Short Carapace

[Shadow bee DK]

Some of my royal blue tigers have a short carapace. Should I remove them from my tank?  Is it genetic or can I do something to avoid it?

[jayc]

I didn't think it was genetic.

I inherited a red cherry that was similar, but it's babies look okay.

 

It seems to have improved after a moult or two in my tank.

 

I wonder if it's because Ca levels were low in it's previous tank.

Check you Ca levels with a Calcium kit.

[fishmosy]

Assuming that you mean the carapace is too short to cover down to the legs?

Theres an article on this in the most recent shrimp mag, seemed to indicate this defect was becoming more common, especially in high end shrimp. Recommended that breeders shouldn't breed them.

[jayc]

I have one where the carapace doesn't meet the abdomen.

Havent seen one whose carapace doesnt reach the legs. 

[fishmosy]

I'll try to find a pic somewhere.

[jayc]

Found it...

http://shrimpkeepersforum.com/forum/index.php/topic/3345-shrimp-deformity/

 

 

My red cherry isn't like those in the link above. 

It's got a gap between carapace and abdomen. As mentioned it seems to be getting better with each moult.

Do you think that's a genetic defect as well?

[fishmosy]

Hard to say whether its genetic i.e. Capable of being passed on to subsequent generations.

My view is - why take the risk? Cull.

[Shadow bee DK]

[fishmosy]

That looks like short skirt. Probably best to cull it.

[sushant]

A better option would be to breed such specimens in isolation, so that we can have sufficient data to prove that this condition is hereditary

[Jenbenwren]

Good point Sushant

[fishmosy]

A better option would be to breed such specimens in isolation, so that we can have sufficient data to prove that this condition is hereditary

I do not agree. Breeders in Europe, particularly Germany reccommend culling these defects, and it is logical that they do so because the traits are hereditable. They have been breeding these shrimp longer than we have in Aus. And with the limited gene pool we have in Aus, why take the risk of allowing defects to become widely established by not culling.

It is important to remember that culling to a very rigid set of traits is the only reason that we have the non-wild type varieties of shrimp that we have today.