2013 Annual Report
1a.Objectives (from AD-416):
Develop an in-vitro test to determine the presence of intestinal enteritis in rainbow trout.
1b.Approach (from AD-416):
Rainbow trout fingerlings (average 9 grams per fish initial weight) will be fed diets varying in type and level of soybean meal. After 16 weeks of feeding the experimental diets, blood from 40 fish in each tank will be sampled. Plamsa will be tested for LDH, bilirubin, immunoglobin, fibrinogen, ATPase. Plamsa will also be evaluated using NMR by EWOS Innovation in Norway. Documents Trust iwth EWOSInnovation. Log 43497.
This project relates to the above mentioned parent project because soybean meal, or slightly processed soybeans, contains compounds that cause intestinal problems in many species of fish including trout. If we had a rapid way to determine if this condition existed, we could more rapidly evaluate the quality of our plant based feeds. A cost effective, plant-based trout feed is a main objective of the parent project.
Fish were fed the various diets and tissues and plasma were collected from a representative sample of fish in each tank. Comparing the intestinal histology data to the plasma data, no correlation could be found. With some individual fish the presence of enteritis did relate to changes in plasma, but the variation with treatment was large enough to obscure the effects. This project has been terminated, but we will continue to look for other ways to determine if there is a detrimental effect of diet on intestinal health besides histology.