title: Mapping the body surface temperature of cattle by infrared thermography.
abstract: Infrared thermography (IRT) is an alternative non-invasive method that has been studied as a tool for identifying many physiological and pathological processes related to changes in body temperature. The objective of the present study was to evaluate the body surface temperature of Jersey dairy cattle in a thermoneutral environment in order to contribute to the determination of a body surface temperature pattern for animals of this breed in a situation of thermal comfort. Twenty-four Jersey heifers were used over a period of 35 days at APTA Brazil. Measurements were performed on all animals, starting with the physiological parameters. Body surface temperature was measured by IRT collecting images in different body regions: left and right eye area, right and left eye, caudal left foreleg, cranial left foreleg, right and left flank, and forehead. High correlations were observed between temperature and humidity index (THI) and right flank, left flank and forehead temperatures (0.85, 0.81, and 0.81, respectively). The IRT variables that exhibited the five highest correlation coefficients in principal component 1 were, in decreasing order: forehead (0.90), right flank (0.87), left flank (0.84), marker 1 caudal left foreleg (0.83), marker 2 caudal left foreleg (0.74). The THI showed a high correlation coefficient (0.88) and moderate to low correlations were observed for the physiological variables rectal temperature (0.43), and respiratory frequency (0.42). The thermal profile obtained indicates a surface temperature pattern for each region studied in a situation of thermal comfort and may contribute to studies investigating body surface temperature. Among the body regions studied, IRT forehead temperature showed the highest association with rectal temperature, and forehead and right and left flank temperatures are strongly associated with THI and may be adopted in future studies on thermoregulation and body heat production.
authors.affiliation: Agência Paulista de Tecnologia dos Agronegócios (APTA Ribeirão Preto), Brazil. Electronic address: marciasalles@apta.sp.gov.br.
authors.forename: Marcia Saladini Vieira
authors.initials: MS
authors.lastname: Salles
authors.affiliation: Agência Paulista de Tecnologia dos Agronegócios (APTA Ribeirão Preto), Brazil.
authors.forename: Suelen Corrêa
authors.initials: SC
authors.lastname: da Silva
authors.affiliation: Agência Paulista de Tecnologia dos Agronegócios (APTA Ribeirão Preto), Brazil.
authors.forename: Fernando André
authors.initials: FA
authors.lastname: Salles
authors.affiliation: Agência Paulista de Tecnologia dos Agronegócios (APTA Ribeirão Preto), Brazil.
authors.forename: Luiz Carlos
authors.initials: LC
authors.lastname: Roma
authors.affiliation: Agência Paulista de Tecnologia dos Agronegócios (APTA Ribeirão Preto), Brazil.
authors.forename: Lenira
authors.initials: L
authors.lastname: El Faro
authors.affiliation: Faculdade de Zootecnia e Engenharia dos Alimentos (FZEA USP Pirassununga), Brazil.
authors.forename: Priscilla Ayleen
authors.initials: PA
authors.lastname: Bustos Mac Lean
authors.affiliation: Faculdade de Zootecnia e Engenharia dos Alimentos (FZEA USP Pirassununga), Brazil.
authors.forename: Celso Eduardo
authors.initials: CE
authors.lastname: Lins de Oliveira
authors.affiliation: Faculdade de Zootecnia e Engenharia dos Alimentos (FZEA USP Pirassununga), Brazil.
authors.forename: Luciane Silva
authors.initials: LS
authors.lastname: Martello
mesh_terms: D000818:Animals; D001831:Body Temperature; D002417:Cattle / Q000502:physiology*; D005260:Female; D007091:Image Processing, Computer-Assisted; D007259:Infrared Rays; D012815:Signal Processing, Computer-Assisted; D013499:Surface Properties; D013817:Thermography / Q000379:methods*
keywords: Infrared thermography; Non-invasive method; Physiology; Ruminants