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close this book Animal traction
close this folder 2. Draft animal selection
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View the document Method for determining size of the hitch
View the document Determining weights of animals
View the document Selection of individual draft animals
View the document Conformation
View the document Temperament

Determining weights of animals

To determine an animal's weight, first measure the length of the animal from point of shoulder to point of rump (A-B) and the circumference of its torso at point of heart (C) with a tape or rope. (See the drawing on page 20.) When taking the torso or girth measurement, observe these rules:

• Measure in the morning before the animal drinks. Don't give it hay the night before.

• Have the animal stand squarely with its head in a normal position.

• Pull the tape snugly around the torso, at the smallest circumference behind the shoulders.

Table 4-Power of Bulls (in yoke)

Next, follow these formulas:

For bovine animals

Substitute measurements A-B (length) and C (circumference of torso at point of heart, or girth) into this formula:

(girth x girth x length)/300 = weight

For this formula, measurements must be taken in inches. If a metric tape or rope/rule is used to measure the animal, centimeters must be converted to inches before the formula can be used. One inch = 2.54 cm.


Girth of bull measures 152 cm, length measures 135 cm.

152/2.54 = 60 inches (girth)

135/2.54 = 53 inches (length)

(60 x 60 x 53)/300 = 636 lbs

Since one kg = 2.2 lbs, the weight of the animal in kg is obtained by dividing 2.2 into the answer above (636 lbs).

636/2.2 = 289 kg

The bull weighs 636 lbs or 289 kg.

An alternate method for estimating the weight of a steer (castrated bull):

Live weight • 1.04 [27.5758 x heart girth) -1.04967]

For equine animals

Substitute measurements A-B (length) and C (girth) into this formula:

(girth x girth x length)/300 + 50 lbs = weight

Measurements must be taken in inches, or converted into inches, before the formula is used.


Donkey's girth measures 37 inches, donkey's length measures 35 inches.

(37 x 37 x 35)/300 + 50 = weight of donkey

160 + 50 = 210 lbs

If the animal's weight is to be expressed in kg,

210/2.2 = 95 kg

The donkey weighs 210 lbs or 95 kg.