Growth in the Hubbard broiler: increased size following early handling.

Hubbard cockerels, 1 day of age (n = 91), were divided into 3 handling groups: (1) chicks from the 5-Day group were removed from the brooder and isolated at 22 degrees C for 3 min on each of the first 5 days; (2) chicks from the 15-Day group received this treatment for 15 days; and (3) Control chicks were not handled. Within each group half were fed broiler starter for 5 weeks, and half were fed layer starter which produces slower growth. On Days 28, 35, 42, and 49 the average weight of 5-Day birds was significantly higher than that of Controls; 15-Day birds weighed slightly less than birds in the 5-Day group. The weight advantage of the 5-Day birds occurred with both starter rations, at all weighing periods, and did not appear to reflect increased food consumption. Similarities between these findings and results obtained with rodents were noted.