Feed additives to chick starter mixtures under tropical conditions.

In two short-term experiments (28 and 31 days, respectively), the ergotropic effect was tested of the growth promoters nitrovin (25 mg/kg mixture, and a chinoxalin-1,4-N-dioxide derivate (25 and 50 mg/kg mixture). The experiments were carried out on a total of 1,952 unsorted one-day-old White Leghorn chicks under tropical conditions in Eastern Ethiopia (College of Agriculture at Alemaya). On addition of 50 mg chinoxalin-1,4-N-dioxide, the final weight of the chicks was 105.6 and 104.6%, respectively, in the first and second experiments as compared with the unsupplemented groups. The amount of feed required for each weight gain was reduced to 94.0 and 91.4%, respectively. Nitrovin and smaller amounts of chinoxalin-1,4-N-dioxide increased the body weight to 104.2 and 104.0%, respectively, as compared with the control. The feed requirement (94.6 and 99.9%, respectively) was not reduced significantly (alpha greater than 0.05). Further experiments will be necessary, using other feed additives, more chicks, and longer experimental periods.