Please use this identifier to cite or link to this item: http://repositorio.ufla.br/jspui/handle/1/40359
Title: Thermal environment and physiological and productive parameters in laying hens: assessment and modeling
Other Titles: Ambiente térmico e parâmetros fisiológicos e produtivos de poedeiras: avaliação e modelagem
Authors: Yanagi Junior, Tadayuki
Campos, Alessandro Torres
Oliveira, Daniela Duarte de
Campos, Alessandro Torres
Baptista, Fátima de Jesus Folgôa
Julio, Yamid Fabián Hernández
Silva, Iran José Oliveira da
Lima, Renato Ribeiro de
Zangeronimo, Márcio Gilberto
Keywords: Avicultura de postura
Ambiência animal
Inteligência artificial
Modelos empíricos
Fisiologia de aves de postura
Faixas de conforto térmico
Laying poultry
Animal welfare
Artificial intelligence
Empirical models
Poultry physiology
Thermal comfort thresholds
Issue Date: 27-Apr-2020
Publisher: Universidade Federal de Lavras
Citation: RIBEIRO, B. P. V. B. Thermal environment and physiological and productive parameters in laying hens: assessment and modeling. 2020. 118 p. Tese (Doutorado em Engenharia Agrícola)-Universidade Federal de Lavras, Lavras, 2020.
Abstract: This study aimed to evaluate and model mathematically the effect of the thermal environment on the physiological responses of laying hens. The study was conducted in four air-conditioned wind tunnels, where ninety laying hens in peak production phase, aged 28 weeks, were housed individually in a cage and subjected to different thermal challenges. The birds were subjected to the factorial combination of five dry air bulb temperatures (tbs: 20, 24, 28, 32 and 36ºC), two levels of relative humidity (RH: 40 and 60%) and three air velocities (V: 0.2, 0.7 and 1.4 m s-1), totaling 30 thermal challenges. The physiological responses surface temperature (tsurface), cloacal temperature (tcloacal) and respiratory rate (RR) were measured at 10 min intervals during each experimental test (thermal challenge), with a minimum duration of three hours and a maximum duration of six hours. Empirical models were adjusted and models based on artificial intelligence (Artificial Neural Network - ANNs and fuzzy systems) were developed to predict the physiological responses of laying hens as a function of the variables that characterize the different thermal challenges. In addition, thermal comfort ranges have been established for birds as a result of these variables. Through the analysis of clusters, empirical models and graphics with thermal comfort bands for Hy Line laying hens, it can be inferred that, in a controlled experimental environment, the comfort bands found are close to those specified by the literature. The development of models based on artificial intelligence (fuzzy and ANNs) mainly due to the climatic variables, tbs, RH, V, obtained adequate adjustments to predict the tcloacal, tsurface and RR physiological variables.
URI: http://repositorio.ufla.br/jspui/handle/1/40359
Appears in Collections:Engenharia Agrícola - Doutorado (Teses)



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