Comparison of daily rhythm of rectal and auricular temperatures in horses kept under a natural photoperiod and constant darkness

Comparison of cortisol and rectal temperature circadian rhythms in horses: the role of light/dark cycle and constant darkness

“…Also, our results confirmed the circadian rhythm of rectal temperature reported in previous studies on horses (Piccione and Refinetti 2003;Piccione et al 2011aPiccione et al , 2011b and the stability of this rhythm in the absence of environmental cues (Piccione et al 2002). It showed oppose pattern respect to cortisol circadian rhythm, its acrophase was observed in the evening (22:55 L/D cycle -21:17 constant darkness) and its trough in the morning, at about 09:00.…”

“…The widely studied parameters used as an indicator of the rhythmicity of the biological clock is the rhythmicity of body temperature (Zulley et al 1981;Klerman et al 2002). Mainly, in various species, the rhythm of rectal temperature was simultaneously studied with the rhythm of activity (Refinetti 2006;Piccione et al 2011a), and as a marker to identify new body temperature recording point in horses and dogs (Piccione et al 2011b(Piccione et al , 2011c.…”

Comparison of rectal and vaginal temperature daily rhythm in dogs (Canis familiaris) under different photoperiod

“…On the contrary, vaginal temperature did not show daily rhythmicity, which reappeared during the D/D period. Contrary to that observed in horses subjected to D/D in which the acrophase of rectal temperature was anticipate of about 2 h respect to the L/D conditions (Piccione, Giannetto, Marafioti et al 2011), during the D/D cycle, the rhythm of rectal temperature maintained the same characteristics showed during the L/D and L/L period, and vaginal temperature reappeared showing rhythmic parameters overlapping to that observed during the L/D cycle. The average values of the free-running period as well as its inter-individual variability depend on the species under study (Refinetti 2006).…”

“…In dogs, goats and horses Piccione, Giannetto, Marafioti et al 2011), daily rhythm of rectal temperature was compared to daily rhythmicity of auricular temperature. In particular, in dogs, auricular temperature daily rhythm accurately reflects body temperature daily rhythm, it has a similar trend of rectal temperature; it shows the same robustness and acrophase of rectal temperature .…”

Constant darkness disrupt daily rhythm of adrenocorticotrophin in horses

“…In horses, it has been established that several physiological parameters are under L/D control (Piccione et al 2005(Piccione et al , 2008(Piccione et al , 2009(Piccione et al , 2011a(Piccione et al , 2012a.…”