While breeders continue to measure these traits using visual assessment, there is an increasing tendency to use objective measurements where practical. Objective measurements are less prone to operator bias, are more repeatable from one occasion to the next and show a greater and better defined range of values. Breeders can measure traits such as fleece and bodyweight but visual measurements are subject to bias. Objectively measured traits are generally associated with better genetic gains. All these attributes mean objectively measured traits are generally associated with better genetic gains than their visually assessed equivalents.
Some measurements are too expensive for breeders to contemplate such as staple strength.
CV measurements are now routinely provided at no extra charge with fibre diameter measurements. There is now an Australian standard for measurement of wool and fleece properties which includes some aspects applicable to breeders. Just as careful sampling and measurement procedures are required, careful recording is a vital part of the chain. Misreading of tag numbers is surprisingly common, but can be reduced by checking tags off a prepared list. Some people are prone to confuse figures and are best allocated to other tasks.