Diversity and breeding sites of mosquitoes (Diptera, Culicidae) potentially vectors of arboviruses in Belgian equestrian farms

Poster (2012, October 08)

This study aims to determine the potential importance of the livestock farms, especially equestrian, to welcome and favor the proliferation of certain species of mosquito responsible for transmission of ... [more ▼]

This study aims to determine the potential importance of the livestock farms, especially equestrian, to welcome and favor the proliferation of certain species of mosquito responsible for transmission of arboviruses. The study of biodiversity of Culicidae in the horse farms in Belgium is carried out on species sampled at 64 biotopes in six stations study. Five surveys were realized during 2011 (June, July, August and October) and one in 2012 (June). The morphotaxonomic and molecular study of mosquitoes collected showed the presence of ten species: Culisata annulata Schrank, 1776; Anopheles claviger s.s. Meigen, 1804; An. maculipennis s.s. Meigen, 1818; An. messae Falleroni, 1926; Culex pipiens molestus Forskal, 1775; Cx. pipiens pipiens Linné, 1758; Cx. torrentium Martini, 1925; Cx. hortensis hortensis Ficalbi, 1889; Cx. territans Walker, 1856 and Coquillettidia richardii Ficalbi, 1889. Among the 24893 individuals examined in 2011, Cx. pipiens sl and Cx. torrentium represent 68.00% and 22.38% respectively of total harvest. These last species with Cs. annulata, are dominants and ubiquitous in all the horse farms visited. The species of the genus Anopheles have strong ecological requirements and are therefore associated with some special habitats; other species however have a strong ability to adapt and therefore attend a wide variety of biotopes (Cx. pipiens, Cx. torrentium and Cs. annulata). At the horse farms, water troughs and ponds are the most favorable habitats for larval development of Culicidae. The species potentially vectors of arboviruses that can cause problems in epidemiological equestrian farms are Cx. pipiens sl, Cx. torrentium and Cs. annulata. [less ▲]

Laboratory and field preliminary tests of Metarhizium anisopliae formulated with neem oil (Suneem) against Anopheles gambiae sl adult emergence

Poster (2012, October 08)

Metarhizium anisopliae have shown great potential for the control of malaria vectors. However, their ability to control aquatic stages of anopheline vectors with conidial formulation is need. In ... [more ▼]

Metarhizium anisopliae have shown great potential for the control of malaria vectors. However, their ability to control aquatic stages of anopheline vectors with conidial formulation is need. In laboratory condition (25°C and 76%RH), we formulated M. anisopliae with emulsifian neem oil (Suneem 1%) before application on An. gambiae larvae at 4, 6, 8, 10 and 12 % (v/v) to determine the LD90. We applied in semi-field environment, the LD90 of the formulation into artificial vats on the Anopheles gambiae sl larvae collected from many breeding sites at dry and rain seasons. In laboratory condition, the LD 50 was 4.4 x 10^6 spores/ml and the LD90 was not obtained 24 after exposure. The probite line equation was Y=1.61 x – 0.55 and R²= 0.9793. The LD 50 was 3.1 x 10^6 and the LD90 was 5.3 X 10^6 spores/ml 48 h after exposure. The probite line equation was then Y= 1.69 x + 1.79 and R²= 0.9757. Microscope magnifying revealed also the fungal attack via cuticle and mycelia germination one dead larvae and pupae. In semi-field environment, treatment revealed that, at 5.3 x 10^6 spores/ml, the formulation has a great emergence inhibition of mosquito adult formation. No significant difference was observed between dry and rain season application of M. anisopliae on the larvae. Therefore, a combination of M. anisopliae with Suneem may provide a more sustainable management strategy for malaria vectors control at the larval stages. [less ▲]