HAVBRUKS-Havbruk - en næring i vekst

For salmon, cod and halibut, the fish are often live chilled prior to exsanguination with or without a stunning. From 2007 a new slaughter directive will act demanding that fish are stunned and killed unconsciously. Furthermore the welfare under CO2 suppl ement and chilling is questioned involving possible restrictions or ban. Although electrical and percussive stunning is thoroughly examined, little is known if permanent insensibility is reached in combination with exsanguination. Considering that fish ar e ectotherm, adapted to low temperatures and often prechilled, death is likely a function of the temperature. Hypothermia and the subsequent effect on stress and metabolism has not been studied in fish and there exists a gap in knowledge in how hypercapni a affects the welfare and how it can be used to improve it. Good welfare practice is often associated with good quality. However, chilling and aerobe muscle activity can lead to an early onset of rigor but drip loss, color, gaping and soft texture are ass ociated to other factors such as rigor tension strength, pH, protolytic activity and temperature. The project group aims on answering these questions and improve existing methods Use of EEG, ECG will answer task 1. Use of tunnel resiprometers on cannulate d fish and online blood analyses will reveal how the fish physiologically respond to hypothermal conditions during normoxic, hypoxic and hypercapnic conditions. Metabolism and respiratory drive as a function of temperature will also be calculated. The pro ject will seek new technology using magnetic fields for measuring muscular and neural activity in fish. The project will also identify relations between product quality and welfare, separating events as rigor mortis, drip loss, shelf life, colour and soft texture, so-called Total Product Quality. Summarizing the results by models will provide welfare guidelines for industrial, legislative and scientific communities. The project will educate 4 MSc & 1 PhD candidate.