This method can help answer key questions in livestock entomology, such as what stable flies require for development. The main advantage to this technique is that it is simple. The medium is composed of only four ingredients.
Propagating Stomoxys calcitrans begins with collecting eggs from a stock of flies. This involves preparing an egging cup. Dip the tip of a cloth into a 250-milliliter jar filled with 40 degrees Celsius water.
Then wrap the cloth around the outside of the jar and secure the cloth with a rubber band. Fold the loose end of the cloth over the top of the jar to limit access to the water. Now place this cup into a cage of eight to 10-day old flies.
After two hours, the gravid females will oviposit enough eggs for the next generation. Typically, 2, 500 flies will produce eight to 40, 000 eggs in two hours. Next, using water, rinse the eggs off the egging cloth into a small, empty dish pan.
Theoretically, eggs can survive in water for eight to 12 hours. However, it is best to limit the time to five hours or less. To rear larvae from the eggs, make up fresh fly medium in a 10-liter plastic dish pan.
Then make a shallow furrow in the medium along the length of the dish pan for the eggs. To transfer the eggs, make a specialized egg pipette. by inserting a mesh screen into a pipette.
Simply cut the pipette at the desired location. And glue a number 100 mesh screen into the pipette at that position. Then, using the egg pipette, collect about one milliliter of eggs and deposit them into the furrow.
This amounts to about 8, 000 eggs. Then cover the eggs with a thin layer of medium so they don't desiccate. Next, cover the dish pan with a standard cotton pillowcase, and secure it with a rubber band.
When the dish pan is kept under standard rearing conditions, larvae will develop in about two weeks. Within nine days, the larvae will have moved to the edge of the medium, and by day 14, they will have pupated. Many pupae can be found at the dish pan's edge under a crust of food.
Regularly scoop the pupae from the dish pan and transfer them to a clean 10-liter dish pan. Add water to break up the clumps of pupae and medium. Most of the food will sink and the pupae will float.
Transfer all the floating materials to a stack of sieves and rinse off the remaining medium. The pupae will collect in the number 12 sieve. Rinse the pupae until they look clean, and then float them in clean water.
Now collect the cleaned floating pupae in a colander. Then transfer the pupae to a drying screen and allow them to dry under a steady air stream from a fan. Some adults will start to eclose in a few hours and some will take a few days.
An alternative method of collecting pupae is to use a pupal shelf, which is made from a plastic section taken from the end of a 10-liter dish pan. To use the shelf, load a 10-liter dish pan with medium tapered from about 2.5 centimeters deep on one end to 7.5 centimeters deep on the other. Then place the shelf in the shallow end and tape the edges to prevent larvae from crawling alongside the shelf.
Next, saturate a sponge with water and wrap it in a water-soaked cloth. Place it on the shelf about 1/2 inch from the medium. Importantly, monitor the sponge daily to make sure it stays moist.
Allow the larvae to pupate on the shelf, keeping the sponge and cloth away from the food, minimizing the need for extensive cleaning. For a colony health metric, collect 100 pupae from each generation. Weigh the pupae and track their emergence and sex ratio.
Before loading pupae into an empty adult cage, line the cage with butcher's paper. Then load 50 grams of dry stable pupae into the cage. Within 24 hours of the first flies eclosing, start feeding them blood.
Soak 20 to 25 milliliters of bovine blood into a feminine napkin and position it on top of the cage. Replace it daily until one day prior to oviposition. After oviposition, freeze the cage for four to eight hours to euthanize the flies.
Then clean the cage by removing the paper, rinsing frass from the sides and floor with hot water, and scrubbing all surfaces with laundry detergent and chlorine bleach. Then rinse the cage with hot water and allow it to dry. Over 3 1/2 years, three different bulking agents and two colonies were maintained.
Cottonwood gave the best yield. The sex ratio was slightly biased towards females. Egg-to-adult survival was approximately 36%Using pine, which was more available than cottonwood, brood number was slightly lower.
But individual size was slightly larger. Thus, pine is an acceptable choice. Overall, the operation is very affordable in terms of material costs.
The current cost for the medium components is one dollar and seventeen cents per dish pan. Sanitary napkins are five cents each, and a gallon of blood can cost up to five dollars. After watching this video, you should have a good understanding of how to raise stable flies from egg to adult.
While attempting this procedure, it's important to remember to be consistent. This makes it much easier to troubleshoot. Following this procedure, other methods like different diets can be performed in order to answer additional questions like what are the nutritional needs of stable flies.
