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AWSI working method

What are the advantages of working closely together with retailers?

The food retail trade determines which products are included in its range. The consumer decision is based on the available range.

However, product quality and existing certificates do not always play the decisive role in the purchase decision. It is often a price matter. If food retailers decide to offer only certified products in a product group, it is easier to implement better standards on the market.

As soon as AWSI’s animal welfare recommendations are reflected in the well established certificates for foods from aquaculture, the retail trade can adapt its product range accordingly. The prerequisite for this is that enough producers follow the recommendations. AWSI’s work aims to accelerate this process.


What does responsible feeding of fish in aquaculture mean?

Responsible feeding of fish means feeding high quality food that is appropriate for the species and age of the fish, in adequate amounts and in a manner that is appropriate for the fish. There are feeds that float on the surface or sink to the bottom, and thus can be adjusted for the particular behavior of the fish. Feeding over a wide area ensures that all fish have access to the food, that there is less competitive behavior and fish population divergence, and that damage to the fish is avoided.

Why can’t fishmeal be completely eliminated from the diets of some aquatic animals?

Using species-appropriate feeds in aquaculture is animal welfare friendly, but may conflict with efforts to provide sustainable feeds. 

While some cultured fish species are suitable for pure vegetarian rearing, other species require essential nutrients contained in fishmeal for their health, growth and welfare. Fish species such as salmon or trout cannot be raised in an animal welfare-friendly manner without these nutrients.

Intensive research is currently being carried out to gradually substitute fish meal and fish oil in feed without causing animal welfare problems. The aim is to find suitable alternatives that are compatible with animal welfare and also ensure appropriate growth. For example, attempts are being made to provide the necessary essential nutrients by additionally feeding certain algae.

Why doesn’t AWSI give recommendations on the amount of feed?

The adequate amount of feed is fish species and age specific. Most feed manufacturers give sound recommendations on the dosage of their feeds.

It is important to note that the water quality must not deteriorate due to excessive feeding. The food must be well absorbed and utilized by the fish. For some fish species, it is also important to pay attention to temperature-dependent feeding. If the water is too cold or too warm, the appetite suffers.


Do fish feel pain?

According to scientific studies, fish have pain receptors and the stimuli are transmitted to the brain. A potential pain stimulus activates areas in the brain of the fish that most likely perform the same task for the fish’s perception as the areas of conscious pain perception in more highly developed vertebrates. In addition, behavioral patterns and decisions of fish – for example, the learned avoidance of situations associated with injury – indicate a conscious perception of pain.

More information (available in German only) can be found here:

Product quality

What effect do AWSI’s animal welfare recommendations have on food quality?

Scientific studies show that the meat of stressed fish has poorer product quality than the meat of fish that have not been exposed to stress factors. Severe or repetitive stress can lead to altered color, tissue fluid leakage and structural changes in the filet, as well as weight loss during freezing and smoking. 

By implementing the animal welfare measures from AWSI’s recommendations, stress can be reduced to the utmost extent. This improves food quality.

Source: Wedekind, H. (2004) Lebensmittelqualität beim Fisch – Konsequenzen für die Hälterung und Aufbewahrung. Seminar »Tierschutz in der Fischerei«, edition 2, series of the Fisheries Association of the state of Baden-Wurttemberg (Landesfischereiverbandes Baden-Württemberg e.V.).

Recommendations in general

Why are AWSI’s recommendations not species-specific if the requirements of different fish species are so different?

As a first step, AWSI has identified the most important areas for the welfare of aquatic life and developed general recommendations. These apply generally to every farm and every species cultivated. Implementing them internationally is in itself a major step forward for animal welfare in aquaculture.

In the upcoming implementation of the general recommendations in training courses suitable for operations, it is necessary to take into account species-specific characteristics. For example, percussive stunning (knocking) is only appropriate for certain fish species in terms of animal welfare, but less so for others. AWSI works with research institutions and technology providers to incorporate new scientific knowledge and technical innovations into its recommendations.

Why doesn’t AWSI make specific recommendations on stocking density?

The stocking density must always take the species and age of the fish being raised into consideration. What seems beneficial for one species can be fatal for another, and young fish often join together to form schools, while older conspecifics tend to claim a territory for themselves.

Excessive stocking densities in an aquaculture environment can lead to crowding, stress and injury, while too low stocking densities can trigger territorial behavior in some species. Both must be avoided. Furthermore, available water supply and exchange, as well as water quality, must be considered when determining stocking densities. The more animals live in a water body – pond, basin – the faster the water quality can deteriorate.

Ultimately, the level of stocking density that does not lead to conditions in a farm that are detrimental to animal welfare also depends on the quality of farm management. A fish farm with optimally trained employees who recognize harmful changes in time and successfully counteract them can work with higher stocking densities without any problems than a poorly managed farm.


Why is fish adaptation so important when changing from transport water to culture water?

Culture and transport water should always have a similarly good water quality. If there are too great differences in water quality between transport and culture water, for example in temperature, oxygen saturation and the content of excretory products, a slow adaptation is necessary to avoid stress reactions of the animals.

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