ABSTRACT
We know that fish consume other living matter from their environment; unlike plants they are incapable of synthesizing organic matter (Part I, Chapter 2). The intake of food supplies their energetic requirements (movement, basal metabolism, etc.), reproduction and growth. Fish are no different from other farmed animals except with regard to temperature. They live in water-a medium with a high specific heat (Part I, Chapter 1)—and fish, like the majority of aquatic animals, are poikilotherms. The temperature of the blood is therefore close (around 1°C) to that of the environment in which they are living. There is thus no requirement to consume energy in order to maintain body temperature at a different level to that of the environment. These animals living in water must adapt to all the other parameters (dissolved gases, salinity, light, pH, pollutants, etc.) which have a bearing on their nutrition.
