Chronobiologic blood pressure assessment: maturation of the daily rhythm in newborn foals.

This research investigates the development of daily blood pressure rhythms in newborn horse foals over a period of 40 days. The study suggests that the horse foals do not fully develop a daily blood pressure rhythm during the first 40 days of their life.

Methods

• Seven newborn horse foals were observed over 40 days following their birth.
• Blood pressure measurements were taken using an oscillometric apparatus (Argus TM-7, Schiller, Barr Switzerland).
• The foals were standing during measurements, with the blood pressure cuff placed around their tail.
• Blood pressure was recorded twice a day, one hour before sunrise and one hour before sunset for the first ten days of their life.
• From the 11th to the 32nd, day blood pressure measurements were taken every two days, and then also on the 36th and 40th days.
• Two-way repeated measures analysis of variance (ANOVA) was used to determine statistically significant differences between the mean blood pressure values recorded at dawn and dusk during the study.

Results and Discussion

• The variance analysis showed a significant effect of time (p < 0.0001) during the first 40 days of life, suggesting that there are changes in blood pressure with respect to time since birth.
• The study confirmed a strong correlation between age and blood pressure in horses, indicating that blood pressure changes as foals age and grow.
• Contrary to expectations, the study found an absence of blood pressure rhythm maturation in foals that are 40 days old. This result implies that unlike some physiological processes, there is no daily cyclic pattern in the blood pressure of young foals at least during the first 40 days of their life.
• The findings provide valuable information about the development of circadian rhythms in mammals, particularly horses, which can be used for further research in this area.
• The results of this study help improve the understanding about the chronophysiological assessment of blood pressure in horses, which could potentially influence how health checks and medical interventions are carried out in these animals.