Evaluation of the distribution of adipose tissues in fish using magnetic resonance imaging (MRI)

In aquaculture, the accumulation of excess fat in fish, which is mainly sourced from unbalanced diets or feeding strategy, would impair fish health and has been a serious problem in cultured fishes. Adipose tissues are specific tissues for fat deposit in many fishes, therefore the knowledge of the anatomic distribution and total mass of adipose tissues is the basic premise to study the mechanism of fat accumulation in economic fishes. However, this issue has not been well documented. Our present work investigated the distribution and content of adipose tissues in five economic fishes with different feed habits and farming environments by using the MRI technique. Through this work, we described the shape, distribution and mass of adipose tissues in different economic fishes for the first time. We also developed an ideal MRI scanning method for live fish, which largely expends the application of the MRI technique in nutrient physiological study in aquatic animals. Because the adipose tissue has been widely accepted to be closely related to nutrition status and diets in the most of farmed animals, including economic fishes in aquaculture, our present study has close relevance to aquaculture.