title: Influence of environmental factors on infrared eye temperature measurements in cattle.
abstract: Environmental factors were evaluated to determine potential limitations in using cattle eye temperatures obtained through infrared thermography (IRT) for early disease detection systems or in animal welfare research studies. The effects of the following factors on IRT eye temperatures in cattle and a fabricated surrogate "eye" were evaluated: camera to object distance, wind speed, camera settings (distance, emissivity, and humidity), and solar loading. Wind speed in both live animals and using a surrogate "eye" was found to decrease the IRT temperature. In the presence of ∼ 7 km/h wind, the mean IRT eye temperature decreased by 0.43 ± 0.13 °C and; at higher wind speeds (∼ 12 km/h), the temperature decreased by 0.78 ± 0.33 °C. Direct sunlight was found to increase the IRT eye temperature by 0.56 ± 0.36 °C. It was determined that environmental factors impact IRT temperature measurements significantly and therefore must be managed to ensure reproducible and accurate readings.
authors.affiliation: Thompson Rivers University, 900 McGill Road, Kamloops, British Columbia V2C 0C8, Canada. Electronic address: jchurch@tru.ca.
authors.forename: J S
authors.initials: JS
authors.lastname: Church
authors.affiliation: Thompson Rivers University, 900 McGill Road, Kamloops, British Columbia V2C 0C8, Canada.
authors.forename: P R
authors.initials: PR
authors.lastname: Hegadoren
authors.affiliation: Thompson Rivers University, 900 McGill Road, Kamloops, British Columbia V2C 0C8, Canada.
authors.forename: M J
authors.initials: MJ
authors.lastname: Paetkau
authors.affiliation: Department of Medicine, Respiratory Division, University of British Columbia, Vancouver, British Columbia V5Z 3J5, Canada.
authors.forename: C C
authors.initials: CC
authors.lastname: Miller
authors.affiliation: Department of Medicine, Respiratory Division, University of British Columbia, Vancouver, British Columbia V5Z 3J5, Canada.
authors.forename: G
authors.initials: G
authors.lastname: Regev-Shoshani
authors.affiliation: Agriculture and Agri-Food Canada, 6000 C and E trail, Lacombe, Alberta T4L 1W1, Canada.
authors.forename: A L
authors.initials: AL
authors.lastname: Schaefer
authors.affiliation: Agriculture and Agri-Food Canada, Lethbridge Research Centre, 5304 - 1st Avenue South, Lethbridge, Alberta T1J 4B1, Canada.
authors.forename: K S
authors.initials: KS
authors.lastname: Schwartzkopf-Genswein
mesh_terms: D000818:Animals; D001831:Body Temperature / Q000502:physiology*; D002417:Cattle / Q000502:physiology*; D005260:Female; D008297:Male; D009799:Ocular Physiological Phenomena; D012044:Regression Analysis; D013472:Sunlight; D013817:Thermography / Q000662:veterinary*; D014919:Wind
keywords: Environment; Eye temperature; Infrared thermography; Welfare