Thursday, March 25, 2010
And now for something completely different
Another breeding group we have, which I briefly described earlier, is the self-colored light phase, aka SCLP or self-light. Before I obtained the two that are still know to be alive in North America, I was working toward producing them on my own.
One way to do this is to assure that each lamb has one copy of both recessive genes, and this is done by mating a self-black with a light-wild (presuming that the black does NOT have a hidden copy of light, and that the wild does NOT have a hidden copy of self). I did this with a number of pairings for the 2008 lambing season, and obtained 4 ewes and 2 rams with the genotype A+/Aa, BB/Bb. (Some were also homozygous for white spotting as well, but let's keep this simple for now).
When I unexpectedly obtained the self-light ewe Blue Mountain Cocoa last summer, my best bet for a sire was to use my "half-way" SCLP ram, Woodland Creek Sequoyah, with a genotype as described above (and Ss/Ss, so a small white poll spot too, just in case you wondered.)
So here is Cocoa, the SCLP.
Blue Mountain Cocoa '08
and the sire,
Woodland Creek Sequoyah
So what were the possibilities and odds? With the dam genotype of Aa/Aa, Bb/Bb, she had to contribute Aa and Bb, both recessive. The sire, however, could have contributed A+, Aa and BB or Bb. So there was an equal 25% chance of any one of the four basic coat patterns - dark-wild, light-wild, dark-self, or light-self (shown in the order of more to less common). Drum roll... the result was...
Blue Mountain Cocoa and her 2010 ram lamb
I had observed the breeding of Cocoa and knew that if successful she should be due today (+/- a day or two), and she was acting funny yesterday evening. When I searched for her at 4 AM, I found her with this little ram lamb. For some reason I find the sight of a solid black lamb with a "chocolate" ewe to be very odd. So this little ram (not yet named) will has a known genotype - he has to be Aa/Aa, BB/Bb, SS/Ss (the last because the sire Seqoyah has a small white poll spot, but the new ram lamb does not). He would have pretty decent odds for use in a breeding program to produce more SCLP Soays.
Not to make too much of it, but I am pretty sure this is the first birth in North America of a self-black lamb to a self-light Soay!