Browsing by Author "Gunathilaka, RAKM"

Now showing 1 - 3 of 3

Distribution of Phlebotomus argentipes Annandale & Brunetti, 1908 in the Anuradhapura district, North Central Sri Lanka
(Wolters Kluwer, 2023) Nayakarathna, NMNG; Gunathilaka, RAKM; Ganehiarachchi, GASM
Background & objectives: Phlebotomus argentipes Annandale & Brunetti, 1908 (Diptera: Psychodidae) is the main vector responsible for the transmission of Leishmania donovani (Laveran & Mesnil, 1903) Ross, 1903 in the subcontinent of India. It is the potential vector of cutaneous leishmaniasis in Sri Lanka. The present study determined ecological factors that influence the abundance of P. argentipes in areas with high disease prevalence in the Anuradhapura district, North Central Sri Lanka. Methods: CDC light traps and yellow sticky traps were used for sampling, and abundance was recorded throughout 12 months with selected environmental parameters namely, relative humidity, wind speed, and temperature. The relationships between the abundance of P. argentipes with mean temperature, % relative humidity, and wind speed were tested with regression analysis. The temporal distribution of the vector population was tested with a time series analysis. Results: The study identified the most preferable microhabitats of P. argentipes: shrubs, unclear areas, gardening areas, wet soil areas with leaf litter, and termite hills. The results indicated that the abundance of P. argentipes was highly dependent on mean temperature (P = 0.00, R2 = 68%), and a high number of P. argentipes was recorded for a low mean temperature range of 24.7–27.3°C. Furthermore, the abundance of P. argentipes exhibited an increasing trend with high humidity levels of 72–88% (P = 0.00, R2 = 91.6%). Interpretation & conclusion: These findings may help predict the temporal variation of the potential vector population with studied ecological parameters and contribute to a successful vector management strategy with thorough knowledge of the behavioral pattern of P. argentipes.
Effect of oviposition-site deprivation on reproductive performance and life history parameters of dengue vector Aedes aegypti†
(National Science Foundation of Sri Lanka, 2023) Gunathilaka, RAKM; Ganehiarachchi, GASM
Dengue and dengue haemorrhagic fever constitute one of the most significant arthropod-borne viral diseases that occur in tropical and subtropical regions in the world. Annually 390 million new dengue cases are being reported from the 128 dengue-endemic countries. Aedes aegypti is the primary vector that transmits the disease. Since the primary vector is a container breeder, source reduction appears to be a good vector control method. Source reduction limits the oviposition of females through oviposition-site deprivation. Therefore, the current study was conducted to determine the effect of oviposition-site deprivation on the fecundity, fertility, life-history parameters, and longevity of Ae. aegypti. Oviposition-site deprivation was enabled by delaying the access to the oviposition substrate. Female mosquitoes were allowed to access the oviposition substrate separately on the day of blood feeding and 2, 4, 6, and 8 days after blood feeding. The results showed that oviposition-site deprivation significantly increased fecundity with an increase in the number of egg retention days. The number of eggs laid by the female increased by 69% when the female was compelled to retain the eggs for 8 days. The highest recorded fecundity was 100 ± 5. Nevertheless, fertility, percentage larval mortality, total larval duration, pupal duration, and longevity were not affected by the number of egg retention days. Thus, it is imperative to have a clear awareness about the effect of oviposition-site deprivation on the reproductive performance of the vector mosquitoes when adopting vector control strategies.
Use of a cost-effective artificial feeding system to evaluate the effect of blood meal source and its role in feeding success, reproductive parameters and larval growth of laboratory-reared Aedes Aegypti (L.)
(International Journal of Mosquito Research, 2022) Ashani, MLS; Gunathilaka, RAKM; Ganehiarachchi, GASM
Five different blood sources, human, cattle, rabbit, sheep and dog were delivered to laboratory-reared Aedes Aegypti to determine the effect of blood meal source on reproductive performance and larval growth characteristics of the mosquitoes. The blood meal was delivered with the use of a cost-effective artificial membrane feeding system. The mosquitoes displayed a significant feeding success for human blood over the other given blood meal sources. Thus, significantly a higher fecundity for human blood followed by cattle blood over other given blood meal sources was observed. The mean percentage of egg hatching for human blood and cattle blood was more or less the same, while the values were significantly different from that of other given blood meal sources rabbit, sheep and dog. Furthermore, larval growth parameters did not show any significant relationship with the blood meal source. These findings agree with established literature and facilitate the rearing and maintaining of Ae. Aegypti mosquitoes in a cost-effective manner. Hence the findings of the study aid in empowering laboratory research on Ae. Aegypti cost-effectively while enabling studies on its biology in in vitro conditions which are crucial in implementing disease control strategies.