The aim of this study was to determine the effects of breeder age and stocking density on performance, carcass characteristics and some stress parameters (H-L ratio, serum glucose, cholesterol and triglyceride levels, tonic immobility test (TI), antibody production, relative asymmetry (RA) and external appearances). This experiment was carried out with 705 one-day old male broiler chicks (Ross ...

A total of 1 200 broiler breeder eggs were collected from a commercial flock at the hen age of 37 weeks and divided into storage treatments of 5 and 15 days. Prior to storage, the eggs were further divided into pre-storage incubation (PRESI) 0 (control), 4 and 8 h treatments. Eggs in the 4 and 8 h PRESI treatment were incubated at a standard dry-bulb temperature of 38.0°C. All eggs were weighed...

The modern commercial broiler is the product of intensive genetic selection for rapid and efficient growth. An unintended consequence of this selective breeding has been the loss of the ability for self-regulation of feed intake to closely match the requirements for maintenance, growth, and reproduction. Thus, the broiler tends to overconsume feed, resulting in a range of metabolic and health p...

Broiler hatching eggs from two young (30 and 31 wk) or two old (52 and 53 wk) breeder flocks were stored for 3, 7, or 14 d at 18 C and 75% RH while being turned 0, 4, or 24 times per day in two experiments. Apparent fertility and hatchability of total eggs differed with flock age in both experiments, but the effect was greater in Experiment 1. Hatchability of total and fertile eggs were decreas...