How to hatch chicks with biogas? Hatching methods and key technical points

Biogas hatching has the advantages of simple operation, safety and reliability, a high hatching rate and lower costs. Because household biogas digesters have a small capacity, this technique is extremely suitable for small-scale farmers (within 1000 birds). The relevant technical parameters are listed below for reference: 1 cubic meter of biogas can hatch 475 eggs, a biogas incubator consumes 30-40 liters of gas per hour, the hatching rate of fertilized eggs is above 90%, biogas hatching raises the hatching rate by 5%-15% compared with electric or oil hatching, and there is no worry about power outages; every 100 eggs hatched saves 3 kilograms of fuel oil.

I. Preparation before hatching

1. Build the hatching room well

The hatching room should be well ventilated, face the sun, be kept warm, be moderately wide, be easy to work in, be cleaned thoroughly and be disinfected with quicklime. An existing room in the house can also be used as the hatching room. During the hatching period the room temperature should be raised to 20-24°C.

2. Make the incubator

The incubator is made of wooden boards or fiberboard, with internal dimensions of length x width x height of 60 cm x 60 cm x 110 cm; it is best made with a double layer, and the space between the layers is filled with insulation material such as sawdust. The cabinet door must be flat, sealed, open and close smoothly, and have the same insulation measures as the cabinet body. The cabinet body can also be made single-layered and wrapped on the outside with insulation material such as old cotton wadding. Inside the cabinet, divide it into sections every 18 cm and make 6 layers of egg trays; the egg trays are made of wooden boards with iron mesh nailed to the bottom, or they can be threaded together with iron wire, with mesh holes small enough not to let eggs fall through; punch one small hole each in the upper, middle and lower parts of the cabinet body, and insert 3 thermohygrometers.

3. Hatching stove

Build the biogas stove top well; the stove top should be flat and smooth, sturdy and safe, and be equipped with an iron pot 57 cm in diameter, with a biogas burner placed under the pot; the biogas delivery pipe should be standardized and reasonable, and the switch should work smoothly and be airtight.

II. Management during the hatching period

1. Treatment of breeding eggs

Select fresh, clean eggs with a smooth shell surface, uniform size and an oval shape, wash them with clean water, and soak them in a 0.1% potassium permanganate solution at 35-40°C for disinfection for 10 minutes.

2. Loading into trays

Drain the disinfected breeding eggs, load them into trays with the large end facing up and placed at a slant, one layer per tray, and move them into a hatching room at 20-24°C half a day early for prewarming, then load them into the incubator, taking care not to put eggs in the bottom tray.

3. Heating

Light the biogas burner; the stove fire heats the pot, the pot temperature rises, and the incubator temperature increases. After heating begins, the incubator should be monitored and managed 24 hours a day, and the cabinet temperature should be controlled according to the following times: early stage (1-10 days) 38.5-39.5°C; middle stage (11-16 days) 38-38.5°C; late stage (17-21 days) 37-38°C.

4. Adjusting trays and turning eggs

When first placed in the incubator, the cabinet temperature is high at the bottom and low at the top, so the eggs should be turned once every 4-6 hours; the method is to swap the trays from top to bottom and swap the position of the breeding eggs in each tray from front to back. In short, by adjusting the trays, the breeding eggs receive consistent temperature, hatch consistently and break the shell consistently.

5. Controlling humidity

Air humidity has a great influence on embryo development. If the humidity is too high, it will block the evaporation of water from the eggs and affect embryo development, and after the chicks hatch their abdomens will be swollen; if the humidity is too low, the water in the eggs evaporates outward too quickly and the embryos develop too quickly, and after the chicks hatch their bodies will be thin and weak; chicks in both of these situations are not easy to keep alive. Generally, the humidity during the hatching period should be controlled at: about 60% in the early stage, about 55% in the middle stage, and about 70% in the late stage. If the humidity is insufficient, add water trays at the bottom of the cabinet to ensure temperature and humidity, so as to ensure uniform shell breaking and easy shell removal.

6. Egg candling

Egg candling is one part of management during the hatching period. Its purpose is to determine whether the breeding eggs are fertilized, whether embryo development is normal and whether the temperature is appropriate, so as to find existing problems and ways to improve them. During the hatching period, eggs are generally candled 3 times. The first time (5-6 days), the eye spot can be clearly seen; if it is absent, this indicates something is abnormal, and the egg can be picked out; the second time (10-11 days), blood vessels can be seen distributed throughout the egg; the third time (17 days), at this point the egg body except for the air cell is completely black, which is called "closing the door"; if the "door" closes early, the temperature is too high and should be lowered, and vice versa.

III. Points for attention

From igniting the fire and raising the temperature until the thirteenth day, the biogas burner must burn continuously without interruption; if there is insufficient biogas, other energy sources must be used as a supplement.

After the chicks hatch, they should be raised for 3 days at a constant temperature of 32°C to improve the chicks' stress resistance and raise the survival rate.