Avaliação do ambiente térmico em um galpão para recria de aves poedeiras no município de Santa Izabel do Pará.

Abstract

Poultry farming stands out in the production of chicken and eggs, with Brazil being the second largest worldwide producer of chicken, exporting mainly to China and the Middle East. In egg production, the country is the fifth largest producer, with growing domestic consumption, rising from 148 to 241 eggs per inhabitant from 2010 to 2022. In the state of Pará, the 15th national producer of eggs, production is concentrated in Santa Izabel do Pará and Santarém. Animal welfare management is one of the major current concerns and considers environmental factors such as temperature and humidity, where deficient control negatively impacts bird health, leading to disease, high mortality, and reduced productivity. Ambience is also a factor that is linked to welfare, as it is a set of external conditions and influences that act directly or indirectly on the animals, considering light, radiation, heat, noise, and the surrounding atmosphere. The thermal comfort zone varies according to the species and the thermal discomfort affects the production and health of the birds, with the ideal temperature being between 18ºC to 26ºC, and the adequate humidity between 50% and 70%. The Temperature and Humidity Index (THI) is used to assess heat stress, with THI ≤ 72 indicating comfort for the birds. Aiming at the importance of welfare in laying hen production, this work aimed to evaluate the thermal conditions in a laying hen rearing shed in Santa Izabel do Pará, seeking to verify the thermal comfort index. The experiment was conducted out in February of 2023 in a shed/aviary in the municipality of Santa Izabel do Pará, with a humid tropical climate, an altitude of 24 meters an average annual temperature of 26ºC, an average relative humidity of 85%, and an average rainfall of 2,870 mm. To monitor the thermal environment inside the evaluated shed, 10 digital sensors, model DHT 11, were proportionally distributed; and for the external environment, the Datalogger 3030.60 sensor was used. Sensor data were transformed into temperature maps using SigmaPlot software version 14.5, and comparison graphs of external and internal areas were made in Microsoft Excel. Temperatures above the recommended for the sheds were verified in the morning and afternoon, with averages of 27ºC to 28ºC, and averages of 25ºC to 28ºC at night. As for the percentages of relative humidity, the morning and afternoon had values above 80%, and the night period from 86% to 100%. The THI obtained numbers higher than recommended in most of the warehouse, being between 72 and 80 in the morning and afternoon periods, and 72 to 78 in the evening period. Therefore, there is a need for solutions for the thermal control of the environment to minimize the impact on the performance of the birds.