CRS Selective Breeding question

2998 Views 26 Replies 10 Participants Last post by snausage, Dec 9, 2010

james0816

Discussion Starter · Dec 7, 2010

Just curious on the genetics and such when do selective breeding.

We'll start with my first question and genetics. In tank 2 (we'll call it tank 2 as that is SS and tank 1 is SSS), I have (4) blacks and (2) reds. The reds are both females. For the blacks, I have (2) of each.

The red females where the first to drop their little ones. One is actively dropping as of yesterday. They are in a heavily planted tank, so I can only go by what I have visually been able to see so far.

The first female has produced (again by what I have visually seen) (2) SSS, one red and one black, what looks like will be (3) SS (I think they are old enough now that I can call that one) and the remainder are S to S+. The coloration has just been outstanding for this first batch.

Of all these, the only red in the bunch is the SSS. All others are black. Which brings me to my first question of genetics as I'm curious as to why only one red one in the lot? Just seemed weird to me. I know grading is like shooting craps so I'm pretty sure you won't be able to guestimate that.

Second question. Do you find the need to call an audible from time to time between the ones you have chosen? By that I mean replacing a female with a different one or maybe even a male? I have several other SS ladies that I can swap out with. Just didn't know how long I should go to see who throws what and then decide to replace.

With the SSS, I of course don't have that luxury as yet since I only have a few to work with. They are still slow growing at their own pace and seem very contempt at the moment to take things very slow.

As for culling, and I think there is another thread that I just recently saw on this, after a couple of weeks would be a good time to remove (I can't say undesireable as they are still beautiful), the lesser grades and place them in the holding tank.

I'm sure I will come up with other questions during this project but feel free to add anything that may be helpfull.

Thx,
J.

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Darkblade48

· #2 · Dec 7, 2010

In terms of the colouration, CBS and CRS will interbreed, as they are the same species. The black variation is dominant over the red, explaining why you have more black progeny than red.

If you were to continue breeding, you would eventually lose your CRS.

To answer your second question, some people like to swap out their shrimp from time to time and/or introduce new shrimp to introduce some variation to the gene pool. Of course, with SS and SSS shrimp, the genetic variation in the shrimp is already quite little...

nilocg

· #3 · Dec 7, 2010

So if black is dominant over red, then why are there so many more reds available? I have hardly seen any blacks for sale and reds come up for sale all the time?

Darkblade48

· #4 · Dec 7, 2010

It may simply be a matter of supply and demand. Perhaps more people like Red and White over Black and White?

nilocg

· #5 · Dec 7, 2010

Thats the only thing that I could think of as well, but even the low grade CBS would have some value, you would think they would be fore sale every where?

DANIELSON

· #6 · Dec 7, 2010

I have seen the same thing with my crs/CBS tank. They are all S+ and they are kicking more reds than black at the moment. I'm going to cull my tank in a few days so I will have a better idea of what grades they are sending.

Moe

· #7 · Dec 7, 2010

I picked up 3 cbs a little over a year ago to add to my crs collection, 3 males. I have not had any cbsbabies show up yet. I have raised al least 200 crs babies since the addition of these 3 cbs.
I thought for sure I would have had some cbs show up.

Moe

· #8 · Dec 7, 2010

I picked up 3 cbs a little over a year ago to add to my crs collection, 3 males. I have not had any cbsbabies show up yet. I have raised al least 200 crs babies since the addition of these 3 cbs.
I thought for sure I would have had some cbs show up.

james0816

Discussion Starter · #9 · Dec 7, 2010

Let me pose another question on top of these.

How does everyone feel of housing CRS/CBS together? If memory serves me right, it doesn't affect the breeding line too much correct?

Vesh

· #10 · Dec 7, 2010

Darkblade48 said:
If you were to continue breeding, you would eventually lose your CRS.

For all I know about genetics I'd beg to differ. If the breeding goes equally successfully for both morphs there always will be 1/4 of CRS. And it'll be extremely difficult to get rid of CRS if desired.

Darkblade48

· #11 · Dec 8, 2010

Vesh said:
For all I know about genetics I'd beg to differ. If the breeding goes equally successfully for both morphs there always will be 1/4 of CRS. And it'll be extremely difficult to get rid of CRS if desired.

Several things about your assumptions:

1) You are assuming that colour is due to one gene.
2) You are assuming that you have a heterozygous CBS population. You would only get 1/4 CRS all the time, if (say) you continuously had a Cc x Cc occurring. This would give you your typical 25% CC, 50% Cc and 25% cc that you would get as a product of the Punnett Square. If you had a CC x CC, you would never get CRS. If you had a CC x Cc, you would never get CRS. If you had a CC x cc, you would never get CRS.

Of course, again, this can only be true if colour is due to one gene, which most likely, it is not.

james0816

Discussion Starter · #12 · Dec 8, 2010

Well the first lady only had one red in her bunch.

I'm starting to see tiny ones around from the second lady and a few of those look like they may be red. Just a tad early to tell at the moment considering how small they are.

Did find another SSS black from the first lady though. Awesome! I'll let them grow for about two more weeks before I move them out.

So how about housing reds and blacks together? How does everyone feel about that? I'm contimplating dedicating two tanks (one each) for reds and blacks in the new shrimp rack.

bsmith

· #13 · Dec 8, 2010

james0816 said:
Let me pose another question on top of these.

How does everyone feel of housing CRS/CBS together? If memory serves me right, it doesn't affect the breeding line too much correct?

Putting them together isnt an issue. Actually people think that putting CBS in the tank with CRS can enhance the white coloration as they say CBS have better white. Im not 100% sure of this because IMO anything that is white will look more white next to black instead of red.

james0816

Discussion Starter · #14 · Dec 8, 2010

Interesting and kewlness at the same time. I'll just stick with my current setup and just move them over to the new tanks as is then.

snausage

· #15 · Dec 8, 2010 (Edited)

More crs are available because the red coloration is more desirable. That's why crs tend to be more expensive than cbs.

snausage

· #16 · Dec 8, 2010

james0816 said:
Interesting and kewlness at the same time. I'll just stick with my current setup and just move them over to the new tanks as is then.

If your goal is to increase the quality of your shrimp through selective breeding, they should be separated. I actually have an SSS hino with a black head and a red bar just above the tail. I've been trying to get a good picture of it, but my crappy camera can only do so much.

To my knowledge, the only time real breeders mix cbs and crs is in conjunction with snow whites, as this is the basic formula for BKK and wine red.

nilocg

· #17 · Dec 8, 2010

snausage said:
More crs are available because the red coloration is more desirable. That's why crs tend to be more expensive than cbs.

If this is the case then where are all the cheap cbs being sold? Are people just feeding them to their fish? They still have some value, probably more so than cherry shrimp.

ShortFin

· #18 · Dec 8, 2010

I don't see where CBS is less expensive than CRS either. People are selling the same price for the same grade.

snausage

· #19 · Dec 8, 2010

nilocg said:
If this is the case then where are all the cheap cbs being sold? Are people just feeding them to their fish? They still have some value, probably more so than cherry shrimp.

To my knowledge, both crs and cbs graded as c-b are far less common than A-S grades. You have to remember that crystal shrimp haven't been widely available in the US for very long. An importer isn't going to spend a ton of money on international shipping for shrimp that are generally considered difficult to keep and have a very low profit margin.

snausage

· #20 · Dec 8, 2010

ShortFin said:
I don't see where CBS is less expensive than CRS either. People are selling the same price for the same grade.

Scroll through the invert section of aquabid. The buy it now price of crs with the same grade as cbs tends to be higher.

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