IVO explained......AaAa BBB_ SsSs E+E+

....... or colour inheritance in ouessant sheep. In an effort to understand and explore colour inheritance in Ouessant sheep. I needed to start from a known base in colour genetics. Unfortunately despite a lot of work done on colour inheritance in other breeds there has been virtually nothing written on Ouessant Sheep, that I have found anyway. I know that there is a current project with a french geneticist underway however if as a breeder I am to understand and breed for certain colour/pattern traits I must understand not only the general principals but also the genetics of my sheep. I await the results of a survey on ouessant sheep from the french geneticist due later this year but until then this is a little of where I am starting from.

Edit Ivo's online pedigree

IVO is a pretty average looking black ouessant sheep, or is he............. He is infact as far as his colour genetics go pretty much a known quantity because both his parents were white. He is a self black ( recessive) ram If I follow what is already written on colour inheritance in other sheep then we can assume he also has the gene for spotting.
His colour genotype as far as I can determine is AaAa BBB_ SsSs E+E+ I can fill in all but one of the blanks on his colour genotype. I am also getting to grips with the intracacies of horns and their inheritance in Ouessants which gives an added factor when considering who gets to play with whom when its time to mate.

I have speculated that it is not possible to rule out the prescence of Ed in Ouessants and so decided to start with a known recessive in order to start my breeding programme. This year I have proposed several matings all the ewes phenotypes are black some exhibit spotting and some don't. The prescence or not of Ed plays a part in being able to predict the genotype and resultant offspring of black sheep. As black is generally considered a recessive colour it is more usual to find a mix other colour combinations within a population of dark coloured sheep rather than a whole population of self coloured blacks particularly as they are though to be part of the northern european short tailed group of sheep which come in a variety of colours, recognised to go back into the mists of time and not just a recent introduction. Except of course where people have specifically bred for black or coloured sheep. I am not convinced that the islanders of Ouessant thought that much of little black sheep as to breed exclusively for black sheep.

It remains to be seen if the results allow any positive conclusions to be drawn or not. I'll keep you posted! I expect all black lambs some with and some without spotting. The spotting is likely to be limited to just the poll and or forehead. The resultant offspring should all be either heterozygous for Ed or possibly homozygous E+. I would love for a white to appear in there somewhere but we'll see.

I will also post later on the two other colour / pattern breeding trials that I have decided to run this year in order to try to understand better about colour inheritance and in particular how it is demonstrated in Ouessant Sheep.