Beta-conglycinin and gut histology of sunshine bass fed diets with new varieties of non-GM soybeans

Authors: RAMENA, YATHISH - University Of Arkansas At Pine Bluff; Lange, Miles; Rawles, Steven - Steve; LOCHMANN, REBECCA - University Of Arkansas At Pine Bluff; CHEN, PENGYIN - University Of Arkansas; GAYLORD, T. GIVSON - Us Fish And Wildlife Service; McEntire, Matthew - Matt; Beck, Benjamin; Farmer, Bradley; Barrows, Frederic

Submitted to: Aquaculture America Conference
Publication Type: Abstract Only
Publication Acceptance Date: 10/2/2015
Publication Date: 2/22/2016
Citation: Ramena, Y., Lange, M.D., Rawles, S.D., Lochmann, R., Chen, P., Gaylord, T., Mcentire, M.E., Beck, B.H., Farmer, B.D., Barrows, F. 2016. B-conglycinin and gut histology of sunshine bass fed diets with new varieties of non-gm soybeans. [abstract]. Aquaculture America Conference. p. 654.

Interpretive Summary: Traditional soybean meal contains modest levels of protein and high levels of anti-nutritional factors that reduce their digestion and utilization by fish. For example, certain soybean proteins, like Beta-conglycinin, can cause inflammation of the intestine and stimulate the release of a hormone that suppresses food intake in fish. We are studying the effects of meals made from new strains of non-genetically modified (non-GM) soybeans with high protein and reduced anti-nutritional factors on hybrid striped bass (Morone chrysops x M. saxatilis) nutrient retention, immune response and changes in the structure of the intestine. Control diets were formulated either with fish meal or soy protein concentrate as positive controls or with Ozark soybean meal as a negative control; Ozark is the parent variety from which the non-GM soybeans in this study were derived. The test diets were formulated so that all fish meal protein was replaced with one of the soy products, including the three new non-GM varieties (R05-1415, R05-1772, or R07-2001). Intestine and blood serum samples were collected from the initial fish that had never been exposed to soy (i.e., "soy naïve" fish) as well as fish at the end of the 10-week feeding trial. The samples are being analyzed for immune response to Beta-conglycinin and any changes in the gut structure (gut enteritis) due to soy antigens. The results will be presented at the meeting.

Technical Abstract: It is reported that the soybean protein (Beta-conglycinin) might cause inflammation of the distal intestine and stimulate endogenous cholecystokinin release that suppresses food intake in fish. We are studying the effects of meals made from new strains of non-GMO soybeans with high protein and reduced anti-nutritional factors (ANFs) on Sunshine bass (Morone chrysops x M. saxatilis) nutrient retention, immune response to Beta-conglycinin, and gut histological changes in the proximal and distal intestine. The hypothesis is that new non-GMO soybeans with fewer anti-nutritional factors (ANFs) will result in improved fish gut epithelium (proximal and distal) compared to standard soybean meal, which should permit higher inclusion rates of soybean meals in hybrid striped bass diets and reduce reliance on fish meal. The control diets were formulated either with fish meal or soy protein concentrate as a positive control or with Ozark (parental variety) as a negative control. All the test diets were formulated so that 100 percent FM protein was replaced with one of the non-GM soybean meal (R05 1415 SBM, or R05 1772 SBM, or R07 2001). The gut and serum samples were collected from the initial soy naïve fish for gut histology and soy antigen. Four hundred fifty sunshine bass (5g Ave. wt.) were stocked in 18 randomly assigned tanks (N=25, 3 tanks per diet). Fish were fed twice daily to apparent satiation for ten+ weeks. At the end of the trial, the gut and serum samples were collected from the fish. The samples are being analyzed for the immune response to Beta-conglycinin and any changes in the gut histology (gut enteritis) due to soy antigens. The results will be presented at the meeting.