[Jacob-list] importations

[fourhornfarm]

Very interesting Neal and Fred. What information do you have on the changes in Jacob fleeces over the years?
  ----- Original Message ----- 
  From: Jacobflock at aol.com 
  To: nlgrose at yadtel.net ; jacob-list at jacobsheep.com 
  Sent: Wednesday, September 23, 2009 11:06 PM
  Subject: Re: [Jacob-list] importations


  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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