GFP or Not GFP? How soon can you tell?

[Hollystark]

I have nine axolotl larvae/juveniles, about 1 1/2 inches long. One parent was GFP. I ordered a black light flashlight to check if any of them fluoresce but I was wondering at what point you can tell?

 

[KombatVirus]

Hey there,

When I got my axolotls they were about 2.5" long, so definitely in the juvenile stage. They were already glowing. However, GFP is a green fluorescent protein so I am assuming they should be able to glow under UV immediately from birth

 

[kaitlyn19]

You should be able to tell quite soon after birth. The earliest I have checked is 2 weeks old and the GFP was showing

 

[Margie]

Mine clearly show GFP while still in the egg.