Hatching technology of geese

The artificial hatching of geese has gradually changed to electrical hatching, and electric hatching has more advantages than traditional bed hatching, such as constant temperature, clean hygiene, convenient management and so on. The disadvantage is that the investment in equipment is a little larger. The hatching rate of goose eggs can be significantly improved by using electrical incubation at variable temperature. The hatching technology of geese is introduced as follows:

Equipment and hatching procedures

To hatch geese at variable temperature, several incubators are generally used, full-in and full-out system is adopted, and different environments are set up in stages. The whole incubation period can be divided into 3 or 4 stages.

1. If it is divided into three stages, it will be 1-14 days, 15-28 days and 29-31 days respectively. The temperatures were 38 ℃, 37.5 ℃ and 36.5℃, respectively.

2. If it is divided into four stages, they are: 1: 9 days, 10: 18 days, 19: 28 days, 29: 31 days. The temperatures were 38 ℃, 37 ℃, 37 ℃ and 36.5℃, respectively.

The latter is suitable for incubators of a certain scale. In the first three periods, different temperatures and humidity were set in different incubators, and the hatching was carried out in the hatching machine in 29-31 days. This requires two to three incubators and one hatching machine.

Structural characteristics of goose eggs

The relative surface area of goose egg is small, the shell is thick, the shell is hard and not easy to be broken, and the shell film is also thick, the stomata are small, and the inner shell membrane is tough, which leads to the stomatal seal is very strict, which directly affects the gas exchange, water evaporation, heat energy conduction and shell-pecking. Conventional hatching techniques are not easy for goslings to break their shells.

Selection and disinfection of breeding eggs

Breeding eggs should come from healthy geese, and reasonable feed nutrition is also an important factor affecting the quality of breeding eggs. In addition, egg weight, egg shape, eggshell quality, egg freshness, cleanliness, and appropriate male-female ratio are all necessary conditions for the selection of goose eggs. After breeding eggs are produced, they are usually sterilized twice. For the first time, fumigate and disinfect with formalin before storage (30 milliliters of formalin and 15 grams of potassium permanganate for 20 minutes in 1 cubic meter). For the second time, soaking and disinfecting during hatching can also wash off the dirt on the egg surface (can be soaked with 0.1% bromogeramine or 0.03% potassium permanganate for 2 or 3 minutes, wash and drain and hatch).

Preservation and placement of breeding eggs

The suitable temperature for preserving breeding eggs is 10-15 ℃. The suitable time is within one week, no more than 15 days at most, and the hatching rate of breeding eggs more than 15 days decreases obviously. The suitable humidity is about 75%. If the preservation time is more than 1 week, you can turn the eggs once or twice a day and change the angle. If you raise one side of the egg box, the next time you turn the egg, raise the other side. The egg breeding bank should be clean and hygienic, and there should be no direct sunlight.

Control of temperature and humidity

1. Temperature: because goose eggs have special structures such as shell membrane, eggshell, stomata and inner shell membrane, at the initial stage of hatching, the eggs are heated slowly, and their fat content is relatively high. In addition, a large amount of physiological heat is produced in the middle and later stage, which makes it difficult to dissipate heat. Therefore, in the process of hatching, the principle of Shi Wen is: high in the early stage, flat in the middle stage, slightly lower in the later stage, and slightly higher in hatching. It should be noted that the egg temperature is different from the air temperature inside the machine, and they are quite different because of the difference in gestational age, machine wind force and external air temperature. the temperature measured by the electric incubator is generally the air temperature inside the machine, so attention should be paid to monitoring the temperature of embryo eggs. The mastery of temperature varies with model, air temperature and goose egg breeds.

2. Humidity: the principle of temperature is high at both ends and flat in the middle. It is 65% 70% in the first 9 days, 60% in 18 days in the middle stage, 65% in 28 days in the later stage, and 72% in 29 days. In the early stage, the embryo should form a large amount of amniotic fluid and allantoic fluid, and the temperature in the machine is higher, and the relative humidity should be slightly higher. In the middle stage, in order to exclude amniotic fluid and allantoic fluid, the humidity should be slightly lower. In the later stage, in order to prevent villi from adhering to the eggshell, the relative humidity should be increased to the same as that in the previous stage. The humidity in the hatching period should be higher, 72%. 25 days later, it can be combined with water spraying to increase the humidity. Humidity should not be too high, more than 75% can cause poor ventilation, embryos due to poor gas exchange caused by acidosis, resulting in embryo asphyxiation death. On the other hand, the humidity is too high when coming out of the shell, a large number of bacteria multiply in the machine, and the goslings are prone to umbilical infection and omphalitis.

Cold eggs and spray water

Cooling eggs and spraying water are effective measures to adjust humidity and have a great influence on hatchability. In the early stage of hatching, the eggs are generally not cold, and the egg temperature in the middle and later stages is often more than 39 ℃. Because the eggshell surface area is relatively small, the stomata are small, and the heat dissipation is slow. If you do not send out too much physiological heat in time, it will affect the development or cause stillbirth. Cold eggs can enhance the gas exchange of embryos and eliminate the accumulated heat in the eggs. When hatching to 17-19 days, open the lid of the box and cool the eggs once a day. After 25 days, there is more physiological heat, cooling the eggs 3 times a day for 4 times. The time of cooling eggs varies, and they can be mastered flexibly according to the actual situation. When the egg temperature dropped to 35 ℃, continue to hatch, spraying water is the key to improve the hatching rate of goose eggs. There are three functions of water spraying:

1. Destroy the membrane on the shell.

2. Promote the continuous contraction and expansion of eggshell and shell membrane, destroy their integrity, increase their permeability, accelerate water evaporation and normal weight loss of eggs, increase the volume of air chamber and provide sufficient oxygen.

3. Cause the eggshell to be brittle. The outer membrane of the goose egg is thick and the eggshell is hard. The former affects gas exchange and water evaporation, while the latter makes it difficult to peck the shell. The existence of shell membrane is beneficial to the early stage of hatching and disadvantageous to the later stage. To get rid of it, spray water on the eggs after 19 days (early spraying is bad for the closure of allantoic vessels). Spray cold water when the temperature is high and warm water of 35 ℃ when the temperature is low. Spray 1 spray 4 times a day, as appropriate. Spray the eggs wet, dry them and continue to hatch. After repeatedly spraying water, the calcium carbonate in the eggshell becomes calcium bicarbonate under the action of water and carbon dioxide, the hard eggshell becomes soft, and the goslings break easily, thus improving the hatching rate.