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.