Spatial variability of the environmental characteristics and weight of broilers in shed negative ventilation

Abstract

The objective was to study the spatial variability of environmental characteristics and weight of broilers reared in shed negative ventilation. The work was conducted in municipality of industrial shed Aguiarnópolis, Tocantins state, with mixed batch of 30,000 broiler strain Coob with 42 days in critical hours of high temperature (12h to 15h), composed of negative and misting ventilation system. The gathering of the variables analyzed were performed on 1 day at regular grid totaling 124 points, evenly distributed throughout the house, with 4 m spacing between each point on 31 lines arranged. The environmental variables were collected: air temperature, relative humidity, wind speed besides the temperature of bed. For the verification of weight variability of birds, animals were captured randomly at each collection point, a male bird first, then a female. The variables studied showed moderate to strong spatial dependence. Through the maps of spatial variability can be observed that the imbalance of environmental characteristics cause equal effect on body weight of animals, thereby defining specific areas that affect the performance of broiler chickens, where the variables: relative humidity, temperature environment, bed temperature, wind speed and humidity are above recommended for thermal comfort. Environmental variables like ambient temperature, bed temperature, relative humidity and wind speed directly influence the variability of animal weight.