Combined effects of leucas aspera, oxy-cyclodextrin and bentonite on the growth, serum biochemistry, and the expression of immune-related gene in nile tilapia (Oreochromis niloticus)

This study investigated the effects of a combination of Leucas aspera, Oxy-cyclodextrin and sodium bentonite (LOB) on growth, digestive enzyme activity, innate immune response, haematology, and expression of immune-related genes in Nile tilapia. A total of 240 juvenile fish (20.15±0.05g) were randomly distributed into four dietary groups in triplicate and fed respective diets containing a graded level of LOB at 0 g kg-1 (Control), 0.3 g kg-1 (T1), 0.6 g kg-1 (T2) and 0.9 g kg-1 diet (T3) for 60 days. After 60 days, higher growth was observed in fish fed T2 diet (P < 0.05). Digestive enzyme activities and innate immune parameters were significantly higher in T3 group. Some of the haematological parameters reported statistically higher counts in T2 group (P < 0.05), whereas erythrocyte indices and WBC counts were significantly higher in T3 group. Liver-kidney activities were recorded low in T3 group. Urea and creatinine were higher in control group, whereas T2 group recorded the least value. The highest relative expression of IL-1β, IgM-heavy chain, TGF-β and IFN-γ were recorded in T2 group, but TNF-α was upregulated in T3 group. The results showed that 0.6-0.9 g kg-1 of LOB is recommended for inclusion in diet.