Tag Archives: thermal environment

1049-1057 R.R. Andrade, I.F.F. Tinôco, F.A. Damasceno, D.A. Valente, C.E.A. Oliveira, V.C. Oliveira, G. Rossi and M. Barbari
Analysis of environmental conditions in two different Compost Bedded Pack Barn systems for dairy cattle
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Analysis of environmental conditions in two different Compost Bedded Pack Barn systems for dairy cattle

R.R. Andrade¹, I.F.F. Tinôco², F.A. Damasceno³, D.A. Valente², C.E.A. Oliveira², V.C. Oliveira², G. Rossi⁴ and M. Barbari⁴

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.

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704–710 P.F.P. Ferraz, G.A.S. Ferraz, M. Barbari, M.A.J.G. Silva, F.A. Damasceno, D. Cecchin and J.O. Castro
Behavioural and physiological responses of rabbits
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Behavioural and physiological responses of rabbits

P.F.P. Ferraz¹*, G.A.S. Ferraz¹, M. Barbari², M.A.J.G. Silva¹, F.A. Damasceno¹, D. Cecchin³ and J.O. Castro¹

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
³Federal University Fluminense, Department of Agricultural Engineering and Environment, Campus Praia Vermelha, São Domingos, BR24.210-240 Niterói, Rio de Janeiro, Brazil
*Correspondence: patricia.ponciano@deg.ufla.br

Abstract:

The profitability of a rabbit farming system must consider the thermal environment that the animal will be exposed during the productive period. The goal of this study was to evaluate the physiological responses and behaviours of 26 New Zealand rabbits during seven days of their lives at three times a day. The experiment was carried out in rabbit house in the Federal University of Lavras at Lavras, Brazil. To characterize the thermal environment sensors were used to measure the dry bulb temperature and relative humidity at 48 points inside the rabbit house, at 6:00 a.m., 12:00 a.m. and 6:00 p.m. In addition, the temperature and humidity index (THI) was calculated. The respiratory rate and the superficial temperature of the rabbits’ ears were measured. Behaviour evaluations were monitored in punctual record, with duration of two min/cage. Later an ethogram was made with the main behaviours identified. Similar data of behaviour and data of physiological responses were identified by using Ward’s method of cluster analysis. It was observed the period of 6 a.m. showed more comfortable conditions of THI values than the others analysed. Besides, physiological responses presented better values at 6:00 a.m. in comparison to 12:00 and 6:00 p.m. Furthermore, in general, a similar behaviour was observed in the rabbits at 12:00 and 6:00 p.m., while at 6:00 a.m. was different. But rabbits demonstrated to be more comfortable at 6 a.m. maybe because at this time environment conditions were better than the rest of the day. Besides, it can be observed that rabbits were more active in sunrise and sunset than in the rest of the day.

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872–878 C.G.S. Teles Jr., R.S. Gates, M. Barbari, L. Conti, G. Rossi, M.O. Vilela, C.F.F. Souza and I.F.F. Tinôco
A software to estimate heat stress impact on dairy cattle productive performance
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A software to estimate heat stress impact on dairy cattle productive performance

C.G.S. Teles Jr.¹, R.S. Gates², M. Barbari³*, L. Conti³, G. Rossi³, M.O. Vilela¹, C.F.F. Souza¹ and I.F.F. Tinôco¹

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 Illinois, Department of Agricultural and Biological Engineering, 1304 West Pennsylvania Avenue, US61820, Urbana-IL, United States of America
³University of Florence, Department of Agriculture, Food, Environment and Forestry, Via San Bonaventura, 13, IT50145 Firenze, Italy
*Correspondence: matteo.barbari@unifi.it; carlosgutembergjr@hotmail.com

Abstract:

The aim of this study is to develop a computational tool, based on the Temperature and Humidity Index value, to characterize the thermal environment in dairy cattle barns and to evaluate the impact of thermal stress on productive performance. The software for the thermal environment prediction, and determination of the influence of heat stress on dairy cow productivity (Ambi + Leite) was developed using the C# programming language in the Microsoft Visual C# 2010 Express Integrated Development Environment. The following scenario was considered for the program test: air temperature 32°C, relative air humidity 70% and milk production potential in thermoneutrality condition 20 kg cow-1 day-1. The prediction of the thermal environment based on the simulated situations indicates that the animals are submitted to a moderate heat stress condition with THI equal to 82.81. In this condition a decrease of approximately 26% in milk production and a reduction of 4 kg cow-1 day-1 in food intake was calculated. In conclusion, the developed software can be a practical tool to assist the producer in making-decision processes.

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