Physiology of Finfish and Shellfish (2+1)

5.1.4. Categories of stress

Stress may be divided into three categories. They are a) response to cultural procedure b) response to disease c) response to water pollutants.

Stress response to culture procedure

The intensification of fish culture and the consequent rearing of fish in man-made environments has resulted in the fish being exposed to a number of stresses which they do not experience at all in natural environment or do not experience to the same degree.

First group

It is the consequency of the artificial environment itself and can include such factor as temperature, salinity charge, stocking density, O₂ concentration, pH and water velocity etc

The intensification of fish culture and the consequent rearing of fish in man-made environments have resulted in the fish being exposed to a number of stresses which they do not experience at all in natural environment or do not experience to the same degree. First group stimulus being referred to as the stressor. The components of this response are collectively known as the General Adaptation Syndrome (GAS) which can be divided on a temporal basis into stages of alarm. It also been demonstrated by schereck who presence evidence to show that dimination of "awareness" reduces the magnitudes of the physiological stress response.

It is the consequency of the artificial environment itself and can include such factor as temperature, salinity charge, stocking density, O₂ concentration, pH and water velocity etc

Second group

It relates to the stress of the fish that is fed and includes such factors like protein quality vitamin cone., lipid type, mineral level etc .,

Third group

It consist of handling procedure like capture, anaesthesia, grading, storing by sex etc.,