Changes in Hair Coat Length and Diameter in Blanketed and Non-Blanketed Adult Horses in the Winter.

Abstract

Horses are often blanketed during cold weather for numerous reasons including assisting thermoregulation, cleanliness, and anecdotally to decrease hair coat length. However, the impact of blanketing on the hair coat has yet to be evaluated. The objective of this study was to evaluate changes in hair coat length and diameter over time in blanketed and non-blanketed horses during winter. In October 2019, 16 mature adult horses were blocked by breed and BCS and randomly assigned to a blanketed (n=8) or non-blanketed (n=8) treatment; blankets were placed. Data was collected between October 2019 and March 2020 in River Falls, WI. During this time BW, BCS, and hair coat samples were taken monthly. Twenty hair coat samples were taken from the non-mane side of the neck and the hindquarters using a tweezers and measured for the length and diameter using a digital micrometer and caliper, respectively. The average measurement was used to analyze the data. Horse neck and hindquarter hair were the longest and had the greatest diameter in January and February and they were the shortest with the smallest diameter in October and March regardless of treatment (P ≤ 0 .05). Blanketed horses had shorter neck hair length when compared to non-blanketed horses in January at 43 and 58 mm, respectively, and February at 35 and 47 mm, respectively (P ≤ 0 .05). These results suggest blanketing a horse can alter hair coat length, however, hair coat growth over time follows a similar pattern regardless of blanketing practices.