Availability of fish oil is the single factor in the short term that will limit further growth in salmon production, if the level of omega -3 fatty acids should be maintained at the current level at which EPA + DHA makes up 7.5 % of the fat in the diet . However, the actual nutritional needs for omega -3 fatty acids in A. salmon are not known. The official tables (NRC 2011) indicates 0.5-1.0 % of the feed, corresponding to 1.5 to 3.0 % of the fat in the diet. The report “Fatty fish health” (2013) conclude that;
“it is not shown clearly whether fat accumulation in the intestinal cells affects inflammation in the bowel which may affect their health and welfare. It is also conceivable that lipid accumulation is not chronic, but diminishes after a meal and thus does not have adverse health effects on fish. Knowledge should be provided showing whether fat accumulation in the intestinal cells induced by altered fatty acid composition in the diet has negative consequences for the health, and the minimum level of EPA and DHA is optimal for good intestinal health.”
This project is an extension to the current full-scale CAC experiment where A. salmon fed with two different levels of EPA + DHA (low and standard) is extended with the analysis of gut health – structure and fat accumulation in the intestine in relation to chronic inflammation of the intestinal tissue.
The aim for this investigation is to a) understand the connection between altered dietary fatty acid composition and potential intestinal lipid accumulation; b) to see if there is a link between lipid accumulation and structure and inflammation in the intestine, and c) to communicate our findings to the whole industry.