Cow Ranchu is a variant of the transparent scale ranchu that has black and white color. Sometimes the black pattern can expand. The black comes in large patterns and small dots. Red color might be present in small areas of the body. If the red is too much, it cannot be called cow ranchu anymore. I do not know if it is the International standard name of not, but we Indonesian calls it Cow Ranchu since it resembles the color of black and white cow. This breed was rare before (especially in Indonesia), but it is available recently through imports from Fuzhou, China (if my information is correct). How people come up with this pattern is still a mystery for me. A breeder friend told me once that when he bred them, he got a variety of transparent color ranchu including calicos. So, in his view, the cow is just the offspring of the usual calico which then being separated purposely based on the color. So, it will not breed true. I doubt this explanation. In my understanding, the usual calico does not have the ability to expand its black pigment like this cow ranchu. And the black in calico usually comes in dots, not large patterns or blocks as in this cow ranchu. So, I decided to buy some cows at the end of 2019 with three purposes: first, to breed them to see if they breed true, second, to observe the expansion of the black pigment, and third, to cross them with other colors to see what will happen. Well, the 1st and 2nd purposes was facing hindrances. My first attempt to breed them resulted in so few offsprings. I think I need to breed more of them. And then, three out of five that I bought died, sadly. Gladly, I managed to crossbreed them with the common calico and with the blue metallic scale ranchu. This writing will mainly talk about the crossbreeding result.
These are the five I bought (I show them the left and right side for each):
The first three are the males. And the last two are the females. My favorites are number three and four. Too bad, they are gone. The remaining two are number one and five. I am trying to buy some more to replace them.
Their offspring in my first attempt to breed them was few, and they were weak in quality. Yet, my initial conclusion is that they breed true. Majority of the offsprings were cow ranchu. Few had minor red stains. No calico observed. Yet, I need to confirm this with my next breeding. I could not stand the quality of the offspring, so I culled most of them. I come out with these two left:
The first one has a yellowish stain in the area of its left pectoral fin. The rest are white with black pigment under the skin. The first one also has an outer black pigmen in its pectoral fin. I think they are good specimen to observe whether the black pigment will expand or not. These two are the reason for my initial conclusion that they can breed true.
Next, I mated the cows with these calicos:
I bought them from an importir friend who acquired the parents from China. So far, he has bred them true. I saw myself the offspring in his pond was pretty much similar in color characteristic. I asked for one female and two males. Too bad, he mistakenly sent me all females. Anyway, I could still pair them with my cows.
Here are the results of the cross between the calicos (female) and the cow (male) – after hard culling, ten of them remain:
The quality is far below my standar, so I cull them hard. Even these ten will be culled again after they serve the illustration purpose. (Mostly, my wife’s pupils will adopt them.) The offsprings resulted in different eye type, and different color variation: tiger, calico, sakura, and cow (the last one). I kept the cow one to see the progress of the black pigment.
I also use this blue metallic ranchu which comes from my own previous project to breed with the cows:
And the result of the cross between the blue metallic (female) and the cows are:

The offspring consists of blue metallic scales and grey metallic scales, but I want to focus on the transparent scale offspring. After much culling due to the low quality, I keep these to represent the range of transparent color emerged from this cross: tiger, calico, and kirin-like ranchu (the last one). Kirin is another variation of transparent color where the dark color and the light color seemed to separate in half. The dark color (purple, blue, grey, black) always dominates the upper part of the body, while the light color (white, yellow, red, orange) is more in the lower part. Actually, a more accurate description I think is that the light color is all over the body in the background, while the dark color exists in the foreground and occupies only the upper part of the body. The dark color usually looks with scales, or looks like a net, while the light color is transparent. Some shiny and big metallic scales are usually seen scattered all over the body.
Comparing the two crossing, it is obvious that there are overlaps: the tiger, calico, and sakura (perhaps some of the calico will turn into sakura when they lost their black pigment, or it will never happen in this cross, I do not know and do not focus on that). But interestingly, the cross between the cow and the calico produces cow-like offspring, where the other cross does not. And the cross between the cow and the blue metallic produces the kirin-like offspring, where the other cross does not. It is a hint, I think, that kirin pattern involves the blue metallic scale in the making. I kept the kirin-like one to see or use in further project.
That’s all that I can report so far. Thank you for reading. Enjoy!