Effects of Single and Combined Supplementation of Dietary Probiotic with Bovine Lactoferrin and Xylooligosaccharide on Hemato-Immunological and Digestive Enzymes of Silvery-Black Porgy (Sparidentex hasta) Fingerlings

The aim of this study was to evaluate the effects of different levels of dietary Lactobacillus plantarum as probiotic (Pro) with bovine lactoferrin (LF) and xylooligosacharide (XOS) on growth performance, hemato-immune response, body composition, digestive enzymes activity and expression of immune-related and growth-related genes of sobaity (Sparidentex hasta) for 8 weeks. Fish were fed with feed including: control diet (no LF, XOS and pro inclusion), diet 1 (400 mg kg⁻¹ LF + 5000 mg kg⁻¹ XOS), diet 2 (400 mg kg⁻¹ LF + 10000 mg kg −1 XOS), diet 3 (400 mg kg⁻¹ LF + 1 × 106 gr⁻¹ Pro (L. plantarum)), diet 4 (800 mg kg⁻¹ LF + 5000 mg kg ⁻¹ XOS), diet 5 (800 mg kg⁻¹ LF + 10000 mg kg⁻¹ XOS), diet 6 (800 mg kg⁻¹ LF + 1 × 106 gr⁻¹ Pro (L. plantarum)). Growth performance, hematological parameters (except for white blood cell counts), body composition and immune-related gene expression were not affected by different experimental groups (p>0.05). Nonetheless, non-specific immune response (except for total immunoglobulin) and growth-related gene expression of treatments and control group significantly varied (P<0.05). Digestive enzymes activity including total protease and amylase increased by supplementing diets with different combinations of immunostimulants (P<0.05). Our results suggest that diets supplemented with selected levels of LF, XOS and L. plantarum could not improve growth performance, body composition and hemato-immune response, but improved digestive enzyme activities in S. hasta fingerlings.