[Jacob-list] lilac

[Neal and Louise Grose]

As a dairy farmer, I am struck by the parallels between lilac and Red and White Holsteins. U.S. Holsteins have registrations and a breed association going back to around 1880. From then until about 1975, color standards were quite rigorous. Red and Whites were not allowed to be registered. Prestigious breeders adamantly denied EVER having such crossbred looking animals...and often killed the red calves at birth or gave them away after extracting a promise that no one would find out where they came from. During the ' 70s, an active export market to countries that offered a premium for red and whites suddenly made it a pretty good idea to accept R&W Holsteins along with the Black and Whites for registrations. During the 1970s, efforts to developed red coloration in herds were quite successful. For one hundred years prior to this, there were NO registered R&W Holsteins. So, for one hundred years, the gene for red stayed submerged in the gene pool. Red coloration in Holsteins is a simple recessive to black. [Does this sound familiar? For the record, crosses to Ayrshires do not come out productive enough to make it worthwhile, so this was not a consideration.]

What we know of the history of Jacob sheep is a history of segregation into a number of isolated breeding groups. I remember a conversation with Edd Bissell in which he related that one of the early flocks of American Jacob sheep were lilac and maintained as an inbred group because the breeder did not like the confirmation of the outcrosses that he tried...not necessarily because he liked lilac. Isolation and inbreeding have been key to the development of abnormalities due to recessive genes. In many ways, the Jacob sheep that we have now are the most homogenous and the most "purebred" that they have ever been due to intermingling and standardization through the breed standards. This outcrossing tends to make animals more 'average'. Interestingly, there were probably more Jacob sheep imported into the North America than there were Holstein cattle. This does not mean that there is more genetic diversity in Jacobs than in Holsteins. Holstein breeders have practiced breeding programs that utilized alternately inbreeding and then outcrossing of bloodlines, thereby providing a chance to recombine the DNA that was available. This together with the large numbers of animals in the Holstein breed gives them the most genetic diversity of the dairy breeds. There is MORE genetic diversity in Holsteins now than in 1900.

For all practical purposes, all breeds start out as crossbreeds. They are reselected over time for genetic conformity. The key is to see WHEN a breed is first designated as purebred. Jacob sheep are no different, even though the breed origin predates most modern breeds. [I do not know that anyone paid a lot of attention to distinct breeds before 1800, and most breeds date to the mid-1800s.]  Then too, at the time of the origin of these breeds, fences served primarily to keep the beasts OUT of the garden. Woven wire and multiple stranded high tensile fences were far in the future. The Jacob sheep may well have started as simply the piebald variant of the basic Viking sheep. There has been some debate about northern European or Mediterranean origin of Jacobs, my own guess is that it is most likely that they are 'Viking' flocks that had similar looking "collected" rams added to them from all that traveling and colonizing that the British did. Jacob sheep were a collector's item in which oddity and diversity were prized and preserved. 

All of this is to say that the lilac gene is as intrinsic to the Jacob breed as is the red color gene is to Holstein. Color is a superficial trait, and is governed by a handful of genes. [Similar comments can be made about recessive traits that affect horn development. They may not be desirable, but these traits are impossible to use to differentiate authentic animals with a high degree of certainty,] If we were to suddenly get rich and sequence the genome, "lilac" would be a bare blip in the gene pool difference between Jacob and the other breeds. If you really want to see a difference, look at the pelvic structure of American Jacobs, the flat and dense bone, unique fleece characteristics, body confirmation...

Neal Grose 
North Carolina

PS: I just have to add, after mentioning that I am a dairy farmer, that the recent price increase in milk IN NO WAY reflects the farm price of milk. Milk has gone UP 30-40 cents here...and the farm price we get has gone DOWN 30% in the last year!







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