8:34 am, August 18, Thursday

Phase I results: 2007

I) General considerations concerning animal welfare

Animal welfare was the subject of many discussions since the beginning of their use as livestock species  or as pets.  In nowadays human society, animal welfare is not only a goal, but becoming more and more acute, a necessity. The importance of animal welfare issue is demonstrated by the fact that it is within the interests of governmental or nongovernmental organizations in political, economic, social, technical and professional fields: The United Nations Organization, the Food and Agriculture Organization, World Trade Organization, Council of Europe, European Union, OIE – World Organisation for Animal Health, the Codex Alimentarius, the World Veterinary Association, World Society for Animals Protection, Eurogroup for Animal Welfare.

Until recently, fish – both in fish farms and captured in their natural habitats – have been the subject of these discussions, considering that not feel pain. As such, the notion of welfare apply only to mammals and birds in the farm or in natural environment. But scientific research has disproved the hypothesis of the absence of subjective states in fish (pain, suffering or satisfaction), so the notion of welfare has been extended to these poikilothermic species.

Animal welfare refers ultimately to the quality of animal life. The concept of animal welfare has two sides, an objective side and an ethical, moral one (Tannenbaum, 1991; Sandoe and Simonsen, 1992, Fraser 1999, Report to the Norwegian Parliament no. 12 2002/2003 on the farm animals rearing).

Ethical (subjective) side concerns the intrinsic value of animals, how is it perceived in terms of axiology, there been recorded many differences depending on the practices and areas of human activity (e.g. the meaning of the animal welfare concept is different for animal breeders and public opinion,  more and more interested in assuring a good welfare; also is different between conventional and organic agriculture).

Scientific (objective) side includes all scientific knowledge related to complex influence of environmental factors upon the animal, the way he perceives his condition and how the various physiological and social factors are influencing the general state of the individual.

The two sides of the concept of animal welfare: the scientific side (objective) and the ethical side (subjective) are inextricably linked, the interactions being numerous and complex.

The most widely accepted definition of animal welfare is issued by Broom. According to this researcher, “animal welfare is their status in relation to attempts to cope with the environment.”

In the 2005 Report to the Norwegian Council for Scientific Research, Broom’s definition is extended to the animal mind: “Animal welfare is its subjective experience regarding the mental and physical condition in relation with the attempts to cope with the environment. “

Applying the definition above on the welfare of fish in farms, during transport and before slaughter faces two major difficulties.

First, there is a gap in terms of emotional expression in fishes. It is not known the extent of emotions (positive or negative mental states) in fish, which factors influence it and how they are expressed by fish. As a result, for a fish good welfare, is necessary not only ensure good health and a perfect body functioning, but also avoid any environmental or management factors that could cause pain or suffering. Furthermore, it is a necessity to enlarge the framework of exploratory research in the field of emotional and cognitive functions of these species.

Second, the fish are used in aquaculture in large groups, this making very difficult to observe different welfare indicators at individual level.

Fish shows physiological stress reactions similar to mammals (Wendelar Bonga 1997, Iwama et. Al, 1997) and may be exposed during their economic life to both acute and chronic stress.

Primary stress reaction involving the release of stress hormones (adrenaline, cortisol), which leads to the secondary reaction:, with stimulation of cellular oxygenation and oxygen transfer, mobilization of the energy substrate and reallocation of metabolic energy in detriment to reproductive function and body growth. Mobilizing the metabolic energy gives the body the possibility to cope with the stressor, essential facts of the individual survival.

Generally, stress response has an adaptive role, but repeated or prolonged exposure may cause an maladaptative response (tertiary response). In this case the coping capacity is overwhelmed and different disorders may appear: behavioral changes, reduced food consumption, decreased body weight,  immunosuppression and reproductive indices decreasing. When fish are subjected to severe rearing conditions a long time there are negative consequences for health and welfare or even mortality could appear.

Perception of pain and suffering in fish has raised many controversies over the years, how this issue has been perceived having a major influence on the general attitude towards these animals (rearing, handling or slaughter conditions). To resolve this controversy, two aspects must be studied: pain (nociception) and pain perception.

Nervous system of fish is similar to the mammals, being involved in the transmission of pain sensation (nociception) from different body regions to the brain.  Recent British research (Kirby, 2003) showed that from the 58 of fish cutaneous receptors in the cephalic area, 22 are definitely nociceptors, being stimulated by changes in pressure and temperature rising above 40 Celsius degrees. There are scientists who do not admit the existence of pain perception in fish, birds and even some mammals, arguing that these species are lacking neocortex – the structure responsible for pain perception in most mammals (Rose, 2002). In response, other researchers demonstrated that other brain structures can be used in pain sensation perceiving (Braithwaite and Huntingford, 2004), moreover fish have numerous pain receptors (nociceptors) and their exposure to stress results in major behavioral changes (Sneddon et al., 2003).

The issue of suffering existence in fish as a subjective state is more complex than the controversy regarding the pain perception. Chandroo’s research (2004) focused on the problem of animal awareness to suffering, up to if fish have cognitive abilities similar to mammals. There have been conducted many learning experiments, Chandroo arguing that some of them indicate major learning skills in these animals, which demonstrates the existence of conscious like higher mammals.


In modern aquaculture, fish welfare means ensuring the proper rearing conditions in which these animals can maintain homeostasis, have normal somatic development and can be protected from environmental factors or physical stress. Like many other aquatic animals, fish suffer profound physiological and morphological changes throughout life, from egg stage to adult individual. Therefore, developing methods and methodologies for evaluating the welfare of fish is extremely difficult, involving the study of a large number of factors in a diacronical manner, from egg stage to the fry, fingerling, juvenile and adult and up to the complex relationships between environmental factors and the biological ones. Among the many factors that influence fish welfare, a great importance show the following: physical and chemical environmental factors, dietary factors, social interactions, the existence of different fish pathogens, parasites and predators, but also the procedures for handling, transport and cutting.

Aquaculture is the branch of animal husbandry which has registered in the last three decades the most spectacular growth rate of all industries, worldwide. Forecasts shows that this trend will be maintained in the future. Aquaculture expansion was based on intensive type fisheries, which have generated the same problems in terms of welfare as in other animal species. The main welfare problems in fish include: environmental parameters, feeding, genetic characteristics, density, handling, grading, marking, transport, slaughter and disease.

a) Environmental parameters

Species of fish attracted in the intensive rearing circuit have different needs in terms of optimal environmental parameters: density, temperature, pH, oxygen content, dissolved substances, organic matter load in water, etc.. Water quality is essential for fish health and welfare, thus always must be maintained. Unfortunately, not all needs of farm fish species (regarding environment characteristics) are well known, which could resulting in welfare problems. Low and uneven water freshening attracts flocks heterogeneous development and increase susceptibility to disease. Artificial light is used both in hatchery and in some rearing systems for improving economic indicators (growth gain, feed conversion index). Sudden changes of light level generates panic, death, injury, stress.

b) Food

In fish farms, food is very important and should ensure nutritional needs, to avoid malnutrition. The great development of fish rearing recorded in the last period can be explained by the complete formulation of fish rations and the production of combined fodder for these species (Lymbery, 1992).

Starvation and / or ration reduction are used to adjust production to market demand. By the mentioned practices, the fish can be kept alive with a various growth gain as needed. There were been conducted some researches, especially in salmon, aiming the influence of starvation and / food ration reduction on meat quality at slaughter and specific food consumption, but without addressing the problem of their welfare by measuring and recording changes in behavioral or the stress reactions. Fish can tolerate starvation a considerable time, depending on species and water temperature. High water temperatures can determine strike eyes phenomena, tail biting or cannibalism. In terms of good welfare, starvation should be as short duration as possible.

c) Genetics

Improvement in terms of number of breeding genetically targeted the increase of weight gain, feed conversion index, fecundity, can induce sex monosex and polyploid strains, but genetic resistance to disease.

The problem must be treated as transgenic fish and other animal species carefully, without generating pain. So far not established whether transgenic techniques result in suffering to fish.

c) Density

Increased density is a method of optimizing fish production, but over certain limits may cause: stress, aggressive behavior, water quality reducing,  weight gain and feed conversion index decreasing, physical injury of fins and skin due to the contact between fish and fixed pools or floating cages walls, nets, fish ponds – which represent sites of colonization for different pathogens, disease, restricting swimming, so a poor welfare.

Optimum density of fish should be determined by species and age categories, considering the density for which their welfare is not affected. Thus, the optimal density for salmon, for which in farms are applied densities of 15-20 kg / m3 water (FAWC, 1996), would be 10 kg/m3 water (CIWF, 2002) and for trout, for which in farms are applied 30-40 kg/m3 density (FAWC, 1996), would be 20 kg/m3 (CIWF, 2002).

d) Handling, classification and marking

Like other animals attracted in livestock circuit, fish weight gains are variables, because of heir somatic differentiation, so there might appear small individual agression by the large ones and / or cannibalism. Avoiding aggression and cannibalism may be made by periodic allotments, which involve catching the  fish with the nets or using fish and fry selector.

Allotments, regardless of method used to achieve it, cause distress or harm the skin, result in loss of scales, affecting the welfare of fish (Barton, 1980, Sharpe 1998). Removing fish from the water for three minutes causes a 50 times increasing of cortisol plasma in the period of 30 minutes (Arends et al., 1999). It will  need to be take all necessary measures to prevent abrasion, pull scales or removal of mucus coating, which serves as a physical and chemical barrier for infection, also having an important role in osmoregulation and locomotion. It will be used methods or devices that allow to move simultaneously the fish with a certain volume of water, a transfer method much less stressful and less liable to create injury (FAWC, 1996).

Regarding the identification of fish, in time, more for experimental purposes, there have been used various methods such as: cutting fins in various ways, internal or external application of tags and thermal marking. Except the identification with internal tags, other methods can more or less affect fish welfare.

e) Transport

Live fish transport mode is different depending on size and number of individuals. Transportation can be done with cars, boats, helicopters, aircraft – in various recipients, containers or plastic bags with oxygen excess.

Aquatic Animal Health Organisation – AAH – developed in 2006 two guides on fish transport: a guide to fish transport by land and another for transport by water.

Whatever type of recipient or container used, they must be designed to not harm the fish during the trip (to have smooth finish and to be rounded,  with no sharp parts). Supervision during transport, inadequate water quality hygiene may lead to stress, injury or even death for a smaller or a larger proportion.

Reducing stress during transport for breeding fish can be ensured by the use of anesthesia and a recovery period.

Main determinants of the fish welfare during transport are: quality of the fish, the oxygen, ammonia and carbon dioxide in the water, pH, temperature and density.

f) Diseases

Often there is a strong correlation between growth and operating practices and the incidence of fish diseases. In field can be recorded situations in which fish, because growth and rearing conditions, can contract a number of diseases that affect their welfare.

Among the diagnosed diseases are: skeletal malformations, eye and muscle disorders, consequences of inadequate growth and rearing conditions. Mentioned diseases are of concern both for the fish welfare and for farmers, because it generates economic losses for consumers – by affecting the product quality and food safety.

Skeletal disorders causing in juvenile salmon open mouth syndrome due to the fact that they can not close the mouth and can not feed normally. Open mouths syndrome generates high mortality after yolk sack absorption. The cause is a too high water temperature during the incubation period.

Soft tissue abnormalities in Atlantic salmon refers to the absence of transverse septum, the changes in cardiac morphology or topographic changes (situs inversus). These modifications are responsible for heart failure, reduced tolerance to stress and high mortality. Fish with such diseases have reduced performance. The causes are deficiencies in the selection of breeding, an intensive feeding and a restricting swimming for these.

Cataracts in salmon causes blindness and is a significant problem, recording a high frequency. Blind salmon is agitated, shows injuries and has a low weight gain.

Bacterial diseases in fish were mainly controlled by intensive use of antibiotics. Currently, control of bacterial diseases is done by using of adjuvanted vaccines. Local reactions after vaccination are of interest in terms of welfare. Severity of the reactions after vaccination is lower in specimens larger than 70 grams and in water with temperatures below 10°C. Sporadic adverse reactions, manifested by adhesions, some weight gain reductions and spinal deformities, are not an obstacle in extending immunoprophilaxy .

g) Cutting (Slaugter)

Fish are subjected to handling stress at loading, during the journey, at arrival and during the storage until slaughter. Rough handling can lead, besides injuries, to the death of fish.

Time fish are held without water before cutting, regardless of method used, must not exceed 15 seconds.

Establishing universal slaughter procedures is difficult because of the significant differences between species. Thus, while carp and eel are resistant to hypoxia, salmonids are sensitive. Consequently, the level of oxygen in storage areas must be optimal for each species.

Cutting methods are different, some of them come in total contradiction with the principles of animal welfare.

To avoid unnecessary stress and pain before bleeding is required that fish be brought into a state of loss of consciousness (stunning), which must last the entire duration of bleeding. Method for inducing unconsciousness should not cause stress or pain.

Cutting fish by human methods (to ensure their welfare is satisfactory) must be preceded by setting of programs for slaughter by the competent authorities (Report concerning human cutting / slaughter of fish, developed by the Aquatic Animal Health – AAH, 2006, institution within the OIE – Office International des Epizooties).

Methods of stunning fish are two categories: mechanical and physical / chemical.

Mechanical methods include: stunning by percussion, penetration and Iki-jime, stunning by shot.

Physical methods / chemicals include: electrical stunning, adding chemicals to water (benzocaine, iso-eugenole, metacaine, metomidate, rotenol).

Besides fish stunning and euthanasia methods previously submitted and considered acceptable in terms of ensuring their welfare, there are totally unacceptable methods, causing their suffering: the use of CO2 alone or in combination with cooling water; ammonium or salt baths used in eels; asphyxiating fish – particularly inhumane, given that fish sensitivity does not disappear during slow induction of this method, bleeding – in case is applied to fish that have not previously been stunned.

There are other methods of killing fish, of which mention decapitation (causing death by cerebral ischaemia secondary of head detachment , acceptable only when is preceded by anesthesia) and maceration (used for the destruction of embryos and larvae egg – juvenile).

III) Methodology for fish welfare assessment

As for other animals of economic interest, in fish welfare assessment can be done by one of the following methods: based on behavioral indicators, based on management system and practices, based on numerical integrative systems and on the HACCP.

In terms of behavioral indicators, they are more difficult to apply to fish, these didn’t have voice responses, facial or postural. Increased incidence of agonistic behavior in fish (proactive) is a sign of poor welfare. Aggressive behavior at individual level is measured using the dominance index (number of aggressive manifestations of individuals / number of aggressive events in group x 100) or the average consumption level of food (individual average consumption of feed pellets / consumption of pellets in group x 100). For the interpretation of fish welfare may be used following behavioral indicators: swimming hieratic (ataxia) or swimming at the surface, mouth and opercula open, fish grouping near the water aeration devices (secondary to gill disease or poor water oxygen content), loss of appetite, swimming in circles or increased incidence of jumps outside the water (which reveals parasitoses or low water quality), color changes. Thus,  general hypermelanosis in fish regardless of species, shows that they are subjected to chronic stress, while a lighter color (pale) usually reveals discomfort due virosis or bacteriosis.

To assess fish ethograme, with particular reference to their mobility in tanks or transport containers may be used non-invasive last generation methods, like video recording or even telemetry (Smart Tags to measure respiratory frequency of fish in ponds: www.seafoodplus.org, www.thelma.no). In addition, behavioral indicators prove their usefulness when is assessed the influence of different internal/external environmental factors upon welfare, by preference or aversion studies.

Fisheries management systems are welfare indicators easy to define and measure, including: method of feeding, ration composition, existing programs of control of nutritional and metabolic diseases, stocking density in tanks or transport containers,  existence, relevance and timeliness of control programs for infectious and parasitic diseases (infectious necrotic pancreatitis, viral hemorrhagic septicemia, furunculosis, infectious dropsy, branchiomicosis, saprolegniasis, coccidiosis, ligulosis, argulosis etc..) for fish farms. Factors related to management practices (eg, professional and practical skills of stockmen) are harder to measure, virtually impossible in a single visit to the farm.

Welfare assessment based on numerical integrative systems is the most common method of welfare assessment in farm mammals and birds species. Their integrative nature derives from the fact that join factors related to housing conditions or management systems and practices (engineering-based parameters) with behavioral and pathological factors (animal-based parameters). Because of the essential differences of fish in comparison to higher vertebrates, respectively physiological differences (body temperature and its dynamics, since they are poikilothermic species), environmental (vulnerability to poor water quality and its pollution) and ethological (behavioral patterns completely different from mammals), factors or area of influence within assessment sheets from welfare evaluation systems used in mammals or birds can not be extrapolated to fish.

Within the project COST 867 have been taken the first steps in this direction (Burchmannn K., 2006). Objective welfare indicators (Object welfare indicators – OWI) are classified in two broad categories: direct (which refers to the fish) and indirect (referring to the rearing conditions provided: water quality management, etc.).. Regardless of type, they can be defined as operational when can be immediatly corrected, leading to rapid improvement of the  fish status , and strategic, requiring a long period for the occurrence of improvement.

A working group of the named project has developed a welfare assessment that grouping these indicators in four tables. In the first table are gathered direct indicators (fish size, body development factor, condition and color of skin, opercula and fins, hipaxial and epaxial muscle, color of the organs and the presence of various malformations, appetite and the behavioral pattern of air piping near the water surface) and indirect indicators (density, mortality  in fishfarm,  actual unit size). In the second table are gathered water quality parameters (temperature, salinity, pH, flow velocity, biological oxygen consumption, total ammonia nitrogen, nitrate, nitrite, turbidity, phosphates). Table 3 refers to the fish diet (composition and hygiene of food rations), and Table 4 to specific virosis, parasitoses and bacteriosis.

Welfare assessment based on the HACCP system was proposed by Grandin (1998) and adopted widely in the United States. Currently Europe states (Netherlands, Germany) make great efforts to introduce welfare assessment systems based on HACCP principles. For fish, in a HACCP system for welfare assessment can be included: the general condition of the individual in terms of mucocutaneous mucous surface, the ammonia content of water, oxygen dissolved in water, salinity; storage density. In salmonids from both farms or caught by angling can be used as an indicator of welfare for the body condition factor (K), which reflects fish feeding conditions. The factor shows large variations, under the influence numerous physiological factors, which fluctuate throughout the stages of development (fry, youth, adult breeders). Similar parameters, referring to the length / weight and fish were proposed by Anderson and Neumann (1996) to monitor the condition at a population level in fish pools or natural water. Body condition factor is calculated as (10N x W) / L3 (where W is fish weight in grams, L is fish length in mm from cephalic extremity to posterior fin limit, N is a coefficient determined by repeated trials on a large number of fish and has a value of 5). Depending on this factor, the condition of fish could be described as: excellent – k over 1.6, good – more than 1.4, acceptable – k over 1.2, Poor – k over 1, very poor – k is between 1 and 0.8.

Difficulty of applying HACCP strategies for assessing welfare in fishfarms and continue to optimize it in time lies in the fact that each critical point effect upon welfare can not be determined accurately. Various factors – such as stocking density – exerts its effect by others – such as water quality and fish behavior (Ellis and others, 2002, Turnbull and others, 2005, quoted in the Welfare of Fish in European Aquaculture from 162 Meeting of the CSO: 14 to 15 June 2005).

Evaluation of animal welfare during transport are made based on: behavioral indicators, physiological indicators, biochemical indicators, mortality during transportation, injuries and lesions of carcasses (The Welfare of Animals During Transport-Details for horses, pigs, sheep and Cattle, Report of the Scientific Committee on Animal Health and Animal Welfare, March 11, 2002).

From the behavioral indicators, in order to determine fish welfare during transport are likely to use: the level of intraspecific aggression and the intensity of reactions of avoiding stressful situations.

In terms of physiological indicators, it was given the possibility to determine the welfare of fish based on cardiovascular activity, the respiratory frequency (LE Barreto, GL Volpato, 2004), haematological parameters which reveal osmotic pressure and isohidrya mantaining: osmotic pressure, blood pH (analysis proposed in the COST meeting in La Rochelle 1999). Of these, more affordable are the analysis of respiratory and heart rate, non-invasive methods, so desirable in terms of ensuring good fish welfare. Increased heart/respiratory rate reveals stress, which leads to poor welfare of fish.

The most commonly used in determining the welfare of animals during transport, biochemical indicators meet a wide range of laboratory tests, of which, until now, for monitoring the level of stress in fish (so as poor welfare indicator) are used: ACTH’s determination, plasma cortisol and cholesterol (Dutta T, Acharya S, Das MK, 2005, Veiseth E., Fjaera SO, Bjerkeng B, PO Skjervold, 2006).

Assessment of animal welfare before cutting / slaughter is usually achieved by HACCP, monitoring these critical control points: the effectiveness of stunning animals, the proportion of conscious animals after stunning, vocal manifestations of animals, animals slipping and falling, the percentage of animals on which is applied electrical pulse (with electric prod). Given the fish, could be keep as applicable only the first two critical control points, then could be added more.

To monitor the potential critical control points of fish welfare, respectively stunning efficiency and percentage of fish aware after stunning, will take into consideration that a proper stunned fish is characterized by: cessation of respiration (opercular moves), loss of visual evoked reflex (electrical response of the  brain occurred after visual stimulation, measured with electrodes placed in the cephalic extremity), immediate loss of vestibulo-ocular reflex (rotary nystagmus); lack of caudal reflex and other signs of muscle activity (AAHMar 2006 Report).

IV) Fish Protection Legislation in fish farms, during transportation and in slaughter units

Compared with terrestrial farm animals, fish welfare issue and the creation of its legal basis concerned not so much consumers of animal products, manufacturers or initiators of law. The situation is caused by three reasons:

– In general, these animals are perceived by public opinion as being not endowed with feelings and not able to generate compassion like homeothermic animals, closer to the human in phylogenetic scale;

– Has not been yet reached a consensus in the scientific world on the issue of perception of pain or suffering in fish;

– Large scale, industrial aquaculture developed relatively recently (Wolffrom and Dos Santos, 2004).

However, in recent years have been noticed an increasing of interest for fish welfare in general and especially in aquaculture, in the context of numerous scientific studies suggesting that the subjective state of pain and suffering exists in fish, and reports describing improper rearing and growing conditions, often to the detriment of health and welfare status.

The first document raising the fish welfare issue is Protocol 33 of the Amsterdam Treaty (1997). Subsequently, the OIE and the EFSA (European Food Safety Agency) form their working groups on issues of fish welfare.

Currently, these European laws regulating aquaculture and the protection of fish in farms, during transport and before cutting:

– Communication of the European Council Commission and European Parliament entitled Strategy for Sustainable Development of European Aquaculture (Brussels 09.19.2002)

– Recommendations concerning farmed fish, document drafted by the European Convention on protection of farm animals (December 5, 2005) and which entered into application on June 5, 2006;

– Joint statement of the OIE and European Union Council of Europe entitled Animal Welfare in Europe: achievements and perspectives, adopted in June 2006 (present declaration supports cooperation in all activities related to animal welfare – from acts proposal, to train veterinarians and everyone involved);

– Convention on the protection of animals during international transport, adopted by the Council of Europe on June 11, 2003 and came into effect on March 14, 2006;

– Directive 78/659/EEC for the protection of water courses to maintain fish populations.

On the american continent, most interest in this area was showed by Canada. Interest is reflected in a law for the protection of fish (1997) and numerous guides (transport, fish use for research and other scientific purposes, etc.)..

The most common organisms were actively involved in the protection and welfare of fish are: Council of Europe, the European Food Safety Authority (EFSA) – in which AHAW Working Group, which published two documents related to the welfare of fish: one with reference to their transport and stunning / euthanasia methods, OIE (which sets out various aspects of fish health and welfare in its annual publication – Aquatic Code),  FAWC (who produced a report on the welfare of fish in farms since 1996) , European Commission of Health and Consumer Protection and the one for the maritime affairs and fisheries.

At European level, were developed or is developing several research projects related to fish welfare: FASTFISH, WELLFISH, WEALTH, AQUAFIRST, FINEFISH.

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