Belly colour development in Italian alpines

Couple think I forgot to mention:
I prefer Cyclops because is small enough to be eaten by small newts larvae. Small species of Daphnia is also OK, but I realized that Cyclops have more beta carotene than Daphnia. Cyclops accumulate more beta carotene from the pray because is already concentrated in Daphnia's body.
I hope my explanations are clear despite my bad English

Thanks for all the information, Tudor. I will start to incorporate some adult Artemia and Mysis into their diet.

Interestingly, the two pics attached show the bellies of two newts that share the same tank, diet etc. One is lemon yellow, the other is a lovely rich orange (they are more different than the pictures make it seem). I don't quite understand the difference between them...any ideas?

C

Genetics do play a huge roll, you cant compare them.
Thats my assumption trough...
Cheers,

Yeah, I thought genes must be the answer...must be quite specific as these animals are siblings from sib matings.

C

If they were raised from my eggs they are definitely related. There are however different generations within the same tank. One animal could be from 5 year old parents and the other from parents that are only 1.5 years old (or a combination of the two generations). Still, genetically there won't be much variation I guess.

I still think the belly colours become more golden with age and over time you won't be able to tell the difference. That's what happened to mine anyway.

I very much doubt there is a significant genetic component, if there was, it would impact flavonoid retention as well as carotenoids and they both have plenty of flavonoids. My attempt to explain the difference would be to say that perhaps some individuals are being more succesful in accessing some types of foods than others, and because carotenoid content is so dependent on the type of food, they get a different dietary intake even though they are kept in the same conditions. In my terribly small sample i can see that two are very good at eating bloodworms while a third, smaller one, almost never gets any unless i tweezer feed it or it stumbles on a facefull of it. However, when i feed earthworm pieces, the third one is good at catching those while its two siblings pursue each other.
I´ve seen esentially the same phenomenon in my adults, where some are very good at eating some foods and others aren´t. I´ve got a female that doesn´t touch pellets, but the other four devour them with gusto. When i fed them Daphnia in the past, she was the one to show more interest and she happens to have the "reddest" belly of them all (not red at all, really, but you get my meaning).