I have some interesting news about my findings from my recent test involving a hydei culture made with milk solids as an ingredient. While it is rather easy to come up with powdered milk, the majority is of a powdered skim variety wheras my experiment was conducted using powdered whole milk. 7 fruit fly cultures were established using potato flakes as the main ingredient during a period of about two weeks. Five of cultures were created first using water and fruit juice as the wetting agent. All cultures were loaded with a warm water / yeast solution and allowed to incubate for several hours before the addition of fruit flies. The last two of the five were made using one tablespoon of powdered milk to one cup of warm water and 1/8 teaspoon of bakers yeast. The solution was allowed to sit for 30 minutes before being split between the two cultures. Beforehand, however the potato medium was made not by mixing potato flakes with warm water, but rather by adding the dry flakes to the container and then slowly adding warm water until the entire meduim had become moist. Then, once the solution was absorbed by the potato meduim, a thin layer of dry potato flakes was added to the surface of the medium to promote a dry surface for the flies to lay in. I would like to point out again that the milk cultures were the last to be made, and they are also the first to hatch. The cultures were all made from the same flies, and have been kept in identical conditions, consisting of high humidity and a steady 85F within a small disconnected refrigerator.Fresh air is constantly pumped into the minifridge via an aquarium air pump, and a single 15 watt light bulb provides all the heat. All of the cultures have large numbers of parent flies, and all are surviving within the cultures with very low mortality rates. Nevertheless, the milk cultures have exploded with maggots, and have already begun to pupate, whereas the five cultures made with either plain water and yeast solutions or water/fruit juice/yeast solutions have yet to even show signs of maggots.
Not only is this data tremendously promising in the search for a decent smelling housefly culture (They kinda smell like sourdough bread now) but the production rate for D. Hydei is phenominal in the milk cultures. I think I just found my new standby recipe for fruit fly medium. I would greatly appreciate it if some of you other breeders who make your own culture medium would follow these directions with a culture of your own to see if the same results can be reached under the conditions that you typivally keep your cultures in. I'd like to know that this isnt just a fluke.
