Feeble weekly rhythmicity in hematological, cardiovascular, and thermal parameters in the horse.
- Journal Article
- Research Support
- U.S. Gov't
- Non-P.H.S.
- Research Support
- U.S. Gov't
- P.H.S.
Summary
The research study investigates the presence of weak, seven-day rhythms in certain biological parameters of athletic and sedentary horses. Despite the potential impact of weekly activity schedules, the evidence found does not support the concept of naturally occurring week-long rhythms in these animals.
Study Overview
In this study, the researchers set out to examine whether there are regular, week-long patterns in certain physiological factors of horses. This concept, known as circaseptan rhythms, refers to an internal biological rhythm with a period of approximately one week. Specifically, they focused on:
- The plasma concentration of lactic acid
- Systolic and diastolic blood pressure
- Rectal temperature
These parameters were compared in two groups of horses: athletic horses that followed a seven-day training schedule and sedentary horses that had a constant schedule without any significant change throughout the week.
Key Findings
The results showed that while exercise, unsurprisingly, had a strong immediate effect on the parameters studied, only one parameter (plasma concentration of lactic acid) exhibited any kind of weekly rhythmicity, and even then, it was only present in a few athletic horses. Furthermore, this weak pattern vanished when more strict statistical criteria were applied.
Interestingly, the study found that all parameters showed 24-hour rhythmicity (circadian rhythms) in all horses, athletic and sedentary alike. This suggests that a regular daily cycle, rather than a weekly one, may be more influential on these physiological parameters in horses.
Conclusion
In conclusion, the researchers determined that the weekly patterns observed in the physiological parameters of the horses were weak and likely resulted from the structured weekly activity schedule. The evidence thus does not support the theory of an innate, seven-day rhythmicity in these animals. Instead, the findings suggest that daily patterns, and the immediate impact of exercise, are more strongly associated with fluctuations in these physiological parameters.
Cite This Article
Publication
Researcher Affiliations
- Dipartimento di Morfologia, Biochimica, Fisiologia e Produzioni Animali, Facoltà di Medicina Veterinaria, Università degli Studi di Messina, Messina, Italy.
MeSH Terms
- Animals
- Biological Clocks / physiology
- Blood Pressure / physiology
- Body Temperature / physiology
- Female
- Homeostasis
- Horses / blood
- Horses / physiology
- Lactic Acid / blood
- Periodicity
- Physical Conditioning, Animal
- Physical Exertion / physiology
Grant Funding
- MH-66826 / NIMH NIH HHS
Citations
This article has been cited 5 times.- Stachurska A, Kędzierski W, Kaczmarek B, Wiśniewska A, Żylińska B, Janczarek I. Variation of Physiological and Behavioural Parameters during the Oestrous Cycle in Mares. Animals (Basel) 2023 Jan 6;13(2).
- Refinetti R. Circadian rhythmicity of body temperature and metabolism. Temperature (Austin) 2020;7(4):321-362.
- Larsson J, Pilborg PH, Johansen M, Christophersen MT, Holte A, Roepstorff L, Olsen LH, Harrison AP. Physiological parameters of endurance horses pre- compared to post-race, correlated with performance: a two race study from scandinavia. ISRN Vet Sci 2013;2013:684353.
- Wiater MF, Li AJ, Dinh TT, Jansen HT, Ritter S. Leptin-sensitive neurons in the arcuate nucleus integrate activity and temperature circadian rhythms and anticipatory responses to food restriction. Am J Physiol Regul Integr Comp Physiol 2013 Oct 15;305(8):R949-60.
- Li AJ, Wiater MF, Oostrom MT, Smith BR, Wang Q, Dinh TT, Roberts BL, Jansen HT, Ritter S. Leptin-sensitive neurons in the arcuate nuclei contribute to endogenous feeding rhythms. Am J Physiol Regul Integr Comp Physiol 2012 Jun;302(11):R1313-26.
