# Inbreeding warning with shrimps



## plantbrain (Dec 15, 2003)

I'm not sure how many folks have done much breeding in the past. With fish, you can get your F1's and then you need some out side stock from a different pair to bred those with. Otherwise you end up breeding cousins, brothers and sisters etc, and we know how that ends up.

Very very weak genetically. They are weak, die easily, and have a host of issues you will not be able to discern. Same with fish, livestock and people. Few keep track of the pairs and groups that breed with shrimp. They cull the nice looking ones, which is to say, they do not chose the ones that are also genetically strong. 

It's a bit easier to do with fish, but less so with shrimp.

It's still fairly easy to sell and cull the shrimp you get from the F1, and then trade, sell them off and keep some. Then trade with other folks so you increase the genetic diversity and thus the ability of the shrimp to handle a wide range of conditions.

This seems to be some of the issue with Crystal reds which are already highly inbred. So sell a a few, and get some different stock every so often.

Some folks only want all high grades, but do not want to deal with anything that also has good diverse genes so they just keep theirs they bred, rather than buying other high grades to breed with their groups.

That's understandable, but it also breeds issues into your stock and weakens them. Will folks sacrifice the shrimp's color/grades for poor health weakeness?
I've seen little evidence thus far that they have.

Some have suggested that the higher grades are much more sensitive, or I called them weaker genetically, than the lower grades where folks have little cost issue mixing new genetic stock with or care/less value.

If they are really are more sensitive, few will test them since they are worth $$$, and this provides a fairly simple reason/theory as to why they might be more sensitive vs a lower grade.

This is also something/a theory we could test as well. 
But not many will sacrifice the high grades to a wide range of environmental parameters to see, I have with the low grades and have not found any issues with NO3 up to 30ppm, PO4 up to 4 ppm, Fe at 7 mls per 80 liters daily for 2 weeks of TMG and SeaChem flourish, Temps from mid 80's down to 78F.
Not one death in several tanks, with and without plants, and breeding and fry production etc are occurring routinely.

I have to wonder why other folks have issues and kill them, I'm hardly giving them any special care. I suppose I could in buy, breed and culls the lower grades to another tank and see about high grades, I'm less interested in selling them.

Regards, 
Tom Barr


----------



## MedRed (May 20, 2008)

Inbreeding can be done correctly. The owner of my LFS is an expert on Malawi Cichlids. He has breeding colonies for peacocks that date back to the 90's. His colonies show no signs of deformities, sterilization, etc.


----------



## NeonShrimp (Mar 9, 2006)

Very interesting, thank you for sharing what you have discovered so far.

I will try seperating some of my shrimp also to make observations.


----------



## plantbrain (Dec 15, 2003)

MedRed said:


> Inbreeding can be done correctly. The owner of my LFS is an expert on Malawi Cichlids. He has breeding colonies for peacocks that date back to the 90's. His colonies show no signs of deformities, sterilization, etc.


Yes, it can be, however, most shrimp folks are not as likely to do so due to high grades value and it's much easier to pair a few rift fish than 50 shrimp.

You need to start with a good group of pairs, say 7-10 different males/females etc. then you have enough genetic stock for likely many generations, but if they are all brothers and sisters to start with, not likely.

My comments here are not about fish, but it does apply to them, it's just less of an issue and they are more aware of the genetic issues.

CRS are already highly inbred as it is, those peacocks where not and they where likely from wild healthy stock and had enough diversity to start with.

You have no idea about the shrimps is most cases.
Unless you are keeping them in certain isolated pairing/groups in separate tanks..........and you have good diversity of stock and mix them for breeding, not likely I'd say.

I know my CRS' came from 4 sources that are likely not that related.
None of them have any issues.

It might not be an issue, but why do folks claim that the high grades are more sensitive if the genes are all the same? Why are my shrimp so darn tough compared to all the claims here, on invert sites all over?

Something cannot be right here.
This sort is the more obvious lowest pick fruit with inbreeding.
Inbreeding is fine as long as it does not lead to other issues and can be done right to get certain traits you like.

I just have not seen much reasoning put into it with CRS, they just pick out the whities and sell low grades off and get the $$ for the high grades/keep.

That's not selective inbreeding.

Regards, 
Tom Barr


----------



## FrostyNYC (Nov 5, 2007)

Do you feel that inbreeding is as much an issue with less complex creatures such as shrimp as it would be with a highly complex organism such as a fish or, to give an extreme example, a human? I would think that the more simple the organism, the fewer problems that inbreeding would cause. I do agree with you, however, that it can compound undesirable recessive traits, even in shrimp. 

So assuming that you start from healthy stock, how many generations can you possibly inbreed? This isn't easy to answer, given that most people allow colony breeding in their tanks and don't know if parents are mating with children or siblings. But disregarding that, do you have any idea how often new blood should be crossed back into a colony? This sounds like a genetics thesis project.


----------



## southerndesert (Sep 9, 2007)

I have few issues with CRS and since this thread isn't about tank parameters I will not dwell there.

I have 4 tanks of CRS and one tank with CRS and Bee (same species and all are higher grade S and up to SSS) I have CRS and Bee mixed in a 20 long in an attempt to add a little diversity to my population. New blood if you will.....

I do not see CRS any harder to keep and breed than any of the other species I keep nor do the higher grades I have seem any less hardy than the others. 

I also randomly purchase GRS to mix with my current stock. Is this necessary? Heck I really don't know, but it seems a good idea and I get some really strong and bold colors in the tank housing Bee and CRS. These are also mixed into the other tanks whose populations are separated by grade somewhat.

As with all Dwarf Shrimp species clean water is the key.

Hey Tom Barr,

Really look forward to your threads and the things I have learned through some of your posts have been quite helpful, thanks.


----------



## fishsandwitch (Apr 20, 2008)

It takes about 12 generations for there to be any ill effects. But think, even if you JUST got them, they could already be inbred more than 12x. So maybe just start with 2 groups and mix it up every 3 years and you should be set.


----------



## Dwarfpufferfish (May 29, 2004)

Where did you get the 12 generation stat? I have had a colony of Cherry Shrimp that has had no new blood introduced for about 8 years. These shrimp seem no less robust than the shrimp I keep in different tanks that are always seeing new blood.

I think in breeding COULD cause problems, but I dont think it is a big a problem in Dwarf Shrimp.

I also hypothesize that when it comes to CRS that the genes linked to the desired color traits may also be linked to genes that affect strength / vigor / adaptability. I do not have proof of this, but it is certainly possible!


----------



## parkman7 (Dec 28, 2008)

I agree, inbreeding is not a big issue with lower order animals like shrimp and fish. I breed killifish, and most killi keepers breed brother sister to each other to maintain a stain. This kind of breeding is normal in nature, also it does not cause abnormalities directly. 
Very close inbreeding would be purposely breeding parent to offspring, and 2nd, 3rd generations to the first gen. People do this to select for certain traits/colors. In this case out-crossing may be necessary after a few generations.

If you simply maintain a stain by letting the group breed at random, it is normal and healthy. I always keep multiple females in my killi breeding groups, this ensures more genetic diversity even if the females are sisters.
If everyone who breeds fish/shrimp had to go catch a wild one every couple generations, there would be None in the hobby. This is simply not necessary.

Regards,


----------



## parkman7 (Dec 28, 2008)

P.S.
If you want to improve vigor and resilience, Selective breeding can achieve this in most animals. Even without out-crossing (new stock). 
The main problem with many "high grade" shrimp is that they were made higher grade by an amateur. This is mainly due to poor natural selection (remember Darwin?) The animals chosen by the breeder were chosen only for their color not for their vigor.
I think the best way is to make the water parameters less than perfect in a test aquarium, then see how many survive and breed only those. Do this with different parameters like temperature, nitrates ect. After a few generations your animals will be stronger due to natural selection (really the breeders selection).
Poor selective breeding is a far grater risk than inbreeding.

Regards


----------

