Dairy Goat Genetics

Don’t you wish you could choose a buck for a particular doe that would “fix” a trait on that doe herself? I know, right? If only it were that easy…

My daughter’s animal science textbook listed the hereditability of traits for all different types of livestock so I pulled out just the dairy goat info, and then after searching the internet to see if I could add to it, I found the same chart I just made on the ADGA website. Apparently anything over 15% is worth paying attention to and once you get above 30% you have a good chance of carefully improving your herd. But still, if you think about it, a trait that is 30% hereditable means that you should have a 15% influence from each parent. So where does the other 70% come from? It’s a mix from grandparents. So when looking at that pedigree, get to know the grandparents as it seems they contribute more than the parents do!

Time to choose a buck!

Dairy Goat Trait Heritability
Stature 52%
Strength 29%
Dairyness 24%
Rump Angle 32%
Rump Width 27%
Rear Leg Angulation 21%
Fore Udder Attachment 25%
Rear Udder Height 25%
Rear Udder Arch 19%
Medial Suspensory Ligament 33%
Udder Depth 25%
Teat Placement 36%
Teat Diameter 38%

Wiggans, G.R. and Hubbard, S.M., Genetic evaluation of yield and type traits of dairy goats in the United States.  Journal of Dairy Science 2001.                             

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Goat Eye Color

One of the fun things about Nigerians is that they can have brown or blue eyes.  Or amber. That’s not an official color, but Aspen clearly has golden eyes. Her sire has blue and it took a couple of days to be sure that hers weren’t going to be blue like his.  I’d love to know what made hers amber instead of brown.

Comon belief is that blue eyes are dominant, which means that if you pair a heterozygous blue-eyed goat with a brown-eyed goat, you have a 50% chance that each baby will have blue eyes. An interesting thing that we noticed is that Clark has brown spots in his blue, and so does his daughter, Pinecone.

If you pair two heterozygous blue-eyed goats together, you have 75% chance that each baby will have blue eyes.

And if you pair a homozygous blue-eyed goat with a brown-eyed goat, all babies will have blue eyes.

We don’t have any homozygous blue goats right now, but I might end up with some by crossing blue with blue. The only way to tell will be by breeding the blue-eyed offspring a couple times to brown-eyed goats and waiting to see if there are any brown-eyed babies.

*Note- I’ve been doing more reading after going to a show where there was another amber-eyed Nigerian, and I found a website on which the writer assumes there are four alleles for eye color instead of just two. After reading through the charts, I think this makes more sense but I can’t find anything else to back it up. The article does include the reasoning for why some blue-eyed goats have brown color mixed in (like Clark and Pinecone), how amber is a separate color (like Aspen), and how two brown-eyed parents can have blue-eyed offspring. Of course this makes things a whole lot more complicated and a lot less predictable!   http://goatspots.com/genetics/blue-eyes/