Distribuição espacial do índice de temperatura do globo e umidade em galpão de frangos na primeira semana de vida aquecido por fornalha industrial

Abstract

The development of chicks under thermoneutral environmental conditions is relevant for the future development of the animal. In the first days of life, the chicks do not have their thermoregulatory system fully developed to adapt to adverse environmental conditions. This way, animals subjected to thermal challenges may not be able to recover until the end of the production cycle. The objective of this paper was to evaluate the variability and spatial magnitude of the Black Globe Humidity Index (ITGU) in a chicken house during the first week of life using geostatistics and to detect the regions inside the house that the chicks were in a situation of thermal discomfort. The experiment was conducted in a commercial broiler house with Cobb line chicks and a heating system consisting of an indirect air heating industrial furnace. It was observed using the semivariograms that there was spatial variability of the BGHI being adjusted by the Spherical Model and by the Residual Maximum Likelihood (MRV) method. Maps were generated based on the data interpolated by kriging and it was observed that from the fourth day of life, the animals were subjected to thermal conditions different from those recommended by the literature. In addition, a study on the zootechnical indexes: body mass (MC) and weight gain (GP) of chicks during the same period showed that, from the fourth day of life, the chicks presented a worst development than that recommended by the literature, which may be an indicative that the environmental conditions inside the chicken house were influencing their productivity.