Detailed Explanation of Breeding Rooster Rearing Management and Artificial Insemination Technical Procedures

Breeding Rooster Rearing Management and Insemination

    Artificial insemination technology for chickens has already been widely promoted in many large-scale breeding enterprises. In particular, artificial insemination of breeding chickens is a careful, meticulous and highly technical task, including the selection of breeding roosters, semen quality inspection, artificial semen collection techniques, insemination techniques and other aspects of operational technology that must be accurately mastered.

    This article summarizes a set of artificial insemination technical operating procedures based on the breeding process of the company's new varieties "Jinghong No. 1" and "Jingfen No. 1", and by refining the key technologies in the production links. These procedures have played a key guaranteeing role in improving the fertilization rate of breeding chickens.

    I. Rearing Management of Breeding Roosters

    1. Standards for Selecting Breeding Roosters

    ①. Appearance

    Strong physique, firm muscles, broad chest, bright and spirited eyes, agile and nimble, with a clear crow; thick and sturdy legs and feet, with firm and elastic foot pads; full and glossy feathers with no mixed colors, obvious secondary sexual characteristics, well-developed comb and wattles, with bright red color being preferred.

    ②. Production Performance

    The semen collection volume is generally 0.4-1 mL, and the semen is viscous and milky white. If conditions permit, an electron microscope can be used to monitor sperm density and motility for further screening. The normal density for chickens is generally 2.5-4 billion/mL, with sperm moving in a straight line and no abnormalities.

    ③. Key Points for Breeding Rooster Selection

    First time: 1 day of age, appropriately cull weak and small roosters according to the male-to-female ratio required for the laying period.

    Second time: around 40 days of age, retain roosters with good development and bright red combs.

    Third time: 17-19 weeks of age, retain roosters with good secondary sexual characteristics, strong physique and sexual reflexes.

    Fourth time: around 22 weeks of age, cull roosters with no semen or poor semen quality during semen collection training.

    2. Training Methods for Breeding Roosters

    ①. Training Time

    Between 145-154 days of age, once every two days, generally training continuously four times until insemination.

    ②. Training Methods

    The person holding the chicken should catch it gently and quickly, grasp the base of both legs of the rooster with the left hand and press slightly downward, taking care not to use excessive force, keeping the rooster's body parallel to the holder's left arm and keeping it as natural as possible; the semen collector uses the back massage method, gently stroking from the base of the wings to the tail 2-3 times quickly, then gently pinching both sides of the cloaca, with the index finger and thumb gently vibrating in massage.

    II. Key Techniques of Artificial Semen Collection for Breeding Roosters

    1. Preparatory Work Before Semen Collection

    Before semen collection, the instruments needed for the process should be fumigated and disinfected; the semen collection tube should be pre-warmed (winter: 36-37°C, summer: 35-36°C). Roosters used for semen collection should be fasted for 3-4 hours before collection.

    2. Precautions During Semen Collection

    ①. Movements during semen collection should be gentle to avoid sperm damage caused by human factors.

    ②. During semen collection, personnel are required to cooperate skillfully to prevent waiting for each other, which would prolong the collection time or reduce the collection volume.

    ③. If blood is found mixed in or the semen is thin during collection, the rooster should be singled out and temporarily suspended from use; if feces, feather debris or other contaminants are accidentally collected, the semen should be discarded.

    During the mixing process, never use excessive force,

    3. Semen Quality Assessment

    Semen quality, including semen density and motility, should be periodically tested by electron microscopy, and roosters with poor semen quality should be culled in time to avoid affecting the artificial insemination of breeding chickens.

    III. Key Points for Everting the Cloaca During Artificial Insemination

    1. Mastering the Key Points of Everting the Cloaca

    The person everting the cloaca should operate gently, gently, accurately, steadily and quickly, and must not be rough, to prevent squeezing and breaking eggs in the oviduct, which would cause oviductitis or peritonitis. When applying pressure to the hen's abdomen during eversion, the force must be applied to the left side of the abdomen, and it is best when the oviduct opening just protrudes from the cloaca.

    2. Preventing Human-Induced Infection

    To avoid human-induced infection during the eversion process leading to oviduct inflammation, wipe and disinfect the hands used for eversion with a towel soaked in disinfectant before each eversion.

    IV. Key Points of Artificial Insemination

    1. Preventing Cross-Infection

    During insemination, insist on using one dropper tip per chicken to reduce cross-infection of diseases between chickens.

    2. Key Points of Insemination Technique

    The inseminator gently inserts the insemination tube vertically along the center of the oviduct opening, preventing it from hitting the side wall of the oviduct and causing oviduct damage. The force must not be too great. The insemination depth is generally 2.5-3.0 cm for "Jinghong No. 1" and 1.5-2.0 cm for "Jingfen No. 1"; the insemination volume is 0.025 mL for "Jinghong No. 1" and 0.02-0.025 mL for "Jingfen No. 1". When withdrawing the insemination tube, the dropper tip must not carry semen; if there is semen, insemination must be repeated once. The temperature difference of the thermos cup before and after insemination must not exceed 1-2°C.

    3. Precautions

    ①. During insemination, the insemination tube must not contain air bubbles or air columns, and even less feather debris, feces, blood or other impurities.

    ②. From semen collection to the complete use of the semen, that is, the insemination time, in principle must not exceed 30 minutes.

    ③. Minimize the time the oviduct is exposed to the outside environment, and at the same time avoid the semen waiting for the person everting the cloaca after being drawn up.

    ④. The person catching the chickens should handle them as gently as possible to minimize the stress on the chickens.

    ⑤. When drawing up semen, it should be drawn as much as possible from the horizontal surface of the semen, avoiding inserting the dropper deep into the semen.

    ⑥. After insemination is completed, the person catching the chickens must check whether semen has been brought out; if it has flowed out, re-inseminate, and at the same time avoid pushing the chicken's abdomen, to prevent abdominal pressure causing semen to flow out.

    To Improve the Fertilization Rate of Chicken Artificial Insemination, Seven Passes Must Be Well Controlled

    First is to control the breeding chicken rearing pass well.Breeding chickens for artificial insemination are all kept in cages. Because the range of activity in the cage is small, it is very easy to cause fat deposition, so the feeding amount must be strictly restricted according to the weight gain of the chickens to prevent the formation of fatty liver and the occurrence of prolapse of the cloaca, otherwise it is not conducive to semen collection from roosters and eversion of the cloaca for insemination of hens.

    Second is to control the selection and training pass of breeding roosters well.Breeding roosters used for artificial insemination, in addition to conforming to breed characteristics, production performance and good health, should also be selected for soft abdomen, tail turning upward when both wings are lifted, cloaca everting during massage, large, loose and moist cloaca, large and erect copulatory organ, and good semen output quality. Two weeks before insemination, the roosters to be used should undergo semen collection training so that they form a good conditioned reflex to the processes of restraint, massage and ejaculation, and this can also be used to understand each rooster's sexual reflex habits. Training generally requires about 7 times.

    Third is to control the disinfection pass well.All utensils that come into contact with artificial insemination must be strictly and thoroughly cleaned and disinfected before use. The most convenient and effective disinfection method for breeding chicken farmers is boiling, and the water used must be distilled water. After disinfection, the moisture should be dried off. Utensils that cannot be disinfected by boiling and the hands of operators can be disinfected with alcohol. Operate only after the alcohol has fully evaporated.

    Fourth is to control the semen collection pass well.Semen collection should be carried out 3-5 hours after water and feed have been withheld. During semen collection, the appropriate number of massages and the amount of force should be controlled according to each rooster's sexual reflex habits. If the massage time is too long or the force is too great, the rooster will develop reverse stimulation and fail to produce a sexual reflex, or contaminate the semen by excreting feces and urine or damaging the mucosa; if the force is too small, the copulatory organ will not evert sufficiently and will easily retract. During semen collection, neither the fingers nor the semen collection cup may touch the copulatory organ. It is advisable to use one semen collection cup per rooster, and after collection the semen should be combined with a dropper, to prevent unclean semen from affecting the quality of the whole cup; semen contaminated by feces etc. should be discarded. In winter, the semen collection cup should be pre-warmed to 35°C-40°C.

    Fifth is to control the semen quality pass well.High-quality semen is a milky white, thick liquid. When breeding chickens are sick or feces and urine are mixed into the semen, the semen often has an abnormal color and is thin, and such semen is not suitable for insemination. Sperm motility and density should be examined under a microscope.

    Sixth is to control the semen dilution pass well.Dilution should be carried out immediately after semen collection. When preparing the diluent, the utensils should be clean, the weighing accurate, the drugs pure, and the dissolution complete. Before dilution, the dilution factor should be accurately calculated, and the diluent should be pre-warmed to 35°C-40°C. During dilution, slowly add it along the wall of the semen collection cup into the semen, and finally mix well with a dropper.

    Seventh is to control the insemination pass well.During insemination, the movement of inserting the suction nozzle should be gentle, not forced, to prevent injury to the vagina. The suction nozzle should be inserted 2.5-3 cm deep into the vagina. After the semen is pressed out, do not immediately release the pressure button, to avoid drawing the semen back; the suction nozzle should be withdrawn close to the upper wall of the vagina, to avoid causing semen to flow out. The insemination volume must ensure 10 million effective sperm per day, usually requiring 50 microliters of raw semen with good appearance quality. Insemination should be carried out 3 hours after laying. Under normal circumstances, a production flock can generally be scheduled with an insemination cycle of 6-7 days.