Effects of outdoor access age on performance characteristics of broilers raised in a free-range system

The aim of this study is to determine the effect of outdoor area access age on the performance characteristics of broilers reared in a free-range system. The study used the foreign genotype Ross-308 broiler chickens. Three groups were formed in the study, each consisting of four replicates. The broilers were allowed to access the outdoor area on the 10th day (G10), 15th day (G15), and 25th day (G25) of growth. The stocking density was arranged as 10 chickens/m² indoors and 2.5 m²/chicken in the outdoor area. A total of 180 broilers were used in the study, with 15 chickens in each replicate and 60 in each group. Feed and water were provided adlibitium. From days 1 to 10, the chicks were fed starter feed, from days 11 to 25 they received grower feed, and from days 26 to 42 they were given finisher feed. The live weights of the animals were measured at the beginning of the trial, on the 10th, 25th, and 42nd days of growth. The remaining feed was weighed on the 10th, 25th, and 42nd days of growth. Deaths were recorded as they occurred during the trial. Performance characteristics such as body weight, body weight gain, feed consumption, feed conversion ratio, and livability were determined. At the end of the trial, the body weight of the G10 group was found to be 2580 g, the G15 group 2607 g, and the G25 group 2688 g, with no statistically significant differences between the groups (P>0.05). Between days 1 and 42 of the trial, the weight gain of the G10 group was 2536 g, the G15 group 2564 g, and the G25 group 2645 g, with the differences between the groups also found to be statistically insignificant (P>0.05). During the same period, the feed consumption of the G10 group (4081 g) was found to be higher than that of the G15 group (3804 g) and the G25 group (3853 g) (P<0.05). On the other hand, the difference between the feed consumption of the G15 group (3804 g) and the G25 group (3853 g) was statistically insignificant (P>0.05). Between days 1 and 42, the feed conversion ratio of the G10 group (1.61) was found to be worse than that of the G15 group (1.48) and the G25 group (1.45) (P<0.05). However, the difference between the feed conversion ratio of the G15 group (1.48) and the G25 group (1.45) was statistically insignificant (P>0.05). During the trial, mortality rates were recorded as 96.66% in the G10 group, 100% in the G15 group, and 100% in the G25 group, with differences between the groups being statistically insignificant (P>0.05). According to the results of the study, the earliest age for broilers raised in a free-range system to access the outdoor area was determined to be the 15th day.