Color genes in our herd

Our herd is based on 5 mother cows:  Kruiswijk Moon EX90, PorcPrunus Noor, PorcPrunus Cleo VG89, Harron Fleur and Breoch Phlox. All are black but the first 4 have the red recessive gene. Phlox doesn’t have the red gene.

Our first herdbull was red, he was Herikehoeve Little Boy. After him all herdsires were black until in 2020 Vreugdenberg Elmo was purchased.

First Dun:

In 2014 our first dun colored calf was born. He was called PorcPrunus Karel. We were not aware he was dun and he wasn’t very special so he was steered. Looking back we know that his dam PorcPrunus Jeltje and his Sire: Mauhin Oakley (both black colored) carried the dun gene.

In 2018 our first female dun colored calf was born. Dam was Odet, (grandsire Mauhin Oakley) and the sire was a bull (PorcPrunus Hendrik) born out of a import cow (Breoch Goldies Girl). We named this calf PorcPrunus Paulet. In 2020 she gave birth to a dun heifer calf, called Willeke. (Sire: Vreugdenberg Bryan). A few weeks later PorcPrunus Daisy (black) gave birth to a dun heifer to. She’s called Erin and has the same sire as Willeke.

In 2019 we started to test our sires by UC-Davis. So now we know exactly what color genes are in our new herd sires. But the untested are given below:

 

Herdsires for the past 15 years in our herd:

Herikehoeve Little Boy RED: very possible carrier of dun gene, daughter PorcPrunus Jeltje carries dun

Mauhin Oakley: Carries dun (Dun coloured son called PorcPrunus Karel)

Stuyvenberghof Poldark: 35 progeny, none dun

Wildhof Lukas: lots of progeny, none reds none dun

PorcPrunus Farao:

PorcPrunus Horus (son of Farao): Carries red (Ed/e), no dun (tested)

PorcPrunus Hendrik: carries dun and red

Vreugdenberg Bryan: carries dun from sire (Woodmagic Hedgehog IV) no red.

Vreugdenberg Enzo: Red colored bull. doesn’t carry dun.

Tiggeloven Boris Pp: Black carries Red and dun.

In 2020 we find out that the dun coloured animals in our herd were not carriers of the normal dun on TYRP1. So we started to investigate what was happening. Carol Davidson from Canada started a research in the USA. We send hair samples for DNA testing. But the student failed. Carol passed the case over to Jessica Petersen from the Nebraska University. Many samples were lost. But we had collected hair samples from many animals that had left our farm, and of course we could collect samples from living animals.

Especially the chocolat dun coloured cows PorcPrunus Paulet, her daughter PorcPrunus Willeke and her half sister PorcPrunus Erin were tested. In 2025 the outcome of the research became public. These 3 dun coloured cows were homozygot for the gene SLC45A2 (UC-davis test with explanation). It’s an old gene that goes back to the start of the Dexter herdbooks in Ireland. In the past it can be mixed up with the TYRP1 dun colour, so no one knew there were 2 dun genes.

Were the TYRP1 gene gives more grey dun coloured Dexter, from very light grey, mousegrey till darker redish brown with liver coloured noses. This SLC45A2 gene gives chocolat brown Dexters with brown noses. We are happy we could give much input in this Dexter dun colour project!