Jen Pietsch
Orcas Island, WA

I love spending time outdoors, gardening, running and raising my fleeced friends!
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Tuesday, February 19, 2008

postheadericon Breeding Notes: Part I

The last couple of weeks have been filled with cleaning house and packing to move. Through it all, in the back of my mind has been a constant concern about and delight for the prospect of selecting potential breedings for the upcoming season.

I have been reading and asking questions from experienced breeders, soaking in everything I can find about genetic selection methods. Keep your eyes peeled - over the next couple of posts I will fill you in on what I have learned. Today, however, I will discuss what is known as “line breeding/in-breeding” versus “out-breeding”.

Line-Breeding vs. In-breeding

“It’s line-breeding if it works… it’s in-breeding if it doesn’t.”

Strictly speaking, line-breeding is any mating in which the mated animals have a common ancestor. When first-degree (mother/son, sister/brother, etc...) pairings occur, it is often called in-breeding. Line-breeding implies more distant relationships between the pair.

The reason for line-breeding is to produce offspring that are more genetically uniform with the goal of accentuating superior traits. With line-breeding, good traits hopefully become more consistent, although it can also magnify less desirable traits by making them more consistently prevalent as well.

In-breeding, on the other hand, tends to bring recessive genes to the surface by forcing them to pair with one another. With either in-breeding or line-breeding, the genetic pool becomes drastically smaller and the general health and fitness level of the off spring may suffer. To sum it up one can use line-breeding to achieve greater predictability in their breeding program but not without risks.


Out-breeding is breeding of animals that don’t have common ancestors. The predictability of outcome of this method of breeding is decreased. Out-breeding can hide recessive genes in a way that they can’t be expressed. Inferior genes or traits can therefore be more widespread than the outward appearance would have you think in advance.

So What Is One to Do?

I see the merits of both and will seek to appropriately combine both line- and out-breeding. Much of our herd has great genes that I would hate to not ignore. The fear of the consequences of a breeding gone wrong seems to be a gamble. Therefore, in order to make the gamble pay off, I will try to ensure the positive traits that I seek to compliment from our Dams are ones that I can be reasonably assured will be passed down.

To increase the odds of achieving this goal, I will also research the off spring on the ground from the selected sires. Have the traits I want to pass on and see in my cria been passed down previously? Coupling this ‘seeing-is-believing’ approach with a healthy dose of caution about line-breeding should ensure an improvement on our herd over time.