Charting Herd Improvement

The slides below are from our 2019 EPD testing results. They provide a glimpse of how EPD’s can be used for mating selection and tracking the overall herd improvement.

Stargazer has incorporated the use of EPD's in our breeding program for over 15 years.

These graphs chart our progress for our entire herd of about 50 Huacaya alpacas. Our herd is about 50% male & 50% female and range in age from 1 year to over 20 years old. Stargazer's protocol is to test every animal in our herd each year from 1 to 10 years old. The Green Line in the chart represents the neutral value for that trait. It is calculated from about 40,000 huacayas that were submitted for testing nationwide.

Each of the red squares represents an animal in our herd and also corresponds with the year it was born along with the EPD trait value. Reducing fiber diameter is a common goal. Unfortunately, what's not well understood by most breeders is the negative effect it can have on fleece weight production.

It wasn't until we started using EPD's that we were able to properly identify pairings that would reduce fiber diameter and increase fleece weight. EPD reports have shown that improving fleece weight is 33% more difficult than improving fiber diameter.

When breeding for finer fleece, fleece weight predictions should always be taken into account. Red squares above the green line indicate that alpaca will increase fleece weight in a mating. Standard Deviation is used to measure the uniformity of fibers. Improving uniformity is as important as AFD.

Improving SD in alpacas has proven to more highly heritable than originally thought. (52%... same as AFD)
Spin Fineness describes the loss or gain of relative AFD due to the impact of SD. (SD of less than 24% improves the relative fineness of the clip.)

Improving SD provides the user with a stronger fiber that acts and feels much finer. Fibers over 30 micron also speak to uniformity.

These are fibers that are generally referred to as guard hair. The purpose of tracking this trait is to track progress on how fine the coarsest fibers are. Medulation will affect the commercial value of fiber due to the effect it has on color dying.

Medulation can be reduced by proper breeding and also by reducing fiber diameter. Curvature is a mechanical measurement of the crimp or crinkle of the fiber. Curvature helps define resistance to compression. Higher curve will relate to fewer fibers needed to spin a certain gauge of yarn and will also increase the memory of the yarn. Measurement of staple length is done in a relaxed state. (unstretched)

High curvature will negatively or adversly affect staple measurement as compared to low curve.

Feel free to contact us if you have any questions. Holding your mouse over the slides should pause the sequence. Use arrows to navigate forward or back.

 

On December 20, 2020   /   Alpaca EPD Posts, Alpaca Fiber, Alpaca Husbandy Breeding & Genetics   /   Leave a comment