Café Au Lait
Paul Abbé - 1978 - " Dans cet effectif, la grande majorité des sujets sont noirs ou bruns foncés; 13% sont blancs et quelques individus "café au lait"
I wanted to revisit this quote as there is considerably more information to look at in this unassuming text, previously discussed HERE in relation to white spotting.
As a descriptive of colour "café au lait" is well observed but it isn't a technical term nor is it a recognised genetic term, unsurprising as at the time it was written, the genetics in the Ouessant sheep were considerably less well understood but as is often the case it is the accuracy of the description that helps with the interpretation.
As a descriptive of colour "café au lait" is well observed but it isn't a technical term nor is it a recognised genetic term, unsurprising as at the time it was written, the genetics in the Ouessant sheep were considerably less well understood but as is often the case it is the accuracy of the description that helps with the interpretation.
Café Noir
A cup of coffee, its colour and description of that colour comes with an intrinsic understanding. One is black based the other white.
The interpretation in genetic terms corresponds very well. The appearance of highly pigmented lambs whose basic genotype is white ( Agouti white and tan) is documented and explainable but the reference to café au lait goes further in clarifying the basis of that colour and its association with white.
The "stronger" the colouration the closer to black it becomes - café noir. In breeding experiments it has been possible to demonstrate this as a genotype. In using some of the most extreme colouration at the furthest end of the coffee scale it has been possible to produce eumelanic ( black ) lambs.
The sheep whose colour expression is outside the breed standard have demonstrated this mechanism in action. The white spotting pattern in this lamb confirms its genotype as an expression of Agouti, the darker pigment in the lamb confirmation of the origin of the darker expression of a "café noir" coloured ewe. Expression of white spotting is variable depending on genotype as is the appearance of a darker (eumelanic ) lambs. However proving the mechanism and expression of this colouration isn't sufficient to confirm its identity as "Ouessant".
In order to understand colour expression in the Ouessant and in doing so confirm breed identity it is necessary to go further and look at the pattern of expression that is documented throughout history and is echoed in Paul Abbés choice of words. More forensics coming soon.
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