Evaluation of immunostimulatory properties of prickly chaff flower Achyranthes aspera in rohu Labeo rohita fry in pond conditions

Abstract

The immunostimulatory properties of seeds and leaves of Achyranthes aspera (Linn.) was evaluated in rohu Labeo rohita in the pond conditions. Rohu fry (1.9 ± 0.08 g) were introduced in nine hapas (25 hapa−1) set inside a pond. Two test diets enriched with 0.5% seeds (D1) and leaves (D2) of A. aspera and control diet (D3) were fed for 60 days. Then fish were immunized with chicken-RBC and blood and tissue samples were collected on days-7, 14 and 21 after immunization. The average weight was significantly (p < .05) higher in D1 diet fed rohu compared to other two feeding regimes. Specific growth rate and feed conversion ratio were maximum and minimum in D1 diet fed rohu. Serum lysozyme, myeloperoxidase and nitric oxide synthase levels were significantly (p < .05) higher in D1 diet fed rohu compared to others. This group was followed by D2 diet fed rohu. Significantly (p < .05) lower thiobarbituric acid reactive substances (TBARS) and carbonyl protein levels were found in D1 fed rohu compared to others. TBARS and carbonyl protein levels were also lower in D2 diet fed rohu compared to the control one. There were significant (p < .05) up-regulation of lysozyme C, lysozyme G and tumor necrosis factor-α (TNF-α) in hepatopancreas of rohu fed with D1 diet compared to others. This group was followed by the D2 diet fed rohu. The expression of lysozyme C was higher compared to lysozyme G regardless of feeding regimes. In enriched diets fed rohu, the expression of interleukin 10 (IL-10) was significantly (p < .05) lower compared to the control fish. Toll like receptor 4 (TLR-4) was significantly (p < .05) higher in D1 and D2 diets fed rohu compared to other two feeding regimes on day-7 and day-21 after immunization, respectively. Seeds and leaves enhanced the growth, induced the immune system of rohu and gave protection against oxidative stress in pond conditions. Seeds are more efficient compared to the leaves. The information generated from the field study has practical utility.