Differences in Haematological Parameters in Normal, Infected and Immune-Primed Fingerlings of Red Tilapia (Oreochromis mossambicus x Oreochromis niloticus)
Ali Muhammad Mastoi*, Mithun Sukumaran*, Anila Mastoi**, Anuar Hussan*, Faizah Shaharom* and Anil Chatterji*
Journal Title:Biological Forum-An International Journal
ABSTRACT : Infectious diseases are always a major problem causing heavy loss to the fish farmers. The fingerlings of red tilapia (Oreochromis mossambicus x Oreochromis niloticus) were fed with extracts prepared either by acid hydrolysing process or ethanolic extracts from oyster (Saccostrea cuccullata; Born, 1778) and seaweed (Sargassum baccularia; Mertens). These extracts were mixed at different concentrations in commercial diet and fed to the fingerlings till 15 days. All groups of fishes fed with experimental and normal diets were challenged by a gram-negative bacterium (Aeromonas hydrophila) to see the effects of pathogen. Fishes fed with experimental feed consisting of ethanolic extract of oyster showed better survival as compared to other experimental feeds. Maximum total leucocytes (22 + 43 × 103 cell/mm3) and erythrocytes (32 + 33 × 106 cells/ mm3) were recorded in fishes fed with ethanolic extract of oyster (P < 0.05) which were similar to fishes of control group. Significant (P < 0.05) changes were also observed in the haematological parameters such as; lymphocyte, neutrophil, monocyte and basophil cells in feed incorporated with ethanolic extract of oyster. Similarly, higher values of albumin; amylase; total cholesterol; GGT; glucose; phospholipids; triglycerides; total serum protein; lactase, LDH and lipase in the infected fish were observed as compared to the control group (p < 0.05). Fishes fed with ethanolic extract showed relatively much closer values as observed in control group. Our results strongly suggest that ethanolic extract of oyster (S. cuccullata) could combat the microbial infection by stimulating the non-specific immune response effectively at fingerlings stage of red tilapia.