Oviposition behaviour of Phlebotomus argentipes - A laboratory-based study

Abstract

online | memorias.ioc.fiocruz.brPhlebotomus argentipes, the vector of Indian kalaazar, has received much attention because of its transmission of Leishmania donovani (Mukhopadhyay & Mishra 1991). Surprisingly, very little information is available on the breeding habitats of P. argentipes. Consequently, the lack of information on the breeding of sandflies prevents us from locating these habitats and inhibits the targeting of prevention measures against the pre-imaginal stages of sandflies.To study sandfly biology and behaviour and to search for new methods of vector control, it is necessary to maintain large laboratory colonies of sandflies. In this respect, it is important to note that oviposition behaviour is a neglected aspect of the biology of sandflies. Pheromones influence oviposition behaviour in the females of haematophagous insects. These pheromones are produced by the ovipositing female or by conspecific eggs that co-occur with gravid females. Moreover, there has been no definitive information from laboratory studies of the oviposition of P. argentipes (Ghosh & Bhattacharya 1992, Dinesh et al. 2009, although it is thought that the insects select the oviposition site based on chemical factors released by the emerging progeny. It has been observed that in the wild, the behavioural ecology of P. argentipes is similar to that of Lutzomyia longipalpis (the corresponding South American vector) in terms of lek formation on the blood-feeding hosts, to which females are attracted. Dougherty et al. (1993), with the help of a bio-assay, demonstrated the semichemical-mediated oviposition attraction of gravid Lu. longipalpis. When determining the location of a suitable oviposition site for egg laying (Dougherty et al. 1993) or a potential host for blood feeding , haematophagous insects primarily use their olfactory senses. Previous research conducted by Elnaiem and Ward (1992) demonstrated that Lu. longipalpis preferred sites for oviposition that contain frass or rabbit faeces, which act as its larval rearing medium. More recently, Wasserberg and Rowton (2011) demonstrated that in choice and no-choice oviposition chambers, the effect of old sandfly colony remains (frass), conspecific eggs and their combination affected the oviposition rates of sandflies (Peterkova-Koci et al. 2012). The present study will contribute to the development of a methodology for the maintenance of sandfly colonies, which is a major challenge for scientists working on different biological aspects of sandflies. Additionally, this study may provide promising tools for the monitoring and control of target insects using integrated vector management strategies involving the use of traps baited with pheromones, infusions and insecticides. In the present study, experiments were conducted in Hilton's pots that contained old remains of colonies, including eggs, larvae and larval foods, with empty pots serving as the control group. Hence, in the present study, an attempt was made to observe the possible role of pheromone/odour in the oviposition beha...

Studying DDT Susceptibility at Discriminating Time Intervals Focusing on Maximum Limit of Exposure Time Survived by DDT Resistant <i>Phlebotomus argentipes</i> (Diptera: Psychodidae): an Investigative Report

“…This study objective adds to an attribute for an urgent need of change in rhetoric form of the WHO protocol for susceptibility estimation among highly resistant P. argentipes. (15) and rearing under the controlled conditions of the insectarium with stable temperature and relative humidity of 28 2 C and 80 5 respectively with 12 h of light dark cycles (19)(20)(21)(22)(23). Additionally, the nonresistant sand flies serving as control samples for the bioassay test were procured from the general colony of P. argentipes being reared under the controlled environment of insectarium of this research institute.…”

Intensely clustered outbreak of visceral leishmaniasis (kala-azar) in a setting of seasonal migration in a village of Bihar, India

“…This could be possible if the brick kilns employing migrants from kala-azar endemic areas have presence of P. argentipes vector and are close to permanent human settlements located within the vector's flight range [26]. Although high vector density at brick kilns could be less likely due to the unique requirement of damp, organic rich conditions for their oviposition and breeding [37], this needs entomological exploration at those brick kilns with seasonal migration from kala-azar endemic districts.…”

Monitoring Susceptibility Status of Phlebotomus argentipes (Diptera:Psychodidae) at Bihar (India) for the Procurement of Homozygous DDT Resistant Colony

“…The captured sand flies were released into the wooden-framed, wiremeshed, cloth-lined barraud cage (42×36×36 cm) for their adjustment to the new environment of insectary of Vector Biology and Control Division, Rajendra Memorial Research Institute of Medical Sciences (ICMR), Agamkuan, Patna, after which the Phlebotomus argentipes (Diptera: Psychodidae) were sorted out with the help of provided identification key [20]. Only healthy and strong individuals were retained for colonizing purpose after offering blood meal to female P. argentipes [21][22][23]. Briefly, the sand flies were transferred to the clean and dried wooden-framed, wire-meshed, cloth-lined and glassscreened feeding cage (132x36x36 cm).…”

“…This enhances the blood feeding percentage. On completion of feeding process, single blood-engorged female along with a male sand fly as a parent generation for forthcoming filial generations (F-generations) were selected and confined in each 20 plaster-lined Hilton pots (7×7 cm) with meshed lid, purposely made for oviposition by female sand flies [22]. The female sand flies were allowed to oviposit on the plastered surface of Hilton pots that were kept on damp cloth for providing uninterrupted supply of relative humidity 80 ± 5% under the controlled condition of insectorium maintained at temperature 28 ± 2°C; 12 hrs (L:D).…”

“…Eggs were morphologically identified and counted under stereoscopic microscope (Carl Zeiss Stereoscopy Microscope, Austria; Model 426126) to avoid potential contamination with larvae of foreign insects, mites. The eggs were reared to the adult parent generation in accordance with earlier described protocol for rearing sand flies in controlled conditions [21][22][23][24]. The emerging neonates were then fed with anti-fungal larval food comprising ground rabbit faeces mixed with sand in 2:1 ratio [23].…”