Abstract
As with other fishes farming, sturgeon farming depends on the use of well-balanced feed to maintain production. Commercial feeds available on the market are often based on soy protein, which, unfortunately, has many adverse effects on these fish. Therefore, alternative constituents are being sought that could be used in sturgeon fish farming. This study was designed to assess the feasibility of using diets containing white lupin meal at levels of 5% and 10% for juvenile Siberian sturgeon, compared to a formulated control group without lupin inclusion and a reference group fed commercial feed. Histological and immunohistochemical analyses were performed, combined with digestive enzyme activity assays. This study showed that feeding with white lupin meal did not adversely affect the rearing parameters, histology, or enzyme metabolism of sturgeons. An increase in the length of intestinal folds in the anterior intestine was observed in the group with 10% lupin meal inclusion, while this trend was not present in the spiral intestine, which may be indicative of a compensatory physiological mechanism when fish are fed less digestible feed. Antioxidative mechanism impairment was also noted in the two experimental groups. However, further research is still required to determine the possibility of using white lupin meal in the feeding of sturgeon fish, especially for more mature specimens.