[Jacob-list] Question......

[Jacobflock at aol.com]

Dear Cindy and listers; 
I'm not sure that a measured response to Cindy's questions will  
significantly add to the storehouse of knowledge but here is an offering. Keep  in 
mind that my references are in the public arena and references to  our flock is 
only one of hundreds of flocks.
(a) There are as many reasons for having Jacobs as there are Jacob  owners. 
 There are some that have a small flock of say 10 ewes and a couple  of 
rams because they enjoy looking at them and have some lawn to mow.   There are 
others who think they are rare and rarity creates economic  value.  There 
are some who have a commitment to conservation breeding in a  more complete 
sense and pursue that course.  These are examples of  reasons, not a complete 
list nor exclusive by reason.  Reasons for  having Jacobs can be mixed and 
often are not exclusive.  We try to be  conservators; our flock has about 30 
rams, 120 ewes and about a third of our  flock is sequestered for genetic 
studies.
(b) Just as beauty is in the eye of the beholder; we often use the term  
"primitive" through the eye of the beholder even though it has become a  
defined term, somewhat complex, with a genetic component.  Initially, the  term 
primitive becomes somewhat somewhat defined and popular with respect  to five 
sheep breeds (including the Piebald horned sheep) in the early  1900's 
(Elwes, 1913, the criteria previously posted on the list).  The  concern for 
conserving what is recently popularized as the Jacob in 1969 results  in both a 
"primitive" Jacob and a heavier, "improved" Jacob (Ark,1974).   The RBST 
becomes involved with the definition of the Jacob and after it is  
popularized, is "classified" as a "hill breed" and a "ewe breed".  The  "primitive" 
breeds remaining in England are defined as: Soay, North Ronaldsday,  Shetland, 
Hebridean, Manx Loughton and Hill; each markedly different in the  
relationship between weight AND the inter ishial tuber diameter compared to all  
other breeds and its "low management" requirements.  The UN, in its  worldwide 
animal agriculture conservation paper has also referred  to the easy 
lambing/tuber ishii criteria.  The Jacob in Great Britain  weight/tuber-ishi ratio, 
on average, did not meet the "primitive"  criteria.  But some individual 
sheep may have met the definition.   Primitive is not, per se, good or bad.  In 
one sense it is good for easy  lambing and low management, in another sense 
it is bad for carcass weight, lamb  growth, prolificacy and fleece.  
(c) At the flock level, I did a study of Jacob (n=71) birthing and  
dystocia (one characteristic of "primitive") was done in 1999 and  again in 2000: 
average weight 42.91kg, sd 3.18; tuber ishi 41.29, sd  2.95mm.  Only 28 of 71 
ewes fell into the definition of primitive.   For over 100 lambs there was 
no dystocia; but keep in mind the  weight/tuber ishii ration is at the 
margins.
(d) The "ideal" Jacob specimen is basically determined by the breed  
association (bylaws) who register sheep as pure bred and suitable for  breeding 
purposes. The breed association and breeder move the breed through  the rocks 
of Charybdis.  Individual breeders breed to meet their flock  objectives.  
Breed fad, not a laudable goal, is in fact an  objective; blue eyes, maybe 
throat mane, etc.   What must not be  overlooked is the forest; other breed 
phenotypic traits that are not as  obvious as its dominant black, recessive 
piebald, polycerate but  adaptability and performance.  One can "preserve" the 
Jacob by  cryo-preservation at a moment in time. "Conservation" implies 
carrying the Jacob  traits through a changing environment and the fine line 
between  genetic diversity and inbreeding; e.g., (Jacob breed status (n=2,400) 
by  the USDA-NAGP 2004).  If one breeds the "ideal" ram to ten ewes (ceteris 
 paribus), virtually nothing is added to genetic diversity (effective 
population  of 4) ... but two "good" rams over 10 ewes doubles the effective 
population  (say 7).  (ALBC, Conservation Breeding Handbook).  One really has to 
 think through some complex issues but there is help out there ... at least 
a 100  year old warehouse of knowledge!
Regards,  
Fred Horak
St. Jude's Farm
1165 E. Lucas Rd.
Lucas, TX 75002
 
 
In a message dated 9/16/2010 10:12:44 P.M. Central Daylight Time,  
im-rapunzil at hotmail.com writes:

Now I'm  asking this question because I'm new to Jacobs - NOT trying to be 
a  smartass.

As I understand it, the purpose of breeding Jacobs  isn't for the show 
ring; rather breed preservation.  My reason for  getting into Jacobs is because 
its a Heritage breed and I want to  help it flourish.

We hold our Jacob sheep dear for their  primitiveness.  So my question is:  
What are we breeding  Jacobs for if not a most ideal specimen?

Are those "Other" sheep  breeders not striving for the ideal applicable to 
their breeds purpose  i.e. meat, milk, wool?

And how would anyone know what an "ideal"  Jacob specimen is supposed to 
be?  Let's consider its a  primitive breed established well before our 
time......  What  exactly is this primitive breed supposed to be?  Who is the  
Authority of what aspects of primitiveness is good, and what is  bad?

Does someone have "The Ancient Handbook of Jacob Breeding"  they'd like to 
share?  

I know of some folks on here  that have both Jacob and the "other" sheep.  
I'd like to read  the take they have on this.  Actually, I'm anxious to hear 
EVERYONES take  on it!

Looking forward to your  replies.

Cindy
Stone Hollow Farm

You live by writing your poems on a  farm
and call that  farming.













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