Bodyweight, uniformity and breeder productivity

摘要

One of the most important factors influencing broiler breeder performance is the flock average body weight age and uniformity during the rearing period (Age 14-23 weeks). Optimum breeder performance results following a successful growing management. By controlling body weight all through the rearing period broiler breeders reach sexual maturity with good body fleshing but not with excessive fat deposition. Broiler parents, like their commercial offspring have the genetic potential for fast growth rate. With restricted feeding and controlled lighting programme they are grown to have a low but optimum body weight at sexual maturity so as to improve egg production. Given free access to full feeding broiler breeder females heavier and obese because of their genetic characteristics to over eat. The effects of excessive body weight is higher incidence of chromosomal abberations, reproductive disorders and reduced mating ability which ultimately lower fertility and hatchability. However pullets slightly heavier (100-150 gms) than the standard are found to be better producers as they progress through peak since they could balance energy requirement more efficiently. Problems often associated with under weight birds at sexual maturity are the loss of characteristics peak production and higher numbers of small eggs.