Some reproductive studies in Clarias batrachus with reference to different thermal conditions

Eco-physiological study indicates the Clarias batrachus is a eurythermal fish and able to tolerate the wide range of climatic conditions. The quantitative analysis of nutritional components in gonadal region, such as glucose, proteins and fats showed the variations during exposure of fish to hot and cold temperatures. The fresh water catfish exhibits distinct phases of reproduction and also showed the changes in the levels of energy precursors with change in the excretory products, with respect to adaptability towards different environmental temperature conditions. Gradual increase of glucose, proteins, and cholesterol is observed in the male gonadal tissues. Rectal gland and clasper tissues showed, decreased of urea levels during the exposure of fish to the higher tolerable temperature. However, in female fish, the levels of proteins are significantly enhanced during the high temperature exposure. The levels of urea significantly decreased in the tissues of uterus and brain during the study period, while the lowering of glucose levels in brain indicates the extent of rate of physiological activity of the brain

Nutrient dynamics in relation to discharge of sewage in Winganga River water at Pauni, District Bhandara (M.S.), India

The significant sources of organic pollution enhance nutrient contents in the river water. Nitrogen, phosphorous and silicates play very important role in the biological activities of aquatic environments, such as the abundance of vegetation and faunal status. The Wainganga river water at Pauni town is analyzed for nutrient concentrations their inputs and rate of assimilation by organisms. Phosphate concentration ranged from 0.91 mg/l to 2.29 mg/l, ammonia nitrogen ranged from 0.32mg/l to 1.48 mg/l , nitrate nitrogen ranged from-, nitrite from 2.88 mg/l to 7.64 mg/l.

Zooplankton abundance and its correlations with physico-chemical parameters from urban lakeWani, Dist. Yeotmal, Maharashtra.

Some physico-chemical and biological parameters were studied from urban lakeWani, distYeotmal to assess the pollution status. The parameters were studied for the period of one yeari.e. from July 2006 to June 2007. The sample analysis showed great diversity in zooplankton, consisting 65 genera belonging to five groups. The seasonal succession of zooplankton was in the order of summer>winter>monsoon. The physico-chemical parameter such as temperature, pH, CO2, TDS, DO, Sulphate, phosphate have been studied. The correlation analysis was also made between zooplankton and physico-chemical parameter