The aim of the study was to determine the relationship of rectal temperature and respiratory frequency with hair surface temperature (head, shoulder, paralumbar fossa, hip and belly) obtained through thermographic images in hair ewes pregnant and heat-stressed. Variables were collected every 15 days twins daily (07:00 and 16:00 h) in 24 Katahdin x Pelibuey pregnant multiparous ewes, starting from day 100 of pregnancy to lambing. Statistical analyses were Pearson correlation and simple linear regression. Rectal temperature (r = 0.66 a 0.74) and respiratory frequency (r = 0.60 a 0.66) were positively correlated (P < 0.0001) with the different hair coat temperatures. The equations developed with each hair coat temperature explained (P < 0.0001) between 36 and 55 % of the variation observed in the rectal temperature and respiratory frequency. Head temperature explained the highest variation (R² = 0.48 to 0.55) in both physiological variables. It was concluded that hair surface temperatures have a moderate relationship with rectal temperature and respiratory frequency in hair pregnant ewes maintained in hyperthermia; likewise, head temperature can be used in the development of prediction equation for both physiological variables.

Vicente‑Pérez R, Macías‑Cruz U, Avendaño‑Reyes L, Correa‑Calderón A, Luna‑Palomera C, Chay‑Canul AJ (2019). Relación de temperatura rectal y frecuencia respiratoria con temperaturas de pelo obtenidas por termografía en ovejas gestantes estresadas por calor. ITEA‑Información Técnica Económica Agraria 115(3): 219‑230. https://doi.org/10.12706/itea.2018.035