[Jacob-list] Inbreeding, etc.

[Mary Spahr]

To answer Linda's question about choosing a Jacob ram with nicely spaced horns vs. a fused horned one:  I would choose the ram with the nicely spaced horns.  If I had to choose between a ram with a coarse fleece or one with a fleece that had a softer handle, I would choose the one with the softer handle.  A weaver might decide to choose the coarser one.
We do all have our preferences, and the majority of us practice selection in one form or another.  I believe that both registries allow sufficient room for the breeder to exercise his/her own individual likes and dislikes.
In 1988, Jacob sheep were difficult to locate and the selection was very narrow.  Through the years I have seen more and more Jacobs available and the quality of the sheep has steadily improved.  Not all registry traits can be labeled as "superficial."  I really do not care how many spots our sheep have as long as they fall within the 15%- 85% range.  I do not care if they have one facial marking or three.  I do not care if they have leg spots or not, a black muzzle or black pigment, nor do I care if some of our ewes have fused horns or a #2 split eyelid as long as they are good mothers and can lamb unassisted.  That does not mean that I don't still get excited if we have some born that compare to my mental image of the "picture perfect" Jacob.  I have learned that the others are just as valuable for producing and raising lambs that possess the traits Jacobs are valued for.
I do care if a 2-horned ram has narrow horns and a 4-horned ram has fused horns or excessively forward horns.  We do not have the time or inclination to saw off the horns of a two-horned ram when they start pressing into the side of his face.  Been there - done that.  We do not like fused-horned rams.  It has been our experience that they do pass that trait on to offspring and prefer to keep more genetic diversity in the ewe flock, not culling fused horned ewes for that reason.  Our first Jacob ram had very forward horns and eventually found it difficult to get his head lowered enough to eat.  We prefer not to take chances using a ram like that again as he did pass it on in some offspring.  I would not belong to nor advocate a registry that demanded "perfection."  Ours does not. 
I am more concerned with the notion that inbreeding has no effect on the flock.  What about elf-toes, swayback, parrot-mouth, bulldog mouth, possibly OCD, reduced hardiness, and perhaps other traits linked with inbreeding/linebreeding?
I do not know the exact heritability of these traits but prefer not to take chances.  Even if those who practice inbreeding have been lucky so far, it seems like an unnecessary risk to take, especially if a large flock is involved.

Mary Spahr  
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