Forsøksdyr: Pre-slaughter morbidity and mortality of Atlantic salmon

Godkjenningsdato 11.12.2018

Growth-stunted (GS) fish
GS fish in aquaculture represent a highly variable (typically 2-20%) fraction consisting of dropouts which display behavioral inhibition, reduced feeding, stunted growth, and pathological stress responses. These fish represent both an economical loss and a welfare problem. It is necessary to deliver knowledge on robustness traits, which may be implemented in on-going breeding regimes in order to improve fish survival rates and their quality of life. In the current proposed experiment, we will treat GS fish with a 5-HT agonist which will decreased 5-HT signalling and may reverse the expression of the GS phenotype. The results obtained from this experiment will help establish 5-HT as a welfare indicator to help diagnose vulnerable individuals. There expected distress on experimental animals will be minimal. These fish will be taken from seacages, an environment in which they cannot cope, hence their behavioral phenoype and will be moved to a less stressful environment (our experimental tanks). The solution which will be used on experimental fish has been associated with reduction in anxiety behavior, which will in fact increase the welfare of the treated fish.

Reducing production loses and increasing welfare in farmed salmon is an important goal within the
aquaculture industry and the general public. Increasing or knowledge on brain mechanisms associated with susceptibility for disease and mortality in farmed salmon will help reach this goal.
This experiment has been designed to minimize the number of experimental animals while still providing useful scientific results and previous knowledge on this topic has helped us establish the total number of individuals Atlantic salmon used for the experiment to 52 individuals.