The relationship between body condition score and ultrasonic fat measurements in mares of high versus low body condition
This study was conducted to correlate body condition score (BCS) in mares with ultrasonic measurements of subcutaneous fat taken at four locations (tailhead, rump, 13th rib, and withers), and to determine which site might be the most reliable area of measurement. Twenty-four light horse mares were assigned to either a high BCS group (8.0-9.0) or a low BCS group (3.0-3.5). From September to December 1999, mares were full grazed or restricted to reach their respective target BCS; they were then maintained at that BCS until the following May. Ultrasonic fat measurements were recorded every 14 days from September to May. Over time, mares in the low BCS group lost subcutaneous fat and mares in the high BCS group deposited subcutaneous fat at all four locations (P < .02). In both the high and low BCS groups, subcutaneous fat at the rump changed much less over the course of the experiment than did the amount of subcutaneous fat at the tailhead, 13th rib, and withers. Correlation coefficients (r) between BCS and subcutaneous fat thickness were: 0.87, 0.84, 0.82, and 0.86 for the tailhead, rump, 13th rib, and withers, respectively. The tailhead area accounted for the majority of the variation in BCS (R2 = 0.75). Overall, 78% of the variation could be accounted for when the 13th rib and withers were combined with the tailhead; however, the rump did not significantly contribute or account for variation. This study shows that body condition score and subcutaneous fat measurements are correlated, especially at the tailhead area. Application of the system developed by Henneke et al, 1 with particular emphasis on the amount of fat in areas such as the tailhead, 13th rib, and withers, can provide an accurate estimate of the condition and/or body fat content of a mare.
Publication Source (Journal or Book title)
Journal of Equine Veterinary Science
Gentry, L., Thompson, D., Gentry, G., Del Vecchio, R., Davis, K., & Del Vecchio, P. (2004). The relationship between body condition score and ultrasonic fat measurements in mares of high versus low body condition. Journal of Equine Veterinary Science, 24 (5), 198-203. https://doi.org/10.1016/j.jevs.2004.04.009