Immunomodulatory effect of dietary nelumbo nucifera (lotus) in growth and haematology of cirrhinus mrigala challenged with pseudomonas aeruginosa.

The present study was carried out to evaluate the immunostimulant potential of Nelumbo nucifera (Lotus). Formulated diets with different concentrations of ethanolic extract of N.nucifera (D1=0%, D2=1% and D3=2%) were fed to Cirrhinus mrigala for 40 days, the Specific Growth Rate (SGR) and Feed Conversion Ratio (FCR) were calculated significant increase was observed in SGR &FCR. Then the experimental fishes were infected with Pseudomonas aeruginosa and after 5 days the haematological parameters like Total Erythrocyte count (TEC), Haemoglobin (Hb), Total leucocyte count (TLC), Differential leucocyte count (DLC), serum total protein, serum albumin and globulin levels were analyzed. The TEC, Hb, TLC, Lymphocytes and monocyte counts increased significantly in D3 diet fed fishes. Highly significant increase was observed in serum total protein and albumin levels only. Globulin levels remain unchanged. Basophil and Eosinophil counts decreased significantly. Thus N.nucifera in fish feed preparations may be included as growth promoter and immunostimulator.

Haematology of Cirrhinus mrigala fed with Vitamin C supplemented diet and post challenged by Aphanomyces invadens.

Disease outbreak in fish culture system interferes with productivity. Oral Immunostimulant containing vitamin C can result in activating the immune system in a nonspecific way thus providing resistance against pathogens. In the present study the fish Cirrhinus mrigala was fed with a feed supplemented with vitamin C (100mg/100g) for 40 days and post challenged with two different dilutions (102 and 105) of Aphanomyces invadans. The haematological parameters like TEC, TLC and differential leukocyte counts were analyzed 24hours, 72 hours and 7th day after infection. TEC counts and lymphocyte counts of infected fishes previously fed with control diet decreased significantly (43%, 36%) whereas it was minimal in fishes (21%, 8%) fed with Vitamin C supplemented diet. Post challenged fishes exhibited an increase in TLC in Vitamin supplemented diet (20%, 32%) over control diet fed fishes. In differential leucocyte counts the lymphocytes decreased in both the experimental groups (9%, 11%) whereas neutrophils increased in both, however the increase was higher in control diet fed group (34%). The basophils and eosinophils increased significantly in Vitamin C supplemented diet only (10%, 60%). Thus supplementation of feed with vitamin C enhanced fish’s tolerance to infection.