Nofima has for many years conducted studies of the farmed fish's ability to cope with the aim of finding simple, practical and profitable solutions to complex problems. Fish farming is not based on best duplicating natural conditions, but we are searching for optimisation of everything from the fish's necessities to practical operational routines.
Development of welfare indicators
We have today developed a series of methods to measure the fish's ability to cope the farming environment. Some of the methods are based on individual fish, such as a swimming tunnel, while others are carried out in smaller groups or in tanks and cages with normal commercial densities.
Many of the behaviour methods in our behaviour laboratory are based on individual fish, where we for example observe aggression in groups or trace movements using advanced video technology. Physiological analyses are often based on blood tests, e.g. to measure stress. In addition, we use advanced fish tags, including a SmartTag developed in the EU project SEAFOODplus, which measures the respiration pattern of free-swimming fish as an indicator of the fish's welfare.
The fish's behaviour and physiology are connected
Many of the welfare programmes and experiments at Nofima integrate behaviour and physiology. In order to understand what an animal is doing, we have to be able to measure the physiological effects of the behaviour. Further, in order to be able to reduce the amount of unwanted behaviour, we have to be able to alter the farming conditions for the fish.
Fish density is a good example: a low density can lead to an increased level of aggression between the fish, which in turn leads to a hierarchy in which the most dominant fish get access to the feed they want while the losers experience physiological stress reactions, little food and poor growth. A high density is not necessarily a welfare problem for the fish in itself as long as the water quality is satisfactory.
Fish health is how they are - fish welfare is how they cope
The fish's welfare influences the fish's health. However, there are many complex connections between health and welfare. We study directly how different farming conditions influence susceptibility to disease with standard disease challenge tests, and indirectly how different conditions influence the fish's immune system.
We also study how farmed fish perceive pain, and we have developed collaborations with research communities in human medicine to look more closely at how the brain interprets different stimulations of the senses, e.g. sounds or potential pain.
Fish welfare influences the fish farmer's economy
Measures to improve the fish's welfare have a financial influence on the fish farmer, but not necessarily in a negative direction. We work on the basis that the best measures to improve the fish's welfare are also those which have positive economic effects from both a business and community perspective.
We are collaborating with bio-economists to develop economic models which illustrate which measures are "profitable". Investing in equipment to advance the fish's welfare can be expensive. However, this can be worthwhile in terms of
- Better feed utilisation
- Increased growth
- A lower rate of mortality
- Consumers willing to pay a higher price for a more ethical product
- A better reputation for the aquaculture industry
Fish welfare from fish farm to plate
Fish welfare is a relevant issue along the entire supply chain, and some projects aim to study individually marked fish the whole way from the juvenile stage via slaughter right through to ending up on the consumer's plate. We are interested in the biological effects of intensive fish farming, how this affects the muscle quality (e.g. shelf life and sensory quality) and how this affects consumer attitudes.
Trials show that there is a connection between what we do with the fish and the quality of the end product. Consumers are becoming increasingly more interested in the so-called ethical quality of products, and information about ethical production can have a positive effect on how consumers perceive or accept farmed fish.
