Key Technical Points for Natural Mating Breeding of White-Feathered Broiler Chickens

(1) Male-to-female ratio   

The male-to-female ratio refers to the number of hens each rooster is responsible for mating. Taking free-range floor rearing as an example, the male-to-female ratio for fast-growing white-feathered broilers is 1:8-10, for high-quality white-feathered broilers it is 1:9-12, and for layer-type chickens it is 1:10-13. If raised on wire-floor flat rearing, the lower limit should be adopted; before 40 weeks of age the upper limit can be adopted, and after 40 weeks of age the lower limit can be adopted. A rooster can mate with hens up to 20-30 times per day, of which the mating frequency from 3-7 pm accounts for 73.7% of the whole day's mating frequency, and is most concentrated from 5-7 pm, accounting for 47.4% of the whole day. In the 2 hours before sunset, the sexual activity of both roosters and hens is very strong, and some hens even actively solicit roosters to mate. This phenomenon of natural mating in roosters is consistent with the optimal time for artificial insemination, which is after 3 pm.

(2) Mixing arrangements     

When the flock approaches sexual maturity, white-feathered broilers need to be transferred from the growing chicken house to the adult chicken house. When transferring the flock, consideration should be given to transferring the roosters 4-5 days earlier than the hens. After 20 weeks of age, selected breeding roosters are placed into the hen flock at 8%-10% of the number of hens for mixed rearing, so that the roosters become familiar with the chicken house environment. From 20-30 weeks of age, the rearing staff should pay attention to observing whether the roosters exhibit sexual behavior. If the roosters are in poor body condition, have weak libido, or poor semen quality, each breeding rooster should be given an additional 1.5-2 grams of feed per day or milk powder added, to promote their sexual maturity. Breeding roosters reach sexual maturity at 28-30 weeks of age, and have the strongest libido at 30-36 weeks of age, with strong mating ability, high mating frequency, and high fertilization rate. After 48 weeks of age, the libido of roosters begins to decline. To ensure a relatively high fertilization rate, the male-to-female ratio must be appropriately reduced, so that the mating burden on each rooster is lightened. In addition, the mating ability of breeding roosters is related to season and climate. In spring and autumn, the climate is suitable. Breeding roosters are energetic, and the male-to-female ratio can be appropriately larger; in summer and winter, excessively high or low temperatures can also affect the mating ability of breeding roosters, and at this time consideration should be given to increasing the number of breeding roosters, making the male-to-female ratio slightly smaller.

During production, there are usually 25%-30% of roosters whose mating ability declines and whose semen quality decreases, including roosters that are overweight, underweight, have leg problems, or obviously do not mate. Therefore, the male-to-female ratio should be adjusted in a timely manner according to the health status of the breeding roosters, and weak, diseased, disabled, and breeding-valueless roosters should be culled. When the number of roosters is below the requirement and the optimal fertilization rate cannot be obtained, new roosters must be replaced and supplemented. For replacement roosters, it is best to use reserved backup roosters; roosters transferred from another flock will increase the risk of disease transmission and cause stress responses. When replacing roosters, the impact on the pecking order of the flock should be minimized as much as possible. Generally, in the evening, the roosters planned for culling are taken out, and the replacement roosters are immediately put into the flock. To prevent pecking fights, roosters in the same flock should be replaced or removed together, and must not be mixed in with one another. The hatchability of the flock after replacing roosters will not be higher than the highest record of the original flock, and this phenomenon emphasizes the importance of ensuring that sexually mature roosters are in good condition at the start of laying.