Conundrums of Colour – Part Two

By Ross Manson

Note: Originally published in the magazine of the BCSBA March 2018, Part One was published in June 2017.

See also Conundrums of Colour – Part One

Genetics made easy? ‘Yeah right’.

At Rangiora High School, and Lincoln College we were taught about Mendel’s theory: his tall and short beans and the Hereford/Angus cross – and that was about it.

So when breeding black sheep starting in the early 1960s I bought my first black ewe and black ram. The ewe had triplets; all rams, one black, one brown and one spotted black and white. In my ignorance I kept the black one. After years of breeding only for colour I took stock and realised that I had it all wrong. Quality had to come first. I now select on a colour basis only when I have two rams of equal worth, ewes too.

In the late 1970s and early 1980s the moorit colour was discovered by Derek Weber in New Zealand. They quickly became very popular and at least one moorit was imported from Australia. As a result we all searched our flocks for moorits and while most of us didn’t find them, three of us, Charlie Tilson, Mrs Watherston and myself, found brown sheep with pale mouths. The first question we asked was ‘Were they moorits?’. None of us had actually bred any. We were told ‘No’. We just had a variation of the dominant grey sheep. However, breeding like to like proved that it was another colour, though not a moorit.

Things would have stayed where they were if I hadn’t had a talk about coloured sheep with Roger Lundie, New Zealand’s premier geneticist for coloured sheep. Talking shop with Roger is very difficult, simply because I don’t understand a lot of what he says, so I kept it simple.

Question: ‘Have we a unique colour in the brown sheep?
Answer: ‘Probably’.

Question: ‘How many colours are there in the black and coloured sheep?’
Answer: ‘Probably lots.’

That took a minute or three to think about.

Question: ‘When I breed my brown sheep together I keep getting the odd brown-violet colour – what does that mean?’
Answer: ‘Probably a recessive colour.’

That took a year or three to think about. The implications of the answers are still playing out nearly 20 years later.

What if every genetic fault or virtue is dominant and recessive? I believe they probably are.