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The present research aims to evaluate the effects of ammonium (NH4+), nitrate (NO3–) and phosphate (PO4–3) on oviposition preference, hatching rate, time to pupation, pupation rate, time to adult emergence, adult emergence rate and female to male ratio of Culex quinquefasciatus mosquito, under laboratory conditions. The mosquito preferred to oviposit in containers containing 5 ppm NH4+, 45 ppm NO3– or 30 ppm PO4–3 solution. No significant effect of these polutants on egg hatching rate was observed. The larvae that existed in containers containing 5 ppm NH4+, 45 ppm NO3– or 30 ppm PO4–3 solution reached earlier to pupal and adult stages. The presence of NH4+ (5 ppm), NO3– (45 ppm) or PO4-3 (30 ppm) in aqueous medium, resulted in decreased time to pupation or adult emergence and increased pupation and adult emergence rates. The adults emerged from these larvae showed significantly higher female to male ratio as compared to control adults (P<0.05). From the findings of the present research, it is concluded that the levels of NH4+, NO3– or PO4–3 set in effluents for wastewater reuse in agricultural irrigation by WHO (2006) are favorable for the survival and development of Cx. quinquefasciatus mosquito, however higher levels of NH4+, NO3– or PO4–3 are not favorable for the survival and development of this mosquito. These results help in identification of concentration ranges of the ammonium, nitrate and phosphate that make the larval habitat favorable for survival and reproduction of Culex mosquitoes. This could be helpful in effective control of mosquito borne diseases. [ABSTRACT FROM AUTHOR]

During the present research, the predatory efficiency of nymphs of six coexisting odonate species i.e., I. elegans, T. aurora, P. flavescens, L. fulva, S. decoloratum and C. servilia was studied by using the 3rd instar larvae of Cx. quinquefasciatus as prey. Among the odonate species, there was observed variation in the daily feeding rate. The highest number of mosquito larvae was ingested by the P. flavescens nymph (47.0 ± 5.1 mosquito larvae/day). The predation performance of the odonate nymph was also compared between the day and night times. The feeding rate of nymphs of most odonate species was significantly higher during the daytime as compared to night-time (P ≤ 0.05). During the present research, feeing rates of odonate nymphs on Cx. quinquefasciatus 3rd instar larvae were also studied under varied condition of prey and predator density and water volume. Feeding rate of nymphs of each odonate species was positively correlated with increase in predator and prey density but was negatively correlated with increase in water volume. During the present research, odonate nymphs i.e., I. elegans, T. aurora and P. flavescens were exposed to various concentration of NH4+ and NO3- in the laboratory for seven days. Nymph of P. flavescens species was found least sensitive to both, NH4+ and NO3-. From the findings of the present research it was concluded that P. flavescens species is more efficient predator of Cx. quinquefasciatus 3rd instar larvae and is highly resistant to increasing water level of NH4+ and NO3. [ABSTRACT FROM AUTHOR]

The present study was conducted to evaluate the association between residues of α- endosulfan, β-endosulfan, endosulfan sulfate and total endosulfan (Σ endosulfan) with serum cholesterol, alkaline phosphatase (ALP) and total proteins (TP) in diagnosed cancer patients and healthy subjects of Karachi, Pakistan. Donors provided fasting blood samples with informed consent and serum was separated within two hours of blood collection through centrifugation at 2500 rpm. Levels of serum cholesterol, ALP and TP were quantified on Roche/Hitachi spectrophotometers while gas chromatograph (GC-17A) coupled with 63Ni electron capture detector was used for the quantification of endosulfan residues. Detected mean concentrations of α-endosulfan, β-endosulfan and endosulfan sulfate were higher in the cases compared with controls (p ˃ 0.05). Mean levels of serum cholesterol and TP were found significantly reduced in the cancer cases (p < 0.05) while ALP activity was found significantly elevated in the cancer cases compared with controls (p < 0.05). An association between endosulfan sulfate and cholesterol levels (r = 0.333) and between Σ endosulfan and cholesterol (r = 0.245) was detected in the cancer cases but no such association was found in the control group. The presence of higher serum concentrations of α-endosulfan, β-endosulfan, endosulfan sulfate and Σ endosulfan associated with abnormal serum biochemical parameters may be a risk factor of various malignancies in humans. [ABSTRACT FROM AUTHOR]