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dc.contributor.authorMilan, H. F. M.
dc.contributor.authorMaia, A. S. C. [UNESP]
dc.contributor.authorGebremedhin, K. G.
dc.identifier.citationTransactions Of The Asabe. St Joseph: Amer Soc Agricultural & Biological Engineers, v. 62, n. 2, p. 321-342, 2019.
dc.description.abstractThe thermal environment of farrowing facilities is generally controlled at the thermo-neutral zone for sows (15 degrees C to 19 degrees C). This imposes thermal challenges for newborn piglets, which are thermally comfortable at temperatures 10 degrees C to 20 degrees C higher (32 degrees C to 35 degrees C). To satisfy the energetic requirements of piglets, supplemental heat is installed in creep or brooder areas. In this study, we determined optimum supplemental heat requirements (supplied by heating lamps) for piglets based on energy balance as a function of air temperature and animal body weight. We also determined the zone of least thermoregulation of piglets for a given weight when supplemental heat is not provided. Energy balance was calculated using an ensemble of mechanistic models of bio-heat transfer that predicts hair-coat temperature, skin temperature, and skin heat flux. Inputs to the ensemble of mechanistic models include air temperature, black-globe temperature, rectal temperature, and system parameters (e.g., thickness of internal tissues and thermal conductivities). Input temperatures were predicted from measured air temperature in the pen and supplemental heat using machine learning. System parameters were measured or obtained from the literature and optimized using the Monte Carlo method. Ensemble predictions of hair-coat and skin temperature agreed within 3.5% with measured data. The ensemble-predicted zone of least thermoregulation agreed well with previous reports. Predicted optimum supplemental heat showed an exponential decay trend with increasing air temperature and/or animal weight. For air temperature between 15 degrees C and 19 degrees C, the predicted optimum supplemental heat was 266 to 344 W and 44 to 128 W for piglets weighing 1 kg and 20 kg, respectively. The predicted optimum supplemental heat was similar to 200 W lower for piglets at the end of the farrowing cycle (assuming weight of 20 kg) than at birth (assuming birth weight of 1 kg).en
dc.description.sponsorshipConselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
dc.description.sponsorshipFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
dc.description.sponsorshipUSDA Hatch funds as part of the Regional Project through Cornell University
dc.publisherAmer Soc Agricultural & Biological Engineers
dc.relation.ispartofTransactions Of The Asabe
dc.sourceWeb of Science
dc.subjectBio-heat equation
dc.subjectComputational models
dc.subjectEnsemble learning
dc.subjectPrecision livestock farming
dc.subjectSupplemental heat
dc.subjectThermo-neutral zone
dcterms.rightsHolderAmer Soc Agricultural & Biological Engineers
dc.contributor.institutionCornell Univ
dc.contributor.institutionUniversidade Estadual Paulista (UNESP)
dc.description.affiliationCornell Univ, Dept Biol & Environm Engn, Ithaca, NY USA
dc.description.affiliationSao Paulo State Univ, Dept Anim Sci, Jaboticabal, Brazil
dc.description.affiliationUnespSao Paulo State Univ, Dept Anim Sci, Jaboticabal, Brazil
dc.rights.accessRightsAcesso restrito
dc.description.sponsorshipIdCNPq: 203312/2014-7
dc.description.sponsorshipIdFAPESP: 17.519/14
dc.description.sponsorshipIdUSDA Hatch funds as part of the Regional Project through Cornell University: W-3173[2][2]
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