Biochemical parameters in the blood of gilthead sea bream (<italic>Sparus aurata</italic> Linnaeus, 1758) supplemented with commercially available β‐glucan‐based product (IMUNO‐2865®).

Abstract: The aim of this study was to evaluate the effects of a promising new immune stimulant in aquaculture (IMUNO‐2865^®) on biochemical parameters in sea bream during the winter stress period. A total of 640 sea bream were fed throughout 90 days with diets containing 0 (Group 1), 1 (Group 2), 10 (Group 3) and 25 g (Group 4) of IMUNO‐2865^® kg⁻¹ of feed. Samples were taken each month and 90 days after supplementation. No statistical differences among treatment groups were noticed for the following biochemical parameters: glucose (GLU), aspartate aminotransferase (AST), plasma cholesterol (CHOL), lactate dehydrogenase (LDH), urea (URE) and creatinine (CREA). At the final sampling, total ammonia (NH₃) was higher in Groups 3 and 4 compared to the control and the low supplementation group (<italic>p</italic> < .05), while total proteins (TP) was significantly higher in Group 4 compared to all other groups, and in Groups 2 and 3 compared to the control group (<italic>p</italic> < .05). Blood Ca⁺⁺ levels were significantly higher after 60 days of feeding in all treatment groups compared to the control, and remained elevated in Group 4 even after 90 days following cessation of supplementation (<italic>p</italic> < .05). The results of this study described the increase of biochemical parameters in the blood of sea bream after use of IMUNO‐2865^® but future research is needed to evaluate its potentially immunostimulative effect on fish in commercial aquaculture. [ABSTRACT FROM AUTHOR]