The Accidental Smallholder Forum
Livestock => Goats => Topic started by: benkt on July 08, 2013, 11:40:48 pm
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As promised earlier, here's a picture of our two new kids. Any explanation as to why a BT billy crossed to a BS nanny ends up with black and white kids would be much appreciated!
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awwwwwwww :thumbsup:
they are too cute!
Our Daisy is due in about a week and she is saanen and the billy was black BT so I'm hoping they'll look like those but at this stage I will just be grateful for whatever she has!
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Any explanation as to why a BT billy crossed to a BS nanny ends up with black and white kids would be much appreciated!
My understanding is that the white allele is dominant. The 'BS nanny' must be a cross and has to have one copy of the BT dark allele even though she would herself still be white with the one copy of the dark recessive allele because the white allele is dominant. The kids on the other hand would have a 50% chance of inheriting a copy of the non white allele from mum and one from dad.
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They are :love: must have been a surprise if you were expecting White :D
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They are lovely. Pity she hadn't had them when I visited. My younger goat is supposedly Sanaan x Boer but her mum or grandmother once had a black kid so it must be in there somewhere. I do know some one who keeps BAs and mated on with a Sanaan. She had one black and one white kid.
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our BT x Bagots are born with REALLY dark bits, but will moult out much browner...
yours are very cute, congratulations :)
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they are lovely colours. what are your plans for them?
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The white genes are generally much stronger, so funny that they are black. We have a white kid, who is 7/8ths coloured goat (BT & BA) and yet the white colour is still dominant. They are cute! Boys/ girls?
Beth
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We've got one boy and one girl. The boy will definitely be for meat, not sure about the girl - we don't really want to keep her but as a cross breed, even from two good milking lines I'm worried their might not be a much of a market for selling her...
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The cross-breed mystery continues - vet came out to disbud today and whilst the boy had horn buds, the girl appears to be polled!
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The cross-breed mystery continues - vet came out to disbud today and whilst the boy had horn buds, the girl appears to be polled!
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If both the parents were horned/disbudded than in theory you would always get horned kids. However, if the nanny was disbudded in error - sometime the "dormant" buds under her skull can be mistaken by an inexperienced (or wanting to make sure there will definitely be no horn growth) vet for proper horn buds and s/he disbuds... that would be the most likely explanation. However there is a some anecdotal evidence that occasionally two horned parents produce polled offspring.
But I would keep checking her most days in the next few weeks to make sure she hasn't got some little horns poking through, maybe just very delayed horn growth...
And I would agree that the nanny probably has a lot of Toggenberg in her but shows white, and you may just have reached the stage of there being enough Toggenburg to switch over to Togg colour. - Much easier to keep (looking) clean!!!
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I was told that they should be disbudded at three days old b ut the person I bought Cloud from says she always waits until the horns are showing signs of appearing.
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You may just have reached the stage of there being enough Toggenburg to switch over to Togg colour.
Kind of, but more accurately in diploid organisms such as many animals are, it is often the case that one gene is dominant. But there is of course only two inherited versions of each gene (allele) within our genome. The genes that control goat coat colours are reportedly relatively simple and have several combinations. What is known as the famous "Agouti locus" present in mice and other animals is implicated. But, the white gene saanen where present is, and I quote, "completely dominant".
You could in theory have a mutant goat with a genotype of 99.9% togg but with the newly mutated white allele and it will still appear white. You could in theory also have a goat with 99.9% sannen genes with only two copies of a mutant togg like allele (although such new mutations are highly unlikely).
In this case what is likely to have happened is that in a cross bred nanny, white being dominant, always trumped the togg colour alleles until by random chance these kids ended up with two copies of togg colour alleles required.
There are a few papers out there on goat coat colour, including:
Asdell, S. A., and AD Buchanan Smith. "Inheritance of color, beard, tassels and horns in the goat." Journal of heredity 19.9 (1928): 425-430.
Hards, E. R. "The inheritance of coat characteristics in the goats of the British Isles." Brit. Goat Soc. Yearb. (1950): 67-69.
Adalsteinsson, Stefán, D. P. Sponenberg, S. Alexieva, and A. J. F. Russel. "Inheritance of goat coat colors." Journal of Heredity 85, no. 4 (1994): 267-272.