Influence of certain soybean antinutritional factors supplemented to a casein-based semipurified diet on intestinal and liver morphology in fingerling rainbow trout Oncorhynchus mykiss
Article first published online: 5 OCT 2008
© 2008 Japanese Society of Fisheries Science
Volume 74, Issue 5, pages 1075–1082, October 2008
How to Cite
IWASHITA, Y., YAMAMOTO, T., FURUITA, H., SUGITA, T. and SUZUKI, N. (2008), Influence of certain soybean antinutritional factors supplemented to a casein-based semipurified diet on intestinal and liver morphology in fingerling rainbow trout Oncorhynchus mykiss. Fisheries Science, 74: 1075–1082. doi: 10.1111/j.1444-2906.2008.01627.x
- Issue published online: 5 OCT 2008
- Article first published online: 5 OCT 2008
- Received 25 October 2007. Accepted 9 April 2008.
- antinutritional factor;
- Oncorhynchus mykiss;
- soybean meal
To investigate the cause of morphological changes occurring in the liver and intestine of rainbow trout Oncorhynchus mykiss fed defatted soybean meal (SBM)-based non-fish meal diets, morphological observations were conducted on fish fed casein-based semipurified diets supplemented with soybean antinutritional factors (soya saponin, soya isoflavone, soya lectin, oligosaccharide, Ca-phytate and their mixture). Hepatocytes and the epithelial cells in the hepatic ducts were not atrophied in any of the treatments. Lack of microvilli and pinocytotic vacuoles, and fatty degeneration of the epithelial cells were observed in the distal intestine of fish fed diets containing soya saponin. The proliferation of connective tissue in the mucosal folds and submucosa was shown in the distal intestine of fish fed the diet containing all substances including lectin. These results suggest that both saponin and lectin are the responsible factors in SBM for the occurrence of morphological changes of the distal intestine in rainbow trout fed SBM-based diets.