Thermal environment in two broiler barns during the first three weeks of age

Abstract

A B S T R A C TThe objective of this research was to evaluate the internal thermal environment of two broiler barns featuring different ventilation systems representative of Brazilian and South American poultry production industry: (a) a negative-pressure tunnel and (b) a positivepressure lateral ventilation system. Environmental parameters such as dry bulb temperature, relative humidity and temperature-humidity index were assessed; temperature maps for day and night average conditions were determined for the first three weeks of life. Better uniformity of the thermal environment and comfort conditions inside the negative-pressure tunnel were found.Ambiente térmico em dois galpões de frangos de corte nas três primeiras semanas de vida R E S U M O Objetivou-se, nesta pesquisa, avaliar o ambiente térmico interno de dois galpões de frangos de corte com diferentes sistemas de ventilação representativos da indústria de produção de aves de corte brasileira e sul-americana: (a) um com pressão negativa tipo túnel e (b) outro com ventilação lateral e pressão positiva. Parâmetros ambientais do conforto térmico, tais como temperatura de bulbo seco, umidade relativa e índice de temperatura e umidade, foram avaliados; mapas de temperaturas médias para as condições de dia e noite foram determinadas nas três primeiras semanas de vida das aves. Melhor uniformidade ambiental e condições de conforto térmico no interior do galpão com pressão negativa foram observadas.

Thermal environment of masonry-walled poultry house in the initial life stage of broilers

“…Similar results were observed by Hernandez et al (2016a), who mapped curtain-walled poultry houses where the air relative humidity near the heating system was also lower than that observed in the other regions of the facilities, with humidity levels below 40% occurring in the seven first days of bird housing.…”

“…The ∆T observed in this experiment was higher than those reported by Hernandez et al (2016a), who worked with negative-and positive-pressure, curtain-walled poultry houses and obtained mean ∆T values of 4.7 ± 2.9 o C and 4.2 ± 4.1 o C, respectively, in the initial life stage of the birds.…”

“…The higher difference between mean indoor and outdoor shed temperatures observed in this study in comparison with the values reported by Hernandez et al (2016a) demonstrates the greater thermal insulation capacity of poultry sheds fully walled with masonry compared with curtain-walled poultry C.…”

“…This THI distribution trend was expected, given the contribution to heat increment from solar radiation via noninsulated roofing as well as the generation and dissipation of heat by the birds themselves, which contributes to increasing the air temperature and consequently THI values, corroborating Hernandez et al (2016a).…”

“…According to Carvalho et al (2012) and Saraz et al (2012), the distribution of heated air within a facility is influenced by its type, ventilation system, insulation, air temperature and relative humidity, and mainly by the heating system employed. Hernandez et al (2016a) mapped a broiler house with a negative-pressure ventilation system and curtain walls and observed that, in the first three weeks of life, air temperature was within the thermal comfort zone, whereas at night temperatures were slightly lower than during daytime. The authors also detected regions with lower temperatures as being those near the air inlets, similarly to these findings.…”