MOSQUITO COLONY MAINTENANCE PROCEDURES AND EQUIPMENT |
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LARVAL PANS |
Pans are kept in a small room that is maintained at 90 degrees F with air circulated continously by fans so the pans stay at room temperature. All pans have air bubblers in them to prevent surface scum. When larvae have pupated they are "poured up" by emptying the pans through a hose into a screen. Pupae are then placed in small pans of clean water at room temperature and placed in the adult cages to emerge for 4-5 days. The pans are then removed and the cage is blood fed. |
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Adult cages are kept at 80 degrees F and 80% humidity. Cotton soaked in sugar water are kept in the cages at all times. |
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Sugar cottons are made by cutting rolled cotton into squares and then soaking them in a 10% sugar water solution. Cottons are placed in plastic containers and the excess water is run out (do not wring cottons out!) Mid week the cottons are flipped over to expose the clean surface. If the room is at proper temperature and humidity no other maintenance is needed. If the room gets dry the cottons should be rehydrated. Cottons are changed weekly. |
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BLOOD FEEDING |
Live anesthetized chickens give the best egg production but for financial and humane reasons artificial methods of delivering purchased chicken blood are now used. Some species feed on blood soaked cotton but others require a blood filled condom suspended in the cage for adequate feeding levels. |
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EGGING |
Culex quinquefasciatus lays their eggs in "rafts" on fresh water. They prefer water that is fairly foul. This is replicated in the lab by putting oak leaves in a jar and filling it with water and letting it set for at least 4-6 weeks then draining the water into a container for easy access.
The jar can be refilled with new water to set up again. It is important to avoid getting other organic material in the mixture or the water will be too foul for even sewer mosquitos not to mention lab technician's noses. Leaves can last a year or more by adding new leaves to the old. The whole batch should be replaced periodically. Bowls containing the drained oak flavored water are then placed in cages with gravid females and they will lay on the surface. If the cage is full extra bowls should be placed so that the females don't drown each other fighting for laying space.
The rafts can be counted out to be placed in the larval pans above. Generally 25 rafts will be used for the size of pans used at the center. |
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Ochleratatus taenorynchus normally lay their eggs on damp sand or organic debri near shorelines. This is replicated by either pads made of cheesecloth or containers of moss. The egg laying surface is kept damp but not too wet or the eggs will hatch. The egg pads are "poured up" every 2-4 weeks using an ice water bath system and then put on cotton pads in petri dishes for storage. This method is more time consuming but has the advantage of knowing how many larvae can be expected to hatch from each cotton square or a piece of cut cotton square. The moss is simply put in a closed container which is much less time consuming but is hard to estimate possible larval yields. |
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Dried O.t. eggs from moss. Viability of dried eggs varies widely. |
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