Toxic Effect of Blood Feeding in Male Mosquitoes

Abstract

Blood- and sugar feeding of female mosquitoes has been frequently observed in the laboratory and in the field, but only sugar feeding of males has been reported. Here, we describe for the first time that Culex quinquefasciatus males feed on blood as well. Blood feeding easily happened on a blood-soaked cotton roll and, to a lesser extent, through a thin artificial layer. Mating history of a male specimen does not affect his blood feeding behavior. Male mosquitoes feed on blood even when they have a readily available sugar source. Nevertheless, feeding on blood reduces the survival rate of males to just a few days, as compared to more than a month for mosquitoes fed only on sugar. Comparing survival of male mosquitoes fed on blood only, sugar only, and a combination of both clearly demonstrated that mortality is not affected by malnutrition (reduced sugar levels), but rather due to ingested blood. On average male mosquitoes ingested ca. 0.5 μl of blood, i.e., about 10% of the amount of blood ingested by an engorged female. Although this unexpected observation of blood feeding in the laboratory by male mosquitoes is interesting, structural impairment prevents male feeding on vertebrate blood. In agreement with the literature, male and female proboscises and stylets were in general of similar size, but male mandibles were significantly shorter than female counterparts, thus explaining their inability to pierce through skin layers.

Molecular Detection of Rickettsia felis and Rickettsia bellii in Mosquitoes

“…In each mosquito species found to be infected, similar numbers of males and females were positive for R. felis, overall 1.5% (27/1809) and 1.8% (22/ 1242), respectively. As male mosquitoes do not take blood meals (Nikbakhtzadeh et al 2016), they most likely become infected by vertical transmission. Our data then provide further support for transovarial transmission of R. felis in mosquitoes (Dieme et al 2015) and indicate this occurs across a wide range of mosquito species.…”

DEET as a feeding deterrent

“…The sealed cotton rolls were placed in between the CO 2 dispensing needles and the Dudley tube. Five microliters (the amount of 1 blood meal (Nikbakhtzadeh et al 2016) ) of defibrinated sheep blood were smeared onto the surface of the Parafilm (to prime mosquitoes to start feeding). CO 2 flow was initiated, and the assay was recorded with a camcorder equipped with a Super NightShot Plus infrared system (Sony Digital Handycan, DCR-DVD 910).…”

Activity of a selective insecticide (methoxyfenozide) against two mosquito species (Culex pipiens and Culiseta longiareolata): toxicological, biometrical and biochemical study

“…Three days after emergence, female adults were artificially fed with fresh heparinized sheep blood for 2 h using a Petri dish covered with a stretched layer of parafilm in accordance with the procedure of Nikbakhtzadeh et al . (). Feeding stations were maintained at 37 °C with the aid of a circulating water bath.…”

“…Pyrex storage jars (80 × 100 mm) containing 150 mL of tap water were maintained under an LD 14 : 10 h photocycle at 25 ∘ C. Larvae were fed daily with fresh food consisting of a mixture of biscuit-dried yeast (75 : 25 by weight) and water was replaced every 4 days. Three days after emergence, female adults were artificially fed with fresh heparinized sheep blood for 2 h using a Petri dish covered with a stretched layer of parafilm in accordance with the procedure of Nikbakhtzadeh et al (2016). Feeding stations were maintained at 37 ∘ C with the aid of a circulating water bath.…”