Efficacy of modified liquid panchagavya for production of zooplankton with reference to water quality

Abstract

The present study deals with the efficacy of modified liquid panchagavya for production of zooplankton in reference to water quality. The experiment was carried out with five different doses of liquid organic manure, modified liquid panchagavya at the different levels viz. 0.15% (T1), 0.20% (T2), 0.25% (T3), 030% (T4), 0.35% (T5), besides one control (T0) using fresh cow dung at the rate of 50g/ tank. Each treatment group was with 3 replicates. The experiment was conducted in glass aquarium of 56 l capacity for 6 weeks. The zooplankton production and water quality were observed at weekly intervals. During experimental period, the water quality parameters were found to be congenial for zooplankton growth. Ranges of water quality parameters were: water temperature: 23.39-23.53℃, pH: 7.4-8.5, Electrical conductivity (EC): 1.26-1.47 mS/cm, DO: 6.11-6.92 mg/l, total alkalinity: 109-151.05 mg/l, total hardness: 770.68-962.83 mg/l, TDS: 806.40-942.93 mg/l, nitrate-nitrogen: 1.49-2.66 mg/l, orthophosphate: 0.36-0.68 mg/l. Significantly (p< 0.05) higher plankton population and zooplankton biomass were found in T4 (748.43 No’s/l & 17.12 g/tank) followed by T3, T5, T2 and T1. The trend of dominant zooplankton categories observed by percent contribution in all treatments are Cladocerans (33%) followed by Copepods (30%), Nauplii (21%) and Rotifers (16%). From the study, it can be concluded that the use of 0.30% modified liquid panchagavya is most useful for zooplankton production to get good performance with aqua friendly effects on the rearing environment.