Optimal sampling interval for characterisation of the circadian rhythm of body temperature in homeothermic animals using periodogram and cosinor analysis.

Core body temperature ( ) is a critical aspect of homeostasis in birds and mammals and is increasingly used as a biomarker of the fitness of an animal to its environment. Periodogram and cosinor analysis can be used to estimate the characteristics of the circadian rhythm of from data obtained on loggers that have limited memory capacity and battery life. The sampling interval can be manipulated to maximise the recording period, but the impact of sampling interval on the output of periodogram or cosinor analysis is unknown.

Immunolocalization of aquaporins 1, 3, and 5 in the nasal respiratory mucosa of a panting species, the sheep (Ovis aries).

The nasal respiratory mucosa is the primary site for evaporative water loss in panting species, necessitating the movement of water across the nasal epithelium. Aquaporins (AQP) are protein channels that facilitate water movement in various fluid transporting tissues of non-panting species. Whether the requirement for enhanced capacity for transepithelial water movement in the nasal respiratory mucosa of panting species has led to differences in AQP localization is unknown.

The cranial arterio-venous temperature difference is related to respiratory evaporative heat loss in a panting species, the sheep (Ovis aries).

Panting is a mechanism that increases respiratory evaporative heat loss (REHL) under heat load. Because REHL uses body water, it is physiologically and ecologically relevant to know under what conditions free-ranging animals use panting. We investigated whether the cranial arterio-venous temperature difference could provide information about REHL.