General Information:
Drosophila melanogaster or the black-bellied fruit fly, fruit fly, vinegar fly or fruit fly has become indispensable in terraristics. The stubby-winged form has long since replaced the flight-capable wild form. The advantages of the flightless breeding form are obvious. The ease of handling the animals is enormous – in return, they are no longer quite as capable of reproducing as their wild form. Drosophila melanogaster are very small. It has a length of about 2 mm to 4 mm. Depending on the species, they are black, yellow-brown or mottled in all shades of brown and have bright red eyes. Just one day after mating, the females lay their eggs in fermenting and rotting fruit – around 400 in total. After pupation, it takes a maximum of eleven days for the first offspring to hatch. The flies have a life expectancy of 30 to 40 days. Due to the short generation sequence, they are suitable as laboratory animals. It is the most successful laboratory animal in the world. The diptera is now one of the best-studied species in the world and it is impossible to imagine genetics laboratories without it.
Breeding:
Breeding these animals is very easy and, compared to other animals, very inexpensive. For breeding, I use washable glass containers or plastic containers with a capacity of 500–1,000 ml. I fill them with about 3 cm of breeding substrate. For the walking surface, I place wood shavings, egg cartons, crumpled paper, or strips of paper from a shredder on top of the substrate. I usually stock the new breeding boxes with 20–40 flies, which ensures a rapid larval population. I don’t heat the fruit fly breeding area separately; I just keep it at normal room temperature.
| Temperature | Development time |
|---|---|
| +10°C | No development |
| +15°C | 28 days |
| +18°C | 20 days |
| +21°C | 16 days |
| +25°C | 10-11 days |
| +30°C | 8 days |
| +35°C | No development |
Duration of the individual development stages at 25°C
| Ebryonic development | 21 hours |
| 1st larval stage | 22 hours |
| 2nd larval stage | 21 hours |
| 3rd larval stage | 44 hours |
| Doll time | 90 hours |
Therefore, the culture dishes should be kept slightly warmer, and the containers with the already hatched insects should be kept slightly cooler to extend their lifespan. Egg laying is best observed shortly after the cultures are set up, when the larvae are not yet a nuisance. The eggs are typically laid on the surface of the culture medium. The development period depends on temperature.
During larval development, the animals moult twice. The length of the animals increases and reaches 4-5 mm in the third stage. The larvae burrow into the culture medium. To pupate, they usually leave the culture medium and migrate up the wall of the culture vessels.
Small fruit fly “ant”
Perfect for rearing young animals The small fruit fly “Ant” (Drosophila melanogaster) is a flightless breeding form that is ideal as a food animal for a variety of invertebrates, reptiles…
Growth medium:
Drosophila larvae feed on yeast. The culture medium must be formulated to provide favorable growth conditions for yeast. It should be firm enough that nothing spills out when the container is turned upside down. However, the larvae must be able to burrow into the substrate.
Ingredients for a breeding tank in the summer:
- 1 cube of fresh yeast (1 packet of dry yeast)
- 2 teaspoons of sugar
- 40 g rolled oats (3 heaping teaspoons)
Ingredients for a breeding tank in winter:
- 1 cube of fresh yeast (1 packet of dry yeast)
- 1 tablespoon of sugar
- 135 ml vinegar (8 tablespoons)
- 1 bag of mashed potatoes
- Water (half the amount of liquid listed on the package)
There is no need for an antifungal agent such as Nipagin, since the vinegar content is very high. You can also omit the yeast, since yeast cells are present on the legs of the breeding flies. However, this significantly slows down the breeding process. Given the presence of yeast, it should be clear to everyone that completely odorless breeding is not possible. At first, the smell of vinegar predominates. The longer the breeding process continues, the more unpleasant the odor of the substrate becomes.
Mites are the biggest problem in Drosophila breeding. Therefore, when populating new breeding containers, I recommend using as many fruit flies as possible. This increases the number of larvae, and their vigorous movement in the breeding medium helps reduce mite reproduction. In addition, you can place the breeding boxes in a water bath at all times. This prevents, first, the mites from migrating from one container to another, and second, the dead fruit flies from spreading throughout the entire apartment.
Feeding Drosophila:
Of course, you can go to your wife’s or girlfriend’s closet to “borrow” a pair of tights. That’s how many people build bridges from the breeding cup to the insectarium. But I usually end up with some escaping anyway, and pantyhose are way too expensive in the long run—especially if you happen to grab the wrong pair. You can easily avoid the resulting friction with the opposite sex by simply putting the breeding cups in the fridge for a few minutes. Afterward, you can calmly open the container, tap the insects out, and even dust them with a vitamin supplement (Korvimin ZVT). The fruit flies will be in a state of cold torpor for a short time, which doesn’t harm them, their eggs, or their larvae.
