UTTAR PRADESH JOURNAL OF ZOOLOGY

Today fish and fisheries are pivotal in food security, meeting the social objectives in terms of sustenance of semi skilled personnel by providing employment and in contribution to large export earnings Even though profitable, this sector also faces several constraints such as misapplication of husbandry and disease management, collection of seed and use of fishery resources as feed inputs, habitat alteration, nutrient enrichment, pesticide residue etc. Among these, fish diseases have been known to cause the largest economic loss in aquaculture which has forced many farmers to abandon aquaculture and change to other professions. Hence, it was thought worthwhile to analyse the microbial quality of the water present in the system for the four seasons of the year. The bacterial counts varied from 4.1 x 10⁴cfu/ml to 11.2 x 10⁵cfu/ml. The minimal count was noticed in April and the maximal count in November during both the years of study. The fungal load in the water was found to range between 1.3 and 5.6 x 10² during the years of study. The minimal load was uniformly noticed in July for both the years even though it was also noticed in June during the second year. The maximal load, however, was uniformly noticed in January for both the years.

A total of 9 bacterial species belonging to 8 genera could be isolated. Of these, 7 belonged to Gram negative bacteria and 2 were Gram positive bacteria. Among the 7 Gram positive bacteria, only 3 species were recorded in all the four seasons of the year (Escherichia coli, Proteus vulgaris and Pseudomonas aerugniosa) while the remaining were seasonal. Among the 2 Gram positive bacteria, only Streptococcus faecalis was present in all the seasons. A seasonwise comparison reveals that all the 9 species occurred in the system during the rainy/winter season while during the presummer, only 7 species were present. Salmonella typhi and Klebsiella pneumoniae were absent during this season.  During the summer season, only 5 species were recorded. Enterobacter aerogenes, Salmonella typhi, Staphylococcus aureus and Vibrio alginolyticus were not recorded in this season. The post summer season recorded the presence of 6 species with Salmonella typhi, Staphylococcus aureus and Vibrio alginolyticus being absent during this season. A total of 10 species of fungi belonging to 8 genera were recorded. A comparison of the fungal diversity during the different seasons reveals that 9 species were recorded during the rainy season. Only Penicillium notatuim was absent during this season. On the other hand, the presummer season recorded 8 species with Pythium undulatum and Saprolegnia diclina being absent in this season. The summer season recorded the presence of 7 species. Aspergillus fumigatus, Achlya apiculata and Saprolegnia diclina were absent during this season. The post summer season recorded the presence of 6 species. Aspergillum fumigatus, Chaetomium globosum, Fusarium oxysporum and Penicillium notatum were absent during this season. Thus among the 10 species, only 3 species were recorded in all the seasons (Aspergillus niger, Aspergillus flavus and Trichoderma viride). The present study reveals the presence of potentially pathogenic micobes in the system which in turn reflects on the need to curb their population necessitating the need to creating awareness among the potential handlers of the system.