Effect of Floor Space on Broiler Production in Open House

Abstract

Two collaborative experiments with 12, 960 typical broiler purpose in total were carried out to establish appropriate population density to floor space in open house at Aichi Prefectural Agricultural Research Center, Gifu Prefectural Poultry Breeding Station and Osaka Agriculture Research Center in four seasons 1968 to 1969 and in summer and winter 1969 to 1970. In experiment 1, male and female chicks were grouped into 30, 40 and 50 birds per 3.3m2 and in experiment 2, 40, 50 and 60 birds per 3.3m2, respectively, and body weight gain and economic aspects were investigated.Experiment 1; Avarage body weight gain to 10 week-old in the range of 30 to 50 birds per 3.3m2 was linearly decreased as population density increased, and the rate of decrease corresponded to 3.4g per bird. The crude profit per 3.3m2 which was increased with the increase of population density was 53.4 yen per bird of increasing rate. Feed intake was decreased with the increase of population density, and the difference was significant at 1% level.Experiment 2; Average body weight gain to 10 week-old in the range of 40 to 60 birds per 3.3m2 was linearly decreased as population density increased. Its tendency was more responsive to population density in male chicks than in female chicks. Increasing a bird per 3.3m2 resulted in 3.1g of decrease in body weight gain and in 38.7 yen of increase in the crude profit per 3.3m2. However the crude profit per 3.3m2 in male chicks was lower in lot of 60 birds than in lot of 50 birds. Feed intake was decreased with the increase of population density, and the difference was significant at 5% level.From two experimental results mentioned above, it was suggested that the most crude profit per 3.3m2 was obtained, when the population density was 60 birds per 3.3m2 in female and 50 birds per 3.3m2 in male, although body weight gain and feed intake was decreased as population density increased.