This is the second in a series of educational posts to help horse owners get to know their horses. This post will explain why you should know your horse’s body weight and what you can measure in order to calculate it.
You should have a fairly accurate weight of your horse for several reasons such as: dosing medications, supplements and dewormers. Also, to monitor weight gains or losses for health reasons or to help adjust the amount of feed they are receiving.
This most accurate way to get the correct weight of your horse is to use a calibrated weight scale and since most of us do not have a scale, we depend on other methods. The method most often used is a height and weight tape. The tape measures the heart girth (around the horse’s body at the withers) however, the tape does not take body length into consideration and we know that a tall horse can be short backed and a short horse can have a long body. There are also different tapes specifically for ponies, horses, and drafts.
There is a simple formula shown below (I used Ace as my model) which is a little more complicated (than just measuring around his body) but results are found to be a more accurate estimate of your horse’s body weight.
First, measure your horse’s heart girth in inches. This is from the base of the withers (a few inches behind the front legs) around the body and up the other side to meet the tape at the top of the withers as shown. Ace measures 75 inches.
Second, measure your horse’s body length in inches. Measure the distance between the point of the shoulder and the point of the hip. Ace’s body length is 55 inches.
Third, calculate the weight:
- Multiply the heart girth by the heart girth 75 x 75 = 5625
- Multiply the result by the body length 5625 x 55 = 309375
- Divide the result by 300 then add 50 309375/300= 1031 + 50 = 1081
Ace’s estimated body weight is 1081 pounds.
This article was written by Susan Boyd and edited by Zachary Franklin, DVM