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Background: Sub-lethal toxicity bioassay experiments were conducted to determine the toxicity of glyphosate herbicide on Koi carp, Cyprinus carpio fingerlings. Koi carp fingerlings with mean length 8.06 ± 0.99 cm were obtained from a freshwater fish seed hatchery of the university.Methods: The fishes were exposed to sub-lethal concentrations i.e. 1/10th (3.6 mgL-1) and 1/5th (6.6 mgL-1) of glyphosate. Oxygen consumption rate, Ammonia-Nitrogen excretion rate, Oxygen:Nitrogen ratio and food consumption rate were recorded after every 7 days for a period of 28 days.Result: Results indicated significant decrease (P less than 0.05) in oxygen consumption in 1/10th and 1/5th of LC50 concentrations. Ammonia-Nitrogen significcantly increased in exposed fishes. Oxygen : Nitrogen ratio and food consumption rate also significantly decreased (P greater than 0.05) in treated fishes. The results indicated that glyphosate had impacts on exposed fish, hence, the need of regulation of its usage to protect non-targeted species and the environment.

The present study deals with physico-chemical parameters and their correlation coefficient of Ambawade reservoir, Raigad [M.S] India during February 2014 to January 2016. The range of various parameters of reservoirs atmospheric temperature from 25.3ºC to 36.4ºC, water temperature from 23.5 to 35.7ºC, pH from 5.80 to 8.40, DO from 4.56 to 8.32 mg L-1, transparency from 32.56 to 103.40 cm, Free CO2 from nil to 5.90 mg L-1, EC from 58.20 to 110.80 µS cm-1, TDS from 8.41 to 18.42 mg L-1, total hardness from 54.40 to 71.32 mg L-1, total alkalinity from 46.32 to 74.21 mg L-1, NO3 - -N from 0.378 to 1.024 mg L-1, PO4 -P from 0.041 to 0.310 mg L-1, SiO2 from 3.75 to 9.19 mg L-1, Mg2+ from 5.67 to 8.84 mg L-1, Na+ from 3.04 to 5.66 mg L-1 and K+ from 0.36 to 0.98 mg L-1. Correlation coefficient (r) showed high significant positive and negative relationship (p < 0.01 level) between the parameters. The results revealed that there was a fluctuation in physico-chemical parameters during the period under report.

Five live or inert food organisms (adult Artemia, Moina, Tubifex worms, clam meat, poultry egg custard) were evaluated as feed for postlarvae of Macrobrachium rosenbergii. The postlarvae (avg 5.2±0.22 mg, 7.2±0.38 mm) were reared in plastic pools (0.9 m diameter x 0.6 m) contain- ing 100 l fresh water, stocked at one postlarva per liter for 30 days, with five replicates of each treatment. There were significant differences (p