Survey of resting blood pressure values in clinically normal horses.

This research looks at the resting blood pressure values in different types of healthy horses using indirect measures taken at the tail. The study found that blood pressure varies depending on the breed of the horse, with Thoroughbreds displaying higher values than Standardbreds and hacks. Factors like temperature and age showed an impact on the recorded blood pressure values. However, sex, height, or heart rate did not seem to influence blood pressure.

Research Methodology and Findings

• The study involved measuring resting coccygeal blood pressure values indirectly on 296 horses. There were 97 Thoroughbreds, 97 Standardbreds, and 102 hacks in the sample.
• The blood pressure measurements varied with the breed of the horse. On average, Thoroughbreds had significantly higher blood pressure values than Standardbreds and hacks. The blood pressure values of Standardbreds and hacks, however, showed no significant difference.
• The researchers found no discernable effect of sex, height, or heart rate on the horse’s blood pressure. Nevertheless, factors such as temperature and age played a role in influencing the measurement recorded.

Mean Values

• The mean uncorrected coccygeal values (systolic pressure/diastolic pressure) for the sample population were 112.1 +/- 16.5/77.3 +/- 14.3 mmHg.
• After accounting for variables like bladder width to tail girth ratios used in each measurement, the actual coccygeal pressures determined were 122.8 +/- 18.6/71.0 +/- 13.4 mmHg.
• These values corresponded to the values of 149.4 +/- 19.0/97.6 +/- 14.0 mmHg when corrected to heart (shoulder) level.

Normal Limits

• The researchers established the normal limits (defined as within the 2.5th and 97.5th percentiles) for all horses, regardless of their breed. These were 80 to 144 mmHg/49 to 105 mmHg for coccygeal uncorrected values.
• The normal limits adjusted for bladder width to tail girth ratio were 86 to 159 mmHg/45 to 97 mmHg.