defect rates in fish fry

**Brhino** · 05-01-2012, 02:15 AM

I have raised some corys and some danio fry now, and a fair number of them end up with defects - spines bent in an unnatural way. Sometimes just a little, sometimes quite severely. This doesn't seem to affect their quality of life negatively but I'm wondering how often this is to be expected. What percentage of any given spawn is likely to have defects like this?

**bignellm** · 05-01-2012, 02:17 AM

Not sure, but with all the inbreeding of some fish, it's got to be higher than the norm.

My last group of Guppy fry have two grown to 1/2" now and they have bent spines. All my Molly have come out fine as have my Platy. Can't say for my swords, have only ever saved and managed to raise one up to 3/4" and it's fine. But the majority I've seen have been in Guppy.

**dmagerl** · 05-01-2012, 02:21 AM

I have a pygmy cory with only 1 eye. It looks like it was never there, the body colorations just continue through where the eye should be. Looking from the side, he sort of looks like a blind cave fish.

**Red** · 05-01-2012, 03:17 AM

If your going to breed these fish, I would say get some from one place, and some from a different place that has no correlation. It will help this problem stop.

**ScottishFish** · 05-01-2012, 09:50 AM

Are the fish you are breeding the ones from the petshop (P) or ae they the petshop offspring (F1), if it is F1xF1 breeding you are doing then there is a higher chance of mutation and defects

**Crispy** · 05-01-2012, 12:16 PM

this is why breeders prefer to pay extra for wild caught fish. as Red stated above, you should try to get your groups of fish from different sources. fish are very easily inbred and it's extremely common in the hobby.

**Sandz** · 05-01-2012, 01:38 PM

In cichlids that ive bread... Appisto's, rams, Honduran Red Points and Angels the only really noticable defect I had was in the angel fry. Fins were shorter than others, bend, cockeyed, missing an eye (could be a wound), some without fins here or there... But the fat bodied cichlids like the rams and HRP's had 0 defects.

On the danios and yellow rainbows I had a few spawns of, I noticed more of a high defect ratio... Bent spines and all that you described... IDK if egg scatterers have more of a tendancy to deform or if its the fishes body structure?

**Bigge3415** · 05-01-2012, 01:53 PM

Could be that those are more commonly found at lfs there for are farmed more. Causing more inbreeding. Thus causing a higher rate of birth defects.

**Brhino** · 05-01-2012, 02:45 PM

I'm not trying to do continuous breeding for fun or profit exactly, I just like the idea of being able to save a spawn and raise it now and then to replace any losses to the school over a long term. The consensus then is that the defects are likely due to inbreeding rather than problems with my setup?