Effects of broiler breeder management on pullet body weight and carcass uniformity

Abstract

An experiment was conducted to study the effect of broiler breeder feeding management practices on pullet performance, BW uniformity, and carcass traits during rearing (to 22 wk of age). At 3 wk of age, 1,200 Ross 308 breeder pullets were assigned to one of 5 treatments: 1) control: standard mash diet, fed daily; 2) high fiber: mash diet containing 25% lower nutrient density, fed daily; 3) scatter: standard diet in pellet form scattered on litter, fed daily; 4) skip-a-day: standard mash diet, fed on alternate days; or 5) grading: standard mash diet, fed daily (birds sorted into low, average, and high BW groups every 4 wk). Birds on the high fiber treatment consumed more feed (P < 0.0001) and had the highest feed conversion ratio (FCR; P < 0.004) but the lowest ME to gain and CP to gain ratios (P ≤ 0.002). Skip-a-day treatment pullets consumed more ME and CP than birds in any other treatment (P < 0.001). Grading yielded the highest BW uniformity at 22 wk of age (CV = 6.2%), while control and high fiber treatment groups were least uniform (CV > 15%; P < 0.0001). Skip-a-day feed restriction produced birds with the significantly lowest breast muscle and highest liver weight compared to all other treatments (P < 0.05). Variation in shank length, chest width, and breast muscle was lowest in the grading treatment, whereas the CV for fat pad and liver was lowest in the skip-a-day treatment. In this trial, broiler breeder target BW profiles were achieved using combinations of quantitative and qualitative feed restriction, or preemptive management practices. Qualitative diet dilution and skip-a-day management did little to increase flock uniformity relative to the control during the most intense period of feed restriction (7 to 19 wk). Scatter feeding increased flock uniformity to a small degree, whereas grading yielded the highest increase in BW and carcass trait uniformity.