Haematological, biochemical and antibacterial response of andrographolide in Labeo rohita fingerlings

Abstract

Herbs and their active ingredients application in aquaculture sector have been an alternative strategy to counter chemotherapy. Andrographolide (EC 50 per cent), a diterpenoid lactone derived from the herb, Andrographis paniculata was used in the present study to evaluate its efficacy on haematological, biochemical profiles in Labeo rohita fingerlings. Fishes were fed with a diet containing 0.0 g per kilogram, 1.0 g.per kilogram, 2.0 g.per kilogram, 4.0 g.per kilogram and 8.0 g.per kilogram of andrographolide (EC 50 per cent) and were sampled on 14th, 28th, 42nd and 56th day for haematological and biochemical analysis. On 56th day blood samples were taken for analysis of haematological, biochemical parameters and challenge study was conducted by injecting Aeromonas hydrophila. In vitro antibacterial test was performed by using 0 mg per litre, 250 mg per litre, 500 mg per litre and 750 mg per litre of andrographolide (EC 50 per cent) through standard agar well diffusion method against fish pathogens such as P. aeruginosa, A. hydrophila and E. tarda. Biochemical and haematological parameters at the end of 42 days trial indicated that Andrographolide (EC 50 per cent) administered through feed significantly enhanced serum total protein, globulin, total erythrocyte counts and haemoglobin content. The survival rate was significantly high in experimental diet fed groups T2 followed by T1 and T3 when compared with control. The post challenge total leukocyte count, total protein, and globulin were higher in treated groups as compared to control group. The highest zone of inhibition (mm) 17, 11, 13 against P. aeruginosa, A. hydrophlila and E. tarda was recorded with 750 mg per litre andrographolide (EC 50 per cent). The results suggested that andrographolide (EC 50 per cent ) at the level of 2 g.kilogram exhibited stimulatory effect on haematological and biochemical parameters with increased disease resistance in L. rohita fingerlings against A. hydrophila infection.