Line Breeding

[VolunteerChin22]

Well, if you think about it, it's probably better that some animals who would be carriers or develop malo would be pelted at prime in some sense. Then those animals a) are not bred themselves and b) don't suffer the actual onset of the disease.

Let's say a pair of unknown carriers produced 100% of malo carriers or malo chins themselves but never got malo themselves and all 100% of the offspring were always pelted prior to developing the disease. In a vacuume, it could be a non issue in a pelting herd....provided you didn't put your offspring back into breeding. Of course this isn't the case.

So in some way it is "helping" to eliminate the problem but what it does not do is help you identify breeders who are carriers.

*Not saying we should advocate breeding of malo/malo carriers (purely for hypothetical thinking)*

 

[Riven]

I was thinking of what Mish said as I was reading this actually, malo will never fully disappear because of environmental issues.

I can't speak for all, but I know there are ranchers who cull malo chins and lines out, not just the one animal and mark it up to crap happens.

 

[ticklechin]

As long as chins have teeth there will be some malo, but if the genetic aspect could be removed the eviromental malo could be dealt with better, as long as there is no injury or disease enviromental malo should not happen.

 

[RDZCRanch]

As long as chins have teeth there will be some malo, but if the genetic aspect could be removed the eviromental malo could be dealt with better, as long as there is no injury or disease enviromental malo should not happen.

The problem with removing the genetic factor is that it is not a single factor. There are numerous combinations of recessive "problems" for lack of a better word that contribute to malo. To remove a recessive malady from a population is next to impossible because of the heterozygotic animals. We would need a genetic (costly) test for the specific allele(s) (need to be identified) and then after identifying ALL the carriers and malo inflicted animals they would need to be sterilized or destroyed. Considering all of our chinchillas come from the same 11 chinchillas, the amount of heterozygosity in the domestic chinchilla population is probably very high. Doing this would probably get very close to wiping out our entire domestic chinchilla population.

 

[ticklechin]

Dreams dashed, *sigh*.

 

[poetrue]

When you physically know those animals and their attributes you can isolate where the traits are coming from in the offspring specifically to what ancestor. This will assist you in taking the line breed forward and knowing what line to go back to in order to bring out the next desired trait that is still lacking in this offspring produced. Knowledge of the animal, research of the lineage, understanding of the qualities both that you can see and what you desire, strict evaluation of the offspring, and knowing what the goal you're trying to attain is what will give you the best results when line breeding.

Mark,

To the point above, when you are trying to add the next desired trait into the line - When you breed an outcross in that results in an offspring that carries that new desired trait, would you breed the offspring back to the key chinchilla that started the original line? Or would you breed the resulting offspring back to the outcross that resulted in the new desired trait to try and make it homozygous, before breeding it back to the original line?

Cheryl

 

[mark miller]

I've done both Cheryl. That's where evaluation comes in of the offspring and what it needs to improve even more. What's nice is when you get 2 females in the litter. You can take 1 back to the original line and the other to the new outcross line. This way you can evaluate which offspring continues to improve qualities. Most of the time, I just evaluate the offspring and go back to the line that has the standout quality that can still be improved further whether it be color, size, density, belly, bar, etc. For example: if I have a line bred color line and I outcross with a new line for size and the offspring gains size but loses a little color then I go back to the color line. If the offspring carries the good color but only gains a little size, then I go back to the size line to get bigger size. I evaluate the results of the line breed and the qualities that are shown and determine what needs to be improved further and then select the line to go back to for those qualities.

 

[GorillaJTA]

The problem with removing the genetic factor is that it is not a single factor. There are numerous combinations of recessive "problems" for lack of a better word that contribute to malo. To remove a recessive malady from a population is next to impossible because of the heterozygotic animals. We would need a genetic (costly) test for the specific allele(s) (need to be identified) and then after identifying ALL the carriers and malo inflicted animals they would need to be sterilized or destroyed. Considering all of our chinchillas come from the same 11 chinchillas, the amount of heterozygosity in the domestic chinchilla population is probably very high. Doing this would probably get very close to wiping out our entire domestic chinchilla population.

Not to mention random assortment which would eventually introduce genetic disease back into the population.

 

[poetrue]

I've done both Cheryl. That's where evaluation comes in of the offspring and what it needs to improve even more. What's nice is when you get 2 females in the litter. You can take 1 back to the original line and the other to the new outcross line. This way you can evaluate which offspring continues to improve qualities. Most of the time, I just evaluate the offspring and go back to the line that has the standout quality that can still be improved further whether it be color, size, density, belly, bar, etc. For example: if I have a line bred color line and I outcross with a new line for size and the offspring gains size but loses a little color then I go back to the color line. If the offspring carries the good color but only gains a little size, then I go back to the size line to get bigger size. I evaluate the results of the line breed and the qualities that are shown and determine what needs to be improved further and then select the line to go back to for those qualities.

Mark that makes perfect sense and basically what I've been doing w/my breeding in general. I think I've really learned alot from this thread and looking forward to seeing what I can do with my new found knowledge!

Cheryl