Cluster Index for Accessing Thermal Comfort for Broiler Breeders

Abstract

The aim of this study was to evaluate the thermal comfort of broiler breeders reared in a climatic chamber under known and controlled environments, from the analysis of the clustering behavior of the group, using analysis techniques standard RGB images in video footage. Three thermal environments (26.3, 29.5 and 33.0) were applied for three days each to 12 of Cobb broiler breeders at 26 weeks of age. The ammonia concentration in the air was monitored daily. The clustering behavior was monitored by an RGB camera installed on the roof of the climatic chamber. For each day of the experiment, we selected a sample video for the morning and one for the afternoon, both of 15 minutes, totaling 18 films. The images (frames) were processed to highlight areas of interest (chicken) and then were extracted values of the area and perimeter of the forms assumed by groups of birds. From these values, the rate of agglomeration was calculated using the ratio area / perimeter. This clustering index was calculated for each frame of the 18 selected films. It was found in the statistical analysis that the rate of agglomeration was influenced by air temperature and the ammonia concentration, and the rate decreased when either the ambient temperature or the concentration of ammonia increased. The result validated the clustering index as a potential indicator of thermal well-being of birds, and led to the development of software that monitors this frame by frame rate, allowing an electronic monitoring of the rearing environment.