Seasonal variation in immune organs and immune response of catfish Arius maculatus in Parangipettai coastal area

Different non-specific immune parameters and their seasonal changes in spotted Catfish Arius maculates from Vellar estuary was investigated. It was undertaken for a year which included four main seasons of a year such as summer (April-June), Pre Monsoon (July-september), Monsoon (October-December) and Post Monsoon (JanuaryMarch). The Physico-chemical parameters (Temperature, pH, Salinity and Rainfall) of Vellar estuary and Non specific immune response (WBCs, Lysozyme and superoxides) and histological differences of the candidate species were observed during the different seasons. The results of physic-chemical parameters stated that the range was higher in summer and lower in Monsoon season except rainfall. White blood cells count (WBCs) and Serum lysozyme and myeloperoxidase activities were lower (6.2±0.1 and 960±61, respectively) in Monsoon as compared to any other season of the year. The NBT activity was higher (0.65±0.021) in Monsoon season and lower in summer. In Histology, the Melano Macrophage Centers and WBCs were densely packed in summed and loosely packed in Monsoon season. This study indicated that certain non-specific immune parameters of this species can be modulated at certain times of the year.