indicators have provided us with the opportunity to objectively measure and compare what the different parameters indicate about overall fish welfare. This allows us to make interventions in production in order to prevent factors that impair fish welfare.
All facilities are monitored every month with control/visits by authorised fish health personnel. The purpose of these controls is to identify any room for improvement. Extraordinary controls are also performed, with follow-up and sampling when mortality is higher than normal at the facilities.
Efforts are always made to minimise the amount of time the fish are out of the water for vaccination and sorting. Vaccination procedures include strict limits on how long the fish are on the vaccination table, based on air temperature. The injection point and amount injected are controlled regularly during vaccination to ensure that the vaccination is correctly administered. This is important with a view to reducing the risk of negative consequences for the fish later in life caused by side effects from the vaccine.
We calculate a fish welfare score before and after treatment for all non-medicinal delousing. This provides us with documentation of the scope of the impact, and whether we have to take action to reduce the negative consequences.
The fish are monitored throughout every part of the slaughter process by personnel who have received the obligatory training in fish welfare. All fish are anaesthetised before slaughter, either by electric shock or a blow to the head. The system and method for slaughter require the approval and follow-up of the Norwegian Food Safety Authority. Every day before starting slaughter procedures, the fish are checked and logged to verify a sufficient level of anaesthetisation.
How we measure our impact
On a daily basis, all facilities electronically register the number of dead fish and the cause of death.
Targets per KPI and Results per KPI
Target 2020: Survival in sea, last 12 months according to GSI: 94.5%
Result: 92.2%
This is mainly due to challenges involving wounds and treatment injuries in connection with sea lice.
Results, past 3 years:
|
2020 |
2019 |
2018 |
Survival in sea (%) |
92,2 |
93,4 |
93,9 |
Survival on land (%) |
93,5 |
91,5 |
92,8 |
TARGET 2021: Survival in sea, last 12 months according to GSI: 94.5%
Number of outbreaks of disease
The list specifies dead fish by number and by biomass for the six major categories of mortality.
2018
Cause |
Number of dead fish |
Dead fish, in tonnes |
Wounds |
2,971,578 |
4,536 |
CMS |
799,786 |
3,419 |
Unspecified |
1,187,293 |
3,263 |
Maturity |
339,719 |
1,284 |
Treatments |
1,379,533 |
3,620 |
PD |
323,214 |
949 |
2019
Cause |
Number of dead fish |
Dead fish, in tonnes |
Treatments |
1,469,380 |
3,790 |
CMS |
1,200,800 |
4,848 |
PD |
244,454 |
686 |
HSMB |
225,454 |
621 |
Bacterial wounds |
367,196 |
788 |
Maturity |
158,122 |
615 |
2020
Cause |
Number of dead fish |
Dead fish, in tonnes |
Bacterial wounds |
1,300,982 |
1,990 |
Treatment |
1,182,357 |
3,373 |
CMS |
1,142,944 |
4,543 |
Mechanical injuries |
719,586 |
1,818 |
Loss of circulation |
646,599 |
1,678 |
Gill disease |
601,334 |
1,440 |
What action has been taken
We make use of procedures as governance tools for production. These procedures help us standardise the processes to which the fish are subjected, and they are updated as soon as we obtain new knowledge that has to be taken into account. As such, the entire organisation has rapid and efficient access to new knowledge.
Juvenile fish
Pumps, pipes, sorting equipment, vaccination equipment and hoses are checked at regular intervals, and any faults or defects are rectified before the equipment is used.
For major operations such as vaccination and sorting, the fish are inspected for any damage at regular intervals in order to detect faults in the equipment.
All components used for release of fish are inspected regularly. If we detect an increase in mechanical damage, we stop deliveries until we have discovered and, if necessary, rectified the cause of the damage.
Ongrowing
When releasing smolt into the sea cages, dead fish are inspected for mechanical damage that may have occurred during transport. If we uncover an increased volume of mechanical damage to fish, the delivery process will be subjected to review.
If the different forms of handling fish involve crowding, we follow a procedure describing how to carry out such activities.
We calculate a fish welfare score before and after treatment for all non-medicinal delousing. This provides us with documentation of the scope of the impact, and whether we have to take action to reduce the negative consequences.
In 2020, a number of projects have been implemented to improve fish health and fish welfare. These include:
Laksvel – Norwegian Seafood Research Fund (FHF) project: Development and evaluation of new method for routine welfare monitoring for salmon in Norwegian fish farms: https://www.fhf.no/prosjekter/prosjektbasen/901554/
Gill project: The purpose of the project is to study gill agents in comparison with other production data. The purpose is also to study gill agents during one production cycle of fish at sea, and how status develops.
CMS project: In an attempt to reduce losses caused by CMS outbreaks, studies were conducted to find out whether an increased volume of EPA and DHA in salmon feed would improve CMS status for fish at two different localities. The hypothesis was that an increased amount of EPA and DHA in salmon feed may moderate the negative developments caused by CMS.
Wound project: The project's goal has been to identify risk factors relating to wound development on large fish and newly released fish, and to prepare a list of proposals for measures to reduce risk related to wound development.