The effect of rearing density and dietary aflatoxin B1 on proximal intestine of rainbow Oncorhynchus mykiss )trout)

In the present study, the effect of various rearing density and dietary aflatoxin contamination on the proximal intestine of rainbow trout was investigated. To this end, 400 fish with an average body weight of 90 g were stocked in eight 300 l tanks containing 200 l water at two densities of 15 and 45 kg.m-3. At each density, diets with or without 50 ppb aflatoxin were fed to fish three times a day at 3% of their respective body weight. At the end of the experiment, proximal intestine of fish was taken and fixed using Bouin s fluid. After tissue processing, paraffin blocks were prepared and thin tissue sections were prepared and stained using H&E method. Results showed that there were no significant changes in the tissues of fish reared at various densities, however, those fish reared at higher density and fed a diet containing 50 ppb aflatoxin B1 showed some alteration and villi did not normal structure. In conclusion, it is conceivable that fish was able to tolerate higher rearing densities, but when dietary contamination such as aflatoxin comes to play, it would not be possible for fish to strive. However, solid conclusion requires complementary studies including assay of digestive enzymes activity and redeox status of the intestine.

کلیدواژه ها:

Rearing density ، Aflatoxin ، Intestinal Histology ، Rainbow Trout (Oncorhynchus mykiss)