Its methods will help to steadily improve your whole flock. The first step in establishing a breeding program is to decide what kind of changes need to be made to the existing flock. There is no use in making rapid change if it is in the wrong direction. Selecting the right animals Variation Most traits of interest to sheep breeders have a 'normal' distribution. A familiar example is the histogram provided by fleece testing labs to show fibre diameter distribution.
Many fibres have a diameter that is fairly close to the average.
The number of fibres in each micron category drops rapidly moving further from the average. Only a few fibres of the finest or broadest microns are present in any sample. Similarly, there will be many sheep in an unselected flock whose fleece weight is fairly close to the average. Weighing scales attached to a datalogger that aids in recording fleece weights. Traits with a large CV vary widely around the average.