How to timely and rationally divide and adjust groups of broiler breeder chickens

Generally at 2 weeks of age, or when flock uniformity is too poor, divide the flock into at least 3 groups - large, medium and small (or over-standard, up-to-standard and under-standard) according to standard body weight, and pick out the sick and weak chickens. Raise the 3 groups scientifically and separately, and regulate body weight by adjusting the amount of feed given. For the large and small groups, it is best to weigh the chickens once every 3 days, put the chickens that reach the standard body weight into the medium group, and put the over-standard and under-standard chickens from the medium group into the large and small groups respectively, so that the number of chickens in the medium group grows larger and larger, thereby improving uniformity. Note that the flock should not be too large during the rearing period; in particular, no regrouping work may be carried out after 18 weeks of age, as the reproductive system is then entering a critical stage of development.