Introduction to the Black Water Fly
Professor Yu Ziniu of Huazhong Agricultural University and Professor Liu Yusheng of Shandong Agricultural University explored the breeding of black water fly, and through several years of research, solved some problems in the production of black water fly, and hoped that a large number of large-scale breeding of black water fly would be promoted.
The prevailing method is to divide the rearing of black water fly into two parallel parts: one part is the rearing of the breeding insects, and the other part is the larval scale rearing. Breeding insect culture is more delicate, requiring the production of insects to be large, can be used to lay eggs to reproduce offspring, to provide an uninterrupted source of insects for production; larval scale breeding part of the production application for the purpose of maximizing the production of larval bodies and pre-pupae production. Large-scale production should not only take into account the largest amount of production, but also the lowest production cost, and can produce a certain amount of social or ecological benefits.
Site selection for black water fly culture
The establishment of black water fly breeding sites should be far away from the living areas of residents, and it is best to choose places with a large amount of livestock manure and household garbage. Such as in the farm, next to the rural vegetable market, winery and other places. Large quantities of cheap feed can be obtained nearby without causing environmental incongruity. Breeding is carried out on farms and villages, and management costs are reduced by increasing the scale. In these places, transportation is convenient, close to the market, and the existing plant resources can be used to quickly enter production.
Egg collection
First of all, it is necessary to set up a lure pot from the outside to collect the egg blocks as a source of insects. Black water fly spawning must choose a gap, generally the width of the gap is not more than 2mm, the depth is not less than 7mm. Here is a common method of egg harvesting.
Choose a shaded and rainproof place outdoors, place a lure pot, place chicken manure, fermented bran and other odorous substances in the pot; place porous egg harvesting plates on the pot. Booth and Sheppard's corrugated cardboard egg collection box method, invented in 1984, is more practical. The egg collection board is made of corrugated cartons, and the cartons are cut into cardboard strips about 30 cm long and 6 cm wide, with the long side being porous edges. Cardboard is stacked in about three layers. After two days, cardboard already with eggs is placed on top of the feed incubator, and the hatched larvae automatically crawl into the feed for feeding. Corrugated cardboard can also be replaced by other blocks with gaps, such as two planks stacked on top of each other, and because the planks naturally bend to form gaps, black water fly can spawn in the wood plank gaps.
Larvae are reared and separated
It takes 2 to 4 days for the eggs of black water flies to hatch, and the hatched larvae automatically crawl into the feed. During the rearing process, black water fly eggs are raised as much as possible with eggs laid in one day. In this way, the larvae grow neatly and are easy to manage in the later stages.
The feed of the early larvae uses bran that has been fermented for more than one day, and the humidity of the feed is preferably based on the water produced by hand (about 70% water content). The bran is loose and breathable, easy for larvae to eat, and the survival rate of larvae is high. After three to four days, the larvae grow to about 0.6 cm, at which point the larvae begin to feed in large quantities. Depending on the density of insects in the pot, box feeding can be carried out. After this period, the larvae can choose to feed with other feeds.
The cultivation of black water fly larvae can be made from fermented bran, soybean meal, corn flour, livestock manure, leftovers, rotten fruits and vegetables, leaves and melon skins. In actual production, it is recommended to use more domestic garbage and livestock manure for breeding, which not only reduces costs, but also reduces environmental pollution. Black water fly larvae can be used for box culture, pond culture, and new type barrel culture. Boxed and pond culture is similar to the traditional house fly and big head gold fly breeding method, barrel culture by the American invention of the black water fly domestic waste disposal bucket (also known as biotransformer) feeding, suitable for rural family applications.
Water fly larvae need to have a certain degree of environmental isolation during the breeding process to reduce the impact of odor on the environment. Therefore, black water fly should choose to be farmed indoors, or build a special workshop. The whole breeding process is best not to affect the surrounding environment, so as not to cause environmental complaints.
Boxed
Boxing is a relatively simple method and is suitable for indoors with less space. Maximizes space utilization and is extremely easy to manage.
(1) Feeding equipment including feed boxes, multi-layer feeding racks, etc. The feed box is 12 cm high and moderate in length and width, which is easy to operate manually.
(2) Feeding management Put the 4-day-old into the box at a reasonable density. The larval chamber should be kept in a relatively dark environment, and the feed thickness should be maintained at 5 to 10 cm. The water content of the feed is maintained at about 70%, which is subject to the water produced by hand. Feed is added according to the feeding conditions of the larvae, and the residues that have been eaten are removed.
When the larvae grow to about ten days later, the size is basically no longer larger, then there is no need to add feed, after the feed is finished, you can manually divide the worms. Move the box to a well-lit place, at which point the insect feed will drill into the lower layer of the feed, shovel out the surface feed with a spatula, and the lower larvae will gather in piles for easy collection. The larval treated slag, composted or dried, encapsulated with plastic tape, can be used as an excellent organic fertilizer.
Pond culture
Pond breeding generally adopts single-layer or double-layer rearing, and requires the construction of large-area factories or simple sheds for production. Pond breeding is relatively extensive, does not require too much manpower input, the use of chicken manure, pig manure for feeding, breeding costs are low, suitable for rural promotion.
Feeding equipment: 2 * 2 m or 2 * 1 m square cement tank, the height of the pool body is about 15 cm. At the corner of the cement pond, a slope of 30 degrees is formed, and the outer side of the slope protrudes outward for the pre-pupae to climb out.
Feeding management: After the larvae are raised to 4 days of age, they are placed in ponds for breeding, and each pond is maintained at about 20,000 heads. The feed in the pond can be filled at once, keeping the feed thickness above 10 cm, or it can be continuously replenished according to the feeding of the larvae. Pond culture generally does not need to remove debris, as long as enough material is added, the larvae can adequately feed.
When the larvae begin to pre-pupate, add water to the feed to make the feed full, at which time the pre-pupa will crawl out in large quantities. Place the bucket under the slope of the pool corner, and after the pre-pupa climbs out, it automatically falls into the bucket. After the worms have finished climbing, use a shovel to shovel out the treated residue, dry it or compost it.
Management of seed larvae, pre-pupae and pupae
Large-scale rearing of black water fly requires a large number of eggs to ensure the continuity and scale of production. Therefore, the cultivation of seed insects, the collection and preservation of pre-pupae and pupae, as well as the mating and egg collection of seed insects are also extremely critical. The number of seed insects is determined according to the actual production scale. Generally, it can ensure about 10,000 adult insects per day, which can reach a daily production of 300 kg.
Breeding larvae can be kept individually, and the basic method is to add sufficient and diverse feed to produce large pre-pupae. Pre-pupae with large individual size and strong mobility can also be selected as breeding insects in large-scale production products.
Pre-pupae are extremely prone to mass death. The climate is dry, or the temperature is too high, and the insect body is prone to water loss and death. If gaps are missing, or if proper pressure is not provided, the pre-pupa will crawl all the time, draining physical strength and failing to pupate. The solution is to lay a thin sand with a thickness of about 15 cm in the adult cage chamber that has been built, of which the bottom 5 cm is wet soil and the upper layer is dry soil. Turn the sand over periodically to the degree of wetness, when the bottom sand dries out. Water is slowly injected in one corner of the sand layer, and after a period of time, the lower layer of sand will become wet. The black water fly is pre-pupated on the sand, and the pre-pupae burrows itself into the sand, no longer active, waiting for the pupa to pupate. Under normal circumstances, black water flies pupate in about a week, and the pupal period does not need to be managed, waiting for feathering.