[Jacob-list] question on horns

[Neal and Louise Grose]

Sheep seem to be more complicated than cattle on horns. In Polled Dorsets (developed at good ol' NCSU by Dr. Goode, who taught both my Father and me in Ag Science) the polled gene is recessive, which allowed it to be bred into the population rather quickly since there were no pesky recessive undesirable traits (horns) to stay hidden in the population. Crossing Polled Dorsets to polled Finnsheep can produce horns on rare occasions.

There is a New Zealand "rug wool" sheep breed that was developed from the (polled) Romney breed. Something about the breeding for coarser wool inadvertently caused increased horn development.

The "hornless" (as opposed to polled) Jacobs that we have tracked are smooth headed with no scurs or poll indentations. These are hornless ONLY in the ewes. The rams in these families remain strongly horned. This is the same expression in traits that we see in Shetlands. It seems to be both sex-linked and recessive.

My guess is that the SUED trait relates to a split in the cranium plates, and the splitting of horn buds are secondary to this. This might account for Mary Ellen's ram lamb that is polycerate AND two horned. Hey MEH, care to put the joker in the freezer just so that we can see what his skull looks like?

Neal Grose  
  ----- Original Message ----- 
  From: Linda 
  To: Mary Hansson ; Jacobflock at aol.com ; Jacob-list at jacobsheep.com 
  Sent: Thursday, April 28, 2005 7:11 PM
  Subject: Re: [Jacob-list] question on horns


  Was it a ewe or ram lamb?  Isn't polled dominant over horned?  I am not sure how it works over hornless. Could the lamb have been phenotype polled, but also carrying a polycerate gene either as horned or hornless?


  Linda


  On Thu, 28 Apr 2005 10:18:48 -0700 (PDT), Mary Hansson wrote:
  > Fred,
  >
  > I have observed a Cotswold/Jacob cross POLLED animal with a grade 4
  > split......shocked both me and the breeder.  Just another animal
  > that messes with our great theories.
  >
  > BTW:  The little 4-horned ram lamb that was born a couple months
  > back to parents that were/are both 2-horned (at least on visible
  > CLOSE inspection) is one of the prettiest ones in the flock of
  > lambs---markings, horns, fleece, everything.......  Fleece isn't as
  > good (fine) as Nutsy's fleece was, but it is nice.
  >
  > MEH
  >
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