Tag Archives: thermal comfort

xxx J.O. Castro, T. Yanagi Junior, A.L. Abreu, P.F.P. Ferraz, G.B. Moura, D. Cecchin and L. Conti
Use of thermography for the evaluation of the surface temperature of Japanese Quail submitted at different temperatures
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Use of thermography for the evaluation of the surface temperature of Japanese Quail submitted at different temperatures

J.O. Castro¹, T. Yanagi Junior¹, A.L. Abreu², P.F.P. Ferraz¹, G.B. Moura¹, D. Cecchin³* and L. Conti⁴

¹Federal University of Lavras, Agricultural Engineering Department, Campus Universitário, PO Box 3037 Lavras, Minas Gerais, Brazil
²Federal University of Lavras, Agricultural Department, Campus Universitário, PO Box 3037 Lavras, Minas Gerais, Brazil
³Federal University Fluminense, Department of Agricultural Engineering and Environment, Campus Praia Vermelha, São Domingos, Niterói, BR24.210-240 Rio de Janeiro, Brazil
⁴University of Firenze, Department of Agriculture, Food, Environment and forestry (DAGR), Via San Bonaventura, 13, IT50145 Firenze, Italy
*Correspondence: patricia.ponciano@ufla.br

Abstract:

Thermography has been gaining more space in analyzes of the superficial thermal profile of birds since it is a non-invasive way of evaluating thermal comfort. This study aims to evaluate the influence of different air temperatures (tair) from 20 °C to 32 °C on the maximum, average and minimum surface temperature (STmax, STaverage and STmin) of Japanese laying quails. The experiment was performed in four wind tunnels, where the continuous air temperature within each tunnel, 20 °C, 22 °C, 24 °C, 26 °C, 28 °C, 30 °C and 32 °C represented treatment, with 20 °C being the control treatment. Two experiments, of 21 days each, were carried out. For each experiment, we used four replicates and eight quails in each repetition, in a completely randomized design. Thermographic images of each repetition were made weekly through the Fluke Ti55 camera and analyzed using SmartView® software. The STmax, STaverage and STmin of each repetition were obtained by delimiting the area of the quails within the cages. Significant differences were observed between ST as the room temperature increased. The ST of quails behaved similarly from 28 °C on. Both head and feet had higher temperatures. It was possible to verify that air temperatures above 22 °C promoted an increase in the maximum, average and minimum surface temperatures. The highest surface temperatures are found in the head and foot region.

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408–417 P.F.P. Ferraz, G.A.S. Ferraz, L. Schiassi, V.H.B. Nogueira, M. Barbari and F.A. Damasceno
Spatial variability of litter temperature, relative air humidity and skin temperature of chicks in a commercial broiler house
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Spatial variability of litter temperature, relative air humidity and skin temperature of chicks in a commercial broiler house

P.F.P. Ferraz¹*, G.A.S. Ferraz¹, L. Schiassi¹, V.H.B. Nogueira¹, M. Barbari² and F.A. Damasceno¹

¹Federal University of Lavras, Agricultural Engineering Departament, Campus Universitário, PO Box 3037, Lavras, Minas Gerais, Brazil
²University of Firenze, Department of Agriculture, Food, Environment and Forestry, Via San Bonaventura, 13, IT50145 Firenze, Italy
*Correspondence: patricia.ponciano@ufla.br

Abstract:

The thermal environment inside a broiler house has a great influence on animal welfare and productivity during the production phase. Among the importance of the chicken litter is the function of absorbing moisture, provide thermal insulation and provide a soft surface for broilers. The skin temperature is an important physiological parameter to quantify the thermal comfort of animals, its variations may occur as a function of thermal variables. So, the aim of this work was to analyse the magnitude and spatial variability of chicken litter temperature and relative humidity of the air and to correlate them with the spatial distribution of chicks’ skin surface temperature throughout the broiler house during the 7th, 14th and 21st days of the chicks’ life, using geostatistical techniques. The experiment was performed in a commercial broiler house located in the western mesoregion of Minas Gerais, Brazil, where 28,000 male Cobb chicks were housed. The heating system consisted of an industrial indirect-fired biomass furnace. The heated air was inflated by an AC motor, 2,206 W of power, 1,725 RPM. Geostatistical techniques were used through semivariogram analysis and isochore maps were generated through data interpolation by kriging. The semivariogram was fitted by the restricted maximum likelihood method. The used mathematical model was the spherical one. After fitting the semivariograms, the data were interpolated by ordinary kriging. The semivariograms along with the isochore maps allowed identifying the non-uniformity of spatial distribution of the broiler litter temperature throughout the broiler house for 3 days of chicks’ life. It was observed that skin surface presented a positive correlation with the litter temperature and a negative correlation with the air humidity. The semivariograms along with the isochore maps allowed identifying the non-uniformity of spatial distribution of the litter temperature, air humidity and skin temperature of chicks throughout the broiler aviary for the three days. In addition, the use of geostatistics and distribution maps made possible to identify different environmental conditions in regions inside the broiler house that may harm the development of chicks.

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900–906 H.H.R. Zanetoni, I.F.F. Tinôco, M. Barbari, L. Conti, G. Rossi, F.C. Baêta, M.O. Vilela, C.G.S. Teles Junior and R.R. Andrade
Alternative form to obtain the black globe temperature from environmental variables
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Alternative form to obtain the black globe temperature from environmental variables

H.H.R. Zanetoni¹*, I.F.F. Tinôco¹, M. Barbari²*, L. Conti², G. Rossi², F.C. Baêta¹, M.O. Vilela¹, C.G.S. Teles Junior¹ and R.R. Andrade¹

¹Federal University of Viçosa, Department of Agricultural Engineering, Av. Peter Henry Rolfs, s/n Campus University of Viçosa CEP: 36570-900, Viçosa, Minas Gerais, Brazil
²University of Florence, Department of Agricultural, Food, Environmental and Forestry Science, Via San Bonaventura, 13, IT50145 Firenze, Italy
*Correspondence: matteo.barbari@unifi.it; hiago.zanetoni@ufv.br

Abstract:

Reaching thermal comfort conditions of animals is essential to improve well-being and to obtain good productive performance. For that reason, farmers require tools to monitor the microclimatic situation inside the barn. Black Globe-Humidity Index (BGHI) acts as a producer management tool, assisting in the management of the thermal environment and in decision making how protect animals from heat stress. The objective of this work was to develop a mathematical model to estimate the black globe temperature starting from air temperature, relative humidity and air velocity. To reach this goal, data of air temperature and humidity were collected, with the aid of recording sensors. The black globe temperature was measured with a black copper globe thermometer and the air velocity was monitored with a hot wire anemometer. Data were analysed using a regression model to predict the black globe temperature as a function of the other variables monitored. The model was evaluated, based on the significance of the regression and the regression parameters, and the coefficient of determination (). The model proved to be adequate for the estimation of the black globe temperature with R2 = 0.9166 and the regression and its parameters being significant (p < 0.05). The percentage error of the model was low (approximately 2.2%). In conclusion, a high relation between the data estimated by the model with the data obtained by the standard black globe thermometer was demonstrated.

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687–693 L.C.S.R. Freitas, I.F.F. Tinôco, F.C. Baêta, M. Barbari, L. Conti, C.G.S. Teles Júnior, M.G.L. Cândido, C.V. Morais and F.C. Sousa
Correlation between egg quality parameters, housing thermal conditions and age of laying hens
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Correlation between egg quality parameters, housing thermal conditions and age of laying hens

L.C.S.R. Freitas¹, I.F.F. Tinôco¹, F.C. Baêta¹, M. Barbari²*, L. Conti², C.G.S. Teles Júnior¹, M.G.L. Cândido¹, C.V. Morais¹ and F.C. Sousa¹

¹ Federal University of Viçosa, Department of Agricultural Engineering, Avenue Peter Henry Rolfs, University Campus, BR36570-900, Viçosa-MG, Brazil
² University of Firenze, Department of Agricultural, Food and Forestry Systems, Via San Bonaventura, 13, IT50145 Firenze, Italy
*Correspondence: matteo.barbari@unifi.it; leticia.ramos@ufv.br

Abstract:

High environmental temperatures cause a decrease in feed consumption by laying hens and, as a consequence, a reduction of productive performance and egg weight. The hens age is a factor influencing the albumen quality that tends to be more liquefied in older hens. Such variable is analysed by the determination of the Haugh Unit.
The correlations between the egg quality variables (egg weight and Haugh Unit), the  thermohygrometric conditions in the facility and the age of laying hens were determined in the study and evaluated based on the Pearson correlation coefficient (r) and their significance at the 5% level. The microclimatic data and the eggs were collected in 20 points of poultry facility with birds of 43, 56, 69, 79 and 86 weeks of age, totalling 100 samples.
The results show significant correlations between egg weight and temperature (r = -0.238), egg weight and hens age (r = 0.310), Haugh Unit index and hens age (r = -0.256); a non-significant correlation between the quality parameters with the relative humidity of the air inside the barn. The egg weight had a weak negative correlation with the ambient temperature and a weak positive correlation with the hens age. Concerning the Haugh Unit, a weak negative correlation with the age of the animals was found. The weak or non-existent correlation of temperature with egg quality parameters can be due to the environmental conditions that remained in the range of thermal comfort for the animals during the trials.

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237-244 M. Zajicek, and P. Kic
Heating of large agricultural and industrial buildings
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Heating of large agricultural and industrial buildings

M. Zajicek¹,* and P. Kic²

¹Institute of Information Theory and Automation, The Academy of Science of The Czech Republic, v.v.i.; *Correspondence: zajicek@utia.cas.cz 2Czech University of Life Sciences Prague, Faculty of Engineering, Czech Republic

Abstract:

This paper presents the results of the simulation calculations used in the selection and design of an appropriate method of heating of large buildings for agricultural or industrial purposes. These halls are characterized by a large built-up area, large room height and high consumption of energy for heating. The aim of the simulation calculation was to find a way of heating, which leads to a reduction in energy consumption while maintaining the required thermal comfort of indoor environment. The calculations were performed using the CFD software ANSYS-Fluent. For comparison of variants, a 3D model was used, including a heat source, natural convection and heat transfer through surrounding structures. The results of the thermal comfort of the working environment in the level of people or the growing zone of plants or the storage space for goods were mainly studied. The second area of interior space, especially important in terms of heat losses, is the level of the ceiling. The results of the calculations provide a detailed analysis of the vertical temperature profiles and the effect of the surrounding walls surface temperature on the thermal state of an indoor environment. The created model was verified according to the results of experiments in large buildings equipped with different heating systems. Based on the results of the simulation calculations and according to the results of experimental measurements, radiant heating method seems to be the suitable heating system solution for studied types of buildings.

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