Teresa Hawkin and her partner, Victor Wilton, bought their first alpacas in 2007 and now run Rosecraddoc Alpacas in Cornwall.
We have all had those “surprises” in our fields at birthing time and been left scratching our heads and muttering “where did that colour come from”? And some of us are passionate about a particular colour of alpaca be it brown, black or grey and so want to maximize the number of cria that are born this colour. A basic model of colour genetics can explain the little surprises and help us plan our coloured breeding programmes.
The Basic Theory
Don’t panic, I promise not to bang on about chromosomes, alleles and all manner of other technical terms that will make your eyes glaze over. There are just two basic facts that we need to know and understand:
- Genes, like jeans, come in pairs (never did quite understand that one – I know they have 2 legs but jumpers have 2 arms! So, every alpaca carries 2 colour genes – it receives one from each parent (these may be two of the same colour or two different colours).
- Lighter colours are dominant over darker colours. This doesn’t mean that if you mate a white animal to a fawn animal you will always get a white – it’s not quite as straightforward as that I’m afraid. What it means is that an animal will always physically appear the lighter of the two colour genes that it is carrying.
If we think about this for a moment, these two facts together tell us that for any alpaca in front of us, we know it must be carrying one gene that is the colour the animal appears plus one that is either the same or a darker colour that is “hidden” (or “masked” by the lighter, dominant colour). So for example, an alpaca that appears white must be carrying a white colour gene, but it’s second colour gene could be white, fawn, brown or black. A fawn alpaca must be carrying a fawn gene and the other gene could be fawn, brown or black (it can’t be white which is a lighter, more dominant colour or it would appear white). For a brown animal it must be carrying brown and its second colour could be brown or black. Black animals are the most straightforward of all – they must be black and black.
Identifying this second colour in your animals is the absolute key to predicting your possible mating outcomes and helping you avoid those surprises or breed for specific colours
Identifying this second colour in your animals is the absolute key to predicting your possible mating outcomes and helping you avoid those surprises or breed for specific colours. However, it sometimes takes a little detective work to do this! Herdbook is your best friend here!!! You can start by looking back through an animals pedigree and try and allocate both colour genes to each animal on there to work out what is most likely carried by the animal in question. This isn’t easy, especially once you hit an imported animal! You often end up with a couple of possibilities for an animal.
There are a couple of tricks that can help:
- If one parent is black you know for definite that any progeny will have received a black colour gene from them. So if the female in question is fawn but her sire is black then she will be carrying a fawn and a black gene.
- If the animal has a number of progeny on the ground then the quickest approximation to its second colour is to look at the progenys colours. The animal must be carrying a second colour gene that is at least as dark as its darkest progeny. So for example, if you have a fawn female and she has thrown a brown cria then she must be carrying brown or black as her second colour (because if she’d been fawn/ fawn she would have thrown a fawn colour, which is lighter than brown and the cria would have been fawn). If she has thrown a black cria, you know that she must be carrying black (remember it takes 2 black colour genes to make a black animal, one from each parent).
Be warned, you won’t be able to sit down and complete this exercise in an hour. Some will be straightforward, some will take a little work, some will take a lot and some you may not be able to map at all! I only have a small herd and still have the odd animal that is keeping me guessing! I suggest you try it out on a couple of animals to start with.
OK, so you’ve had some sort of attempt at mapping out the colour genetics of your herd (or at least an animal or two). So what now? How do you go about predicting what the outcome of any mating might be?