title: Immune response in the tilapia, Oreochromis mossambicus on exposure to tannery effluent.
abstract: The objective of the study was to investigate the effect of chronic exposure to sublethal concentrations of tannery effluent (TE) on the specific immune response and nonspecific immunity in tilapia, Oreochromis mossambicus. The effluent from the tannery was collected directly from a chrome-tanning factory situated in Dindigul district, Tamil Nadu, India. Apart from chromium (88.2 ppm), the effluent contained appreciable amount of calcium carbonate and sodium sulphate. Groups of fish (45-50 g) were exposed to 0.0053, 0.053 or 0.53% [0.1%, 1% or 10% LC50] of TE for 28 days. The specific immune response of fish was assessed by antibody response to heat-killed Aeromonas hydrophila by ELISA and bacterial agglutination assay. Nonspecific immune mechanisms were assessed in terms of serum lysozyme activity, production of intracellular reactive oxygen species (ROS) and reactive nitrogen intermediates (RNI) by peripheral blood leucocytes (PBL). The results indicate that chronic exposure of fish to 0.53% of TE, significantly suppressed antibody response, nonspecific serum lysozyme activity, and ROS and RNI production. Exposure to 0.053% (1% LC50) of TE also caused a similar suppressive effect though at a lesser degree. In conclusion, the study shows, that exposure to sublethal concentrations of TE, can lead to adverse effects on selected immune reactions in tilapia. Further, these findings may be important in terms of monitoring fish health and risk assessment during periods of fluctuating levels of pollutants in the natural and farm environments.
authors.affiliation: Centre for Fish Immunology, Postgraduate and Research, Department of Zoology, Lady Doak College, Madurai-625 002, Tamil Nadu, India.
authors.forename: M
authors.initials: M
authors.lastname: Prabakaran
authors.forename: C
authors.initials: C
authors.lastname: Binuramesh
authors.forename: Dieter
authors.initials: D
authors.lastname: Steinhagen
authors.forename: R
authors.initials: R
authors.lastname: Dinakaran Michael
mesh_terms: D016980:Aeromonas hydrophila / Q000276:immunology; D000372:Agglutination Tests; D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood; D000917:Antibody Formation / Q000187:drug effects*; D002119:Calcium Carbonate / Q000032:analysis; D002478:Cells, Cultured; D002857:Chromium / Q000032:analysis; D004305:Dose-Response Relationship, Drug; D004784:Environmental Monitoring / Q000379:methods; D004797:Enzyme-Linked Immunosorbent Assay; D029941:Fish Proteins / Q000097:blood; D005618:Fresh Water / Q000737:chemistry; D007111:Immunity, Cellular / Q000187:drug effects*; D007194:India; D007962:Leukocytes / Q000187:drug effects / Q000378:metabolism; D009113:Muramidase / Q000097:blood; D026361:Reactive Nitrogen Species / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism; D013431:Sulfates / Q000032:analysis; D013633:Tanning; D017210:Tilapia / Q000276:immunology* / Q000378:metabolism; D013997:Time Factors; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000633:toxicity*
chemical_list: D000907:Antibodies, Bacterial; D029941:Fish Proteins; D026361:Reactive Nitrogen Species; D017382:Reactive Oxygen Species; D013431:Sulfates; D014874:Water Pollutants, Chemical; D002857:Chromium; C012036:sodium sulfate; D009113:Muramidase; D002119:Calcium Carbonate