Roaring in Clydesdales.

The study investigated the movement of arytenoid cartilage during normal breathing in Clydesdale horses and whether certain physical characteristics could affect it, with abnormal movements noted in half of the horses over one year old. The researchers found no significant connection between these movements and factors such as sex, age, estimated weight, height, or neck length.

Endoscopic Survey of Clydesdale Horses

• The researchers performed an endoscopic survey, which involves inserting a flexible tube with a light and camera attached to its end into the horse’s respiratory airway (larynx), to observe the movement of the arytenoid cartilage during quiet respiration.
• The study involved 48 Clydesdale horses, a breed known for its stature and strength.

Recording Physical Characteristics

• Various physical characteristics, which could potentially influence the length of the recurrent laryngeal nerves (nerves supplying the muscles responsible for opening and closing the vocal cords), were recorded for each horse.
• These characteristics included the horse’s sex, age, estimated weight, height, and neck length.

Statistical Assessment

• The researchers statistically analyzed the data to determine if any of these physical characteristics correlated with abnormal left arytenoid cartilage movements.
• Abnormal movements were observed in 50% of the animals who were over one year of age.

Findings

• The results showed no significant correlation between the presence of abnormal arytenoid movements and the recorded physical characteristics.
• However, they did note that on average, affected horses were slightly taller, lighter and longer necked, suggesting that those particular traits may play a role in arytenoid’s abnormal movement, though, statistically, this was not significant.