Analysis of environmental conditions in two different Compost Bedded Pack Barn systems for dairy cattle
¹Federal University of Goiás, Department of Biosystems Engineering, College of Agronomy, BR74690-900, Goiânia, Brazil
²Federal University of Viçosa, Engineering Department, BR36570-000 Viçosa,
Minas Gerais, Brazil
³Federal University of Lavras, Engineering Department, BR37200-000 Lavras, Minas Gerais, Brazil
⁴University of Florence, Department of Agriculture, Food, Environment and Forestry, Via San Bonaventura 13, IT50145 Firenze, Italy
*Correspondence: matteo.barbari@unifi.it, rafaella.andrade@ufg.br
Abstract:
The objective of this study was to analyse and compare the thermal environment of dairy cattle facilities in an open compost bedded pack barn (CBP) with natural ventilation and closed CBP (without thermal insulation) and climate control system. The research was conducted in a property located in Zona da Mata, Minas Gerais, Brazil. During the summer and for different periods of the day, the following average environmental variables observed inside the facilities were measured: dry bulb temperature, relative humidity and Temperature and Humidity Index (THI). The results were submitted to an analysis of variance to determine the significance of the variables in the different treatments. It was found that the closed and climate control system CBP promoted greater control of the facility’s internal microclimate, registering smaller thermal amplitudes and a greater reduction in the animals’ exposure time to stressful thermal conditions, compared to the CBP with natural ventilation. However, during summer afternoons, comfort indices indicated moderate stress. It is concluded that the closed CBP, regarding the analysed variables, indicated potential use, provided that a careful study of the climate of the region is carried out before implementation, the factors related to the ambient conditioning and better insulation of the construction are adjusted. The climatic variables inside the open CBP indicated a high stress condition for the animals, suggesting the placement of positive pressure fans and sprinklers properly distributed in the feed alley, to guarantee benefits to the entire area of the animal housing.
Key words:
animal welfare, Housing systems, livestock farming, mechanical ventilation, thermal environment