CCAC - Programs -> Guidelines -> Appendix B

	Contact Us \| Site Map \| Français

CCAC guidelines on: choosing an appropriate endpoint in experiments using animals for research, teaching and testing

OBSERVING FISH BEHAVIOR

The following points are important in ensuring that observation of the fish occurs without missing important observations, or inadvertently altering normal behavior or biasing results:

Lighting

Many fish species "prefer" low light intensity, dark backgrounds or both in order to "feel" secure (as indicated by a reduction in what could be called anxious or nervous behavior). It is important that the investigator achieve an acceptable compromise between adequate lighting and background color combination which will permit reliable observations by research personnel while causing minimal distress to the test animal. A combination which often works well is shielded lighting located directly over the tank or aquarium combined with no or very low intensity room lighting. This accomplishes two goals: observer eye accommodation to low light; and reduced visibility of the observer to the fish. If the walls or portions of the wall of the tank are transparent, one must keep in mind that if the differential between the light intensity inside the tank (high) and that outside the tank (low) is sufficiently great the transparent areas of the wall act as mirrors and fish with strong territorial behavior will respond as though defending their territory and may not feed normally. The investigator should also keep in mind that the ability to make detailed observations in low light intensity is affected by age of the observer and by certain medications.

Comfort of the Observer(s)

The observation environment should be sufficiently comfortable for the research personnel so that they conduct their responsibilities thoroughly and in an unbiased manner (i.e., it must not be easier to observe one experimental unit than another).

Planes of Viewing the Fish

The unit for housing the fish (e.g., tank or aquarium) must be suitable for the species and for the observations required. If a change in the posture of the fish in the water column is an anticipated clinical sign (particularly a head or tail down attitude), it is important to be able to view the fish from the side, as a much more pronounced change in posture is required before it can be detected by observation from the top of the tank. If clinical signs such as respiration rate and depth of respiratory movements are to be documented, these are often best observed from the vertical plane of the fish (i.e., directly above or below the fish) for observing opercular movements, or the horizontal-lateral or horizontal-frontal plane of the fish for observing mouth and opercular movements.

Observer's Clothing

Individuals making observations should avoid wearing white or light colored clothing (e.g., white lab coats) as many of the fish species used in research are sufficiently "wild" or undomesticated that white remains an alarm signal.

CLINICAL OBSERVATIONS SPECIFIC TO FISH

The five aspects of an animal's condition which should be evaluated in assessing pain, distress and discomfort (Morton & Griffiths, 1985) apply equally to aquatic species, with some qualifications regarding the importance of body weight changes as an indicator of pain and/or distress.

In the more traditional laboratory animals, the concern is usually for abnormal or unanticipated weight loss. In endothermic aquatic animal species, particularly when housed in water at or below their species optimum temperature range, weight loss is extremely slow. A slower than normal rate of gain may be a more sensitive indicator of sub-optimal environment or health.

Certain species of fish undergo normal physiologic anorexia associated with environmental changes or sexual maturation or both. Lack of attention to environmental criteria can precipitate normal physiological anorexia.

Experience suggests that approximately 6-7% of Atlantic salmon in sea water in a tank will not eat. However, when moved to another tank, particularly if they are larger fish in a new situation, they will begin to feed normally.

Change in feeding activity or in feed consumption of the experimental unit (the tank) is a more immediate and sensitive indicator of abnormal environment or health than weight changes.

SOME SUGGESTED OBSERVATIONS FOR QUANTIFYING PAIN AND/OR DISTRESS IN FIN FISH

color change (usually a darkening associated with disease or bilateral blindness)

[ Appendix A ]	[ Table of Contents ]	[ Appendix C ]
	[ Back to top ]