[Jacob-list] tail lengths - from David Kinsman

[gordon johnston]

Hi All
I asked David Kinsman for more details on the tail vertebra counting, for which he was asking for your help.  ( BTW Hebrideans, for those of you not familiar with the breed, are a British rare breed, mainly 2 or 4 horned, all black and genetically largely black recessive - but with a significant degree of black dominant to suggest some intermixing with Jacob.  A small and very hardy breed )
This is David's reply : 

My experience with adult Hebrideans suggests that one
needs a sheep which is not in good condition, in order to be able to
feel the individual caudal vertebrae. I found on ewes that late
June/July was the best time, after they had been pouring themselves into
their lambs for 2-3 months and so if one said 3 months after lambing
this would be a good guide. Evenso, I could never feel the smallest
vertebrae at the distal end of the tail. I could rarely count more than
12 out of the expected 15 vertebrae, but even this is useful data.
Why is the information of interest to me? Several lines of evidence
(historical, wool genetics, scrapie genetics, etc) indicate that the
Hebridean sheep almost certainly contains a significant amount of Jacob
in its makeup. The two breeds first met as parkland sheep in England in
the late 19th century and became, by design or accident, crossbred. The
Hebridean is a northern short-tailed sheep (<15 caudal vertebrae),
whereas the Jacob is a long-tailed (>20 caudal vertebrae) breed But
long-tailed breeds may have 20-30 vertebrae, although the number is
fairly breed specific. Some new research suggests that when short & long
tailed sheep are crossed, there may be evidence of such crossing in the
tails of the progeny. Indeed, of all the northern short-tailed breeds in
Britain, the Hebridean has the longest & woolliest tail. I am exploring
whether the nature of Hebridean tails is yet another indicator of Jacob
input to the breed. It would thus be helpful to know how many caudal
vertebrae are in the Jacob, as one end member of the cross breeding
continuum.
David Kinsman
dph at ceh.ac.uk



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