| wow, nice one.
I have gotten pretty heavy into the physiological reasons for the great color on great skin. The Jitai of the quality fish is really the type of skin associated with the type of body that we know as high quality. And like red hair and blue eyes, these phenotypic traits tend to be found with one another. If we wanted to gamble on how many red haired , blue eyed people also had freckles, if we bet over 50% we would likely be right. Yet in the great human population of the world maybe less than 10% of people have freckles.
In the case of our koi, only a percentage will have great confirmation and great shiro skin. But of the ones that do, the color will also tend to be excellent.
The physiological reason for this is that 'great skin' is thick white translucent skin but if we look under a microscope we will find that the skin is divided into defined layers of epidermis, dermis and deep dermis. The epidermis is thin and the dermis in the best fish is very thick. Color grows in both the epidermal layer and the dermis layer, and tends to ' layer on' or build ( we call it finish) as the skin expands and the fish grows. This is why Hoshi is so important as an indicator in fish that at a young age show great bone structure and great creamy white skin. It implies that beni will continue to expand deeper as the dermis gets thicker and thicker with age. The image of this is layers of color being laid down like coats paint. But in truth it is color expansion with the expansion fo the skin layers that comes with age as well as the growth of scales creating two lateral spreading layers of both epidermis and dermis on either side of the scale surface.
These great koi also possess luminescent cells within the skin layers. This reflects light back and gives that silk like effect to the skin. And concenrations of the these cells and their byproducts eventually create fukurin in the layers of skin trapped between scales.
So when we look down at the skin of a great gosanke we are seeing into the skin layers and even below the scales , into the skin layers. The color there will begin in the lower dermis and rise right up to the epidermis layer's surface.
You can envision this by imagining looking at one of those frosted glass blocks that you see used in some bathroom designs as glas block walls/windows. The clear block layed on its side doesn't allow us to read the print on the newspaper it might be sitting on. But we could certainly see into it and notice say, a rose embedded in the frosted block. Hope you get what I'm saying? JR |