[Jacob-list] Primitive Traits/HyBrid Vigour/Where Are We Now?

[ranchrat at telusplanet.net]

Heel low:

Fred Horak <Jacobflock at aol.com> wrote:

> So what we got in North America is the "unimproved" type both black 
> and white and "lilac" and a more "improved" type that met with the 
> JSS breed standard and as described by Todd Hescock.  What is known 
> today is the British Jacob has been improved largely with the Dorset 
> Horn but always breeding back to Jacobs to improve the Jacob.  (See 
> also the article in the Spring JSS Journal which reflects the typical 
> expression of pink nose, heavily streaked horns admixture; easy to 
> put into the breed but is still being expressed thirty years later.)


PRIMITIVE TRAITS
I guess I get hung up on the fact that the Jacob is suppose to be a “primitive” 
domestic breed.  To understand primitive traits, am I incorrect to assume that 
the more primitive the characteristic, the more likely it is to have a dominant 
affect upon the breed—what ultimately looks like a Jacob?  I say this because 
my thinking is that when man develops a domestic breed, he does so through 
careful selection for traits he so feels are desirable.  We are able to pull 
recessive traits forward to be expressed physically through our manipulation of 
breeding selections.  So much so that we have them become part of the makeup we 
feel we want in a breed of animals and select for this until the trait breeds 
true.  For example, the homozygous “b” brown coloration is desirable in a Short 
Hair Pointer (a canine whose standard allows for brown nose pigment) but 
undesirable (not listed in the standard at least for a dog that must have a 
black nose irrespective the color of the dog) for the Australian Cattle Dog or 
the Australian Stumpy Tail Cattle Dog.

We may take a St. Bernard, a poodle, an ACD, and a Labrador Retriever and leave 
these dogs to breed as an isolated colony
after generations of breeding, I am 
told the progeny will all begin to take on the physical appearance of one of 
the most primitive dogs, the Greyhound.  If we took a Suffolk, a Romanov, a 
Jacob, and a Dorper and left them to breed without human intervention
what 
would the resulting progeny look like after several generations?  I ask this 
because of Fred’s comments that Jacobs’ have retained mutations from the 
Mouflon:

Fred Horak <Jacobflock at aol.com> wrote:

> The Mouflon question and considerations.  The Jacob is a Mouflon type.  Most 
> "modern breeds" are Mouflon mutations and crossbreedings.  Mutations from 
> Mouflon to Jacob include (1) a dominant black gene, (2) piebald, (3) face 
> patches and spotted legs, (4) badger face (5) multiple horns, (6) lilac/grey.

Is there any validation in concluding that the more primitive the trait, the 
more Jacob it is and therefore more desirable in our flocks in a conservational 
sense?  Does the Jacob require careful nurturing to keep it pure or are we able 
to barge ahead without concern, buying up animals from the auction marts who 
have the phenotype of Jacobs, breed and progeny prove their Jacobness, simply 
because we are conserving a primitive breed?  Basically, are the Jacob 
primitive traits strong enough to withstand crossbreeding?  Are they retained, 
even the recessive traits, for our retrieval?  

What are we losing or gaining through the mixing of Jacobs with modern 
genetics?  If pink noses, larger body size and denser wool are all modern day 
sheep traits, why have they stuck so well into our Jacob gene pools if the 
Jacob is suppose to be a primitive breed.  I would think the Jacob is our 
foundation of building blocks and should not be so easily thinned by the 
addition of our much more manipulated modern breeds?


HYBRID VIGOUR:
If one takes a Romanov and breeds it to a Suffolk, you will get an offspring 
that expresses hybrid vigour
the progeny is more vigours than either of its 
parents
does better so to speak.  Would it be plausible to believe that if one 
took what one figured to be a pure Jacob and bred it to a Jacob you had 
questions about, if the offspring exhibited hybrid vigour, would that be one of 
the clues to affirm what you suspected, the Jacob you questioned was not as 
much a Jacob as you had hoped?  I realize we are suppose to breed animals that 
are better than its parents, but would huge leaps say in size or vitality be a 
measure of pureness we could use to assess a questionable Jacob?  Would 
something similar to hybrid vigour come from a large outcrossing within the 
Jacob gene pool from very unrelated sheep?  Is this a tool we may put into our 
handi dandi “is it a Jacob” tool box?


JACOB BREED-WHERE IS IT AT IN NA?
Would it be plausible to conclude that the modern day Jacob (the North American 
Jacob) is actually at the stage where one might be able to call this nearing 
the end of the “development” era for the breed?  As I understand, the formation 
of a domestic breed is considered to be near completion when it breeds true to 
itself, replicates itself in both pheno and geno-type to an acceptable breed 
standard.  From some of the pictures and visits that I have been able to make 
of US and Canadian flocks, we are able to observe that some are replicating 
a “type” or “look” that can be linked back to the originating breeder.   
Like “peas in a pod” some breeders’ animals just look like each other, so one 
may simply look at the Jacob and say that this is a “such & such” breeding. 

The Australian Stumpy Tail Cattle Dog (ASTCD or Stumpy) had to go through a 
redevelopment in Australia to recover the breed from near extinction of the 
registerable stock.  There was only one kennel raising registered Stumpies and 
this family kennel had been refusing to sell breeding stock to outsiders.  The 
Australians opened up the registering system to a classification board (A, B, & 
C ratings depending on how much the phenotype resembled the breed standard) and 
slowly collectively bred “up” the numbers using genetics from the still 
numerous unregistered animals, culling heavily for things like tan markings 
(shows afflation to the Australian Cattle Dog, a close cousin who is usually 
agouti a“t” and not agouti A”s” like the Stumpy) and long tails (as recent as 
1945, long tailed pups in a single litter were registered as ACDs while the 
stump tails were registered as ASTCDs).  Today the breed is again safe and even 
takes Best in all breed Shows in Australia. 

Jacob numbers seem to be healthy in the US, but here in Canada with only 130 
(plus my 5 recent lambs) ever Canadian registered, I would not consider the 
breed to be safely out of the danger zone, even though the Jacob is no longer 
listed as a “rare breed.”  I suppose our “rare” breed status/classification has 
been dropped simply because the Jacob is so very numerous across the 
Atlantic.   I figure the powers that be do not understand the concept that 
30,000+ Jacobs are of the mostly “improved” variety whereas mine are 
basically “unimproved” or North American Jacobs.  There are Canadian Jacob 
flocks that are not being registered and there are the odd times where you will 
see Jacobs being sold at the auction marts.  All the pointers and tips to help 
one decide if the animals presented are potentially “Jacob-like” are greatly 
appreciated in helping to keep the gene pool healthy.  The Jacobs from the 
Winnipeg zoo, some have been lost to us, but potentially their descendants are 
still out there, appearing here and there for us to recover.  

Understanding things that make the Jacob unique compared to other sheep breeds 
helps educate one so that if one so chooses to recover “mixed” genetics, you 
know what “signs” you are watching for.   I always felt that unless you were 
cross breeding and examining the offspring that resulted, it was rather 
difficult to have any integrity in being able to “breed type” an animal.

Doggone, 

Tara 
-- 
     ____(\                Tara Lee Higgins                  /)____ 
    (_____~>        Rat Ranch - An ACD is for LIFE          <~_____) 
   ( ``  ``          ranchrat at telusplanet.net                ``  `` ) 
    \                       Alberta Canada                         / 
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