genetic help and math problem

SquashNut · #1 07/14/10, 01:32 PM

If you have a rabbit that is 50 percent of your head doe and a rabbit that is 25 percent of your head doe. And breed them together is the resulting litter still 50 percent of the head doe?
Is there a way to bring the number higher with out having the head doe any more?

#2 07/14/10, 03:09 PM

Yes, I believe the resulting litter would be 50% of your head doe. I don't think you could raise the percentage w/o breeding back to the head doe.

Devoville · #3 07/14/10, 04:19 PM

I think its more 37.5% . Sounds like a father/daughter or mother/son mating? You don't have a sibling of the head doe to use?

SquashNut · #4 07/14/10, 04:38 PM

No, i bought 1 buck/2does from 1 breeder and 1 doe from a different breeder.
I am trying to maintain some of the line of the single doe bought from the second breeder.. She got to old and so did the original buck.
I am down to 1 50 percent doe from the original buck and her. i had a 50 percent buck but he just died last night.
Then I have an assorment of 25 percent bucks and does.
For the life of me I couldn't figure out if the number would go up or stay the same.
So I would get a 37 percent kit. Is there any way to raise the number with out out crossing my line? Or is it going to just keep dropping?

arachyd · #5 07/14/10, 08:32 PM

Breed her to the 25% buck. Take the male kit with the most traits of the old doe and breed it back to the 50% doe.

Macybaby · #6 07/14/10, 08:33 PM

no - you can never get an offspring that is a higher percentage then the parent with the highest percentage. If you are careful, you could breed the two and then re breed the offspring and gradually get the percentage from 37% up to close to the 50% mark, and to the point where for practical purposes, you could say it's 50%, but you can never get higher.

The way to figure it is cut each percentage in half, and add those two together. THe 50% doe will contribute 25% and the 25% buck will contribute 12.5%. Added together you get 37.5%.

Then if you breed that back to the 50% doe you get 25% plus 18.5% (43.75).

Then back to the 50% doe and you get 25% plus 21.875%(46.875%)

And on and on - you would eventually get 49.9999%, (which most would consider 50%) but in truth, you never go get back to the full 50%.

SquashNut · #7 07/14/10, 11:26 PM

Thank you for explaining it so I can understand it.