[Jacob-list] importations

[Jacobflock at aol.com]

This is an offering of some references which may help  illuminate some of 
the comments that Neal has offered and may  represent some basic Jacob 
information for some new "listers":
 
1. Oryx magazine (12/70) expressed concern that the "original" Park sheep,  
recently popularized by the Jacob Sheep Society, would be improved and  
standardized in an effort to conserve the breed; the primitive characteristics  
would be lost by conformance to a breed standard and "marketing 
opportunity"  improvements.  The ARK (6/74) noted that the Jacob of 1974 was about  40% 
larger than the 1969 version  and no longer "looked" like its  primitive 
ancestor.
 
2. The Jacobs imported to Canada(e.g., Turner) could have been primitive  
types or improved, it is not clear on what basis the flock was originally  
formed.  On the other hand, those imported by Hescock were selected as  
"improved" type as he had a "commercial" purpose in mind ("Importing woes were  
worth it",Sheep Product, 7/84).  There is some genetic evidence to suggest  
that, when Hescock moved his flock to Turner's place for quarantine, some  
breeding between the flocks occurred based on the TS gene (TAMU, 2000, 2009;  
NYU, 2008).
 
3. The "standardization" of the Jacob in North America can be laid to the  
small gene pool, often referred to as a genetic bottleneck and flock  
structure (few rams).  The study by the USDA-NGP (2/04) covered over  2,000 births 
and indicated the rapidly increasing percent of inbred  animals from 1983 
to 1994 and a more positive trend of reduced  inbreeding from 1995 to 2002.  
The 1983-1994 period was a period that  contributed greatly to "fixing" the 
Jacob=American traits but  also marked a period of a relatively high 
incidence of congenital  problems in the breed.
 
4. The appellation used so often by Jacob breeders...  "a unique  breed".. 
finally was verified in 6/2005 when the USDA-NGP did the mDNA based  study 
to look at breed distances.  The Jacob did turn out to be unique  and the 
"Spanish four-horn" was not closely related to the Spanish  "churro".
 
I hope the above with the sourced information will be helpful in  
understanding the Jacob breed ... of course there is more.
 
Fred Horak
St. Jude's Farm
1165 E. Lucas Rd.
Lucas, TX 75002
972-727-0900
 
 
In a message dated 9/20/2009 2:12:28 P.M. Central Daylight Time,  
nlgrose at yadtel.net writes:

Everything has a starting point. What we call  purebred is a collection of 
animals of similar traits that have been isolated,  inbred, and reselected 
for type. It might have been 50 years ago, or 150  years ago, or 1500 years 
ago. Other than Soay, which is not strictly a  domestic breed, the only thing 
that would fit the later standard would be  Merino and English Longwool. 
(Neither exists in a form that they had 1500  years ago).  
 
You don't say wither the sheep you saw had  mixed Jacob ancestry. I have 
seen plenty of 3/4  Jacob lambs. There is always something askew with these 
sheep: the fleece is  too heavy, early greying, the bone is too round, the 
color pattern is  funky, ...something. There is no Jacob gene. Jacob-ness comes 
from a  combination of many genes and many traits. It is certainly  
possible that Jacob Crossbreds, bred back to each other might produce a lamb  with 
a good degree of Jacob type, but there would be a significant amount of  
off-type character that would show up without careful reselection. That  
doesn't mean that I think that we should allow these animals into a  registry...we 
have already done the hard work of multi-generation  standardization for 
type for an animal that mostly agrees to what we mostly  agree on. With lack 
of a sample of DNA from a representative group of  sheep from 1880, that is 
the best we can do.
 
Neal Grose 
North  Carolina


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