Different Blood and Sugar Feeding Regimes Affect the Productivity of <I>Anopheles arabiensis</I> Colonies (Diptera: Culicidae)

Abstract

The success of the sterile insect technique for the management of mosquito populations depends on the release of large numbers of competitive sterile male insects. Sustainable mosquito production can only be obtained when proper mass-rearing equipment and adequate methods are available, including those to feed blood to the female mosquitoes. The blood feeding apparatus Hemotek consists of a small aluminum plate to which a collagen membrane is fixed and filled with blood kept warm by an electric heating element. A larger aluminum plate was developed to feed a larger number of female mosquitoes with blood that is kept at a constant temperature. The effect of different blood feeding regimes (feeding frequency and time the blood is kept in the Hemotek) and sugar deprivation before blood feeding on egg production of female Anopheles arabiensis Patton was tested. Egg production was higher when blood was offered to the mosquitoes every day as compared with every 2 or 4 d. Sugar deprivation for 7 h before blood feeding enhanced egg production by 50% compared with female mosquitoes that had continuous access to sugar. Neither male nor female survival was impaired. Finally, we showed that the same blood could be kept warm and used over several hours to feed mosquitoes in multiple cages without any impact on egg production or hatch rate. Being able to use the same blood over extended periods would save considerable time, handling, and funds.

Large-scale Anopheles arabiensis egg quantification methods for mass-rearing operations

“…The Dongola strain of An. arabiensis , originating from Sudan, was maintained at the IPCL (Seibersdorf, Austria) in small rearing cages (30 × 30 × 30 cm BugDorm Model 1, Taiwan) following the rearing procedure described by Damiens et al [ 16 ]. Eggs were collected in black-lined plastic cups containing a wet sponge covered by a filter paper which was collected from the cages and replaced twice a week.…”

“…Male mating ability and female fecundity were assessed with fifty males (either from dried or fresh eggs) and fifty females obtained from fresh eggs placed together in small rearing cages (30 × 30 × 30 cm BugDorm Model 1, Taiwan). Females were offered a blood meal with the Hemotek membrane feeder [ 16 ] for 1 h on the 5th and 6th days. All blood fed females were then kept for 3 days for egged en masse in plastic cups containing a filter paper on wet sponge.…”

The effects of genetic manipulation, dieldrin treatment and irradiation on the mating competitiveness of male Anopheles arabiensis in field cages

“…Adults were kept in standard 30-cm cubic insect cages (Megaview Science Education Services Co Ltd, Taiwan) and continuously supplied with 10% [w/v] sucrose solution with 0.2% methylparaben [20]. Females were blood-fed weekly on thawed, defibrinated bovine blood using a modified Hemotek feeding apparatus (Discovery Workshops, Accrington, UK) [21]. Gravid females were allowed to oviposit in plastic cups with black lining containing a wet sponge over which a filter paper was placed.…”

Does mosquito mass-rearing produce an inferior mosquito?

“…Pupae of the same age and adult males of the same size were used here in order to minimize any effect of adult size and age on the mating competition between males from the SRS and MRS treatments. The observed variability in fecundity across all treatments and the relatively low number of eggs produced by the females could be attributed to female specific factors, such as the success of insemination or the volume of blood meal taken, which are known to affect insect fecundity [ 35 ]. The en masse egg collection method could partly explain the differences observed in the average number of eggs laid per female between treatments because it cannot take into account the exact number of females that laid, thus making estimates very approximate, as noted previously [ 36 ].…”