Why does the color of goldfish change from black to red?

So what is the reason for this discoloration of goldfish? The ancestor of goldfish is crucian carp, which, like most other freshwater fish, has no bright colors. Moreover, under natural conditions, its body color is too bright to play the role of ecological protection color, and it will be discovered by natural enemies and difficult to survive. When the crucian carp whose body color suddenly turned red (yellow) in nature was discovered by China people, they thought it was a gift from heaven, which meant good luck. They are artificially raised and no longer compete in nature, so their bright body colors are preserved. In modern times, the adoption of cross breeding has further enriched the color of goldfish. The color of goldfish consists of melanocytes, yellow pigment cells, white reflective (guanosine) cells and blue reflective cells. When one of the cells has a high density, the fish will show this color. Different pigments have different proportions and different body colors. Multicolor goldfish consists of more than two kinds of color blocks, forming ever-changing patterns. Just like a natural palette, it uses several primary colors to produce beautiful colors.

Goldfish have charming colors and are praised by people. But you know what? Goldfish is a kind of chameleon. With the development of the body, the basic color changes gradually, and it will change several times in one's life, which often causes confusion for beginners. It is often reported in the newspaper that someone bought several black goldfish, which turned red after several months, thinking it was different. In fact, this discoloration phenomenon of goldfish was discovered long ago. In the Ming Dynasty, Li Shizhen recorded in the Compendium of Materia Medica: "Different notes: Jin Heng rushed to Lushan Mountain and saw red-scaled fish in the lake, so it was. There have been livestock since the Song Dynasty, and now people are raising people to play everywhere. Children born in late spring grass are easy to swallow and easy to metaplasia. It was black at first, but it became red after a long time. Or whitened whitebait. There are also people with changeable red, white and black spots. Its meat tastes short and hard. The feeling of things is the same: goldfish will die if they eat olive dregs and soapy water. Get the bark of poplar without lice. There is Dan fish again. That's it without trial? " Jin Shoushen, a well-known folklorist in modern times, also mentioned in his book Life in Old Beijing: "The day pearl fish compete in hue, so it can be distinguished between difficult and easy to raise because of the different colors of the fish. After being exposed to the sun, the day pearl fish are all black, and after a certain period of time, they begin to change color. There are white ones that appear first, and other colors will change color sooner or later because of changing water. If fishmongers want to pretend to be "longan fish", they will keep them in an old pond with red longan seedlings. It is rare to see the sun, but it can still be dark in three or four years. It is enough for laymen to see it. Only after the color of the day pearl fish changes can the species be identified. Its eyes, body and tail are only necessary conditions. "

Description of goldfish discoloration in Compendium of Materia Medica

So what is the reason for this discoloration of goldfish? The ancestor of goldfish is crucian carp, which, like most other freshwater fish, has no bright colors. Moreover, under natural conditions, its body color is too bright to play the role of ecological protection color, and it will be discovered by natural enemies and difficult to survive. When the crucian carp whose body color suddenly turned red (yellow) in nature was discovered by China people, they thought it was a gift from heaven, which meant good luck. They are artificially raised and no longer compete in nature, so their bright body colors are preserved. In modern times, the adoption of cross breeding has further enriched the color of goldfish. The color of goldfish consists of melanocytes, yellow pigment cells, white reflective (guanosine) cells and blue reflective cells. When one of the cells has a high density, the fish will show this color. Different pigments have different proportions and different body colors. Multicolor goldfish consists of more than two kinds of color blocks, forming ever-changing patterns. Just like a natural palette, it uses several primary colors to produce beautiful colors.

Decolorization transition crane top red individual

The body color of goldfish will change three times in its life. The first stage: discoloration in fry stage. Stage 2: Decolorization of juvenile fish. The third stage: old age fades.

The first stage: discoloration in fry stage

The newly hatched fry is transparent in color, and then gradually turns blue-gray. The discoloration of white and five-flowered goldfish began earlier, and the discoloration of young fish began one month after hatching. The discoloration period was as short as 25 days and as long as one or two months. During this period, goldfish changed from bluish gray to light white, black, light purple and flesh color, and then from light purple to deep purple, and the flesh color gradually appeared dark spots, forming the color of five flowers, black turned into white and red, and some remained unchanged, and the color gradually deepened and became black. The factors affecting the discoloration of goldfish seedlings are:

Heredity: fry are mainly affected by the genetic factors of parent fish. Excluding the influence of hybridization, fry will become the color of parent fish at the latest after 4 months. Moreover, if the parent fish changes color quickly, its offspring will change color in a short time. For farmers, the time of color change is shortened, which can save goldfish breeding time and bring it to the market earlier, thus saving costs. Choosing goldfish individuals with early discoloration as breeding fish can speed up the discoloration of this species.

Temperature: The higher the water temperature, the faster the metabolism of goldfish and the faster the discoloration process. Similarly, increasing the frequency of changing water will also stimulate the growth of goldfish. But if the water temperature is too high, it may cause the goldfish to change color too quickly. If it is not controlled in time, some species, such as red top and white top (crane top red), will lose control of the red color on their heads and continue to recede, losing the aesthetic feeling of "red (red) luck".

Illumination: The discoloration of goldfish is affected by light intensity. When the light is strong, the discoloration of goldfish will accelerate. Raising fish with clear water is beneficial to fry to receive more light, so the discoloration process is fast. But too strong light will also make the goldfish pale and affect the ornamental value.

Bait: Goldfish eat the nutrients in the bait during the fry period, which will also affect the discoloration. There are many kinds of spirulina, and the green water contains carotene, so the goldfish in the green water is more colorful. In addition, the live bait is rich in chitin, which can increase the body color of goldfish and has a similar effect.

The second stage: decoloration in infancy.

Decolorization technology of blue butterfly

Decolorization technology of blue butterfly

After the first stage of discoloration, the color of goldfish is close to that of parent fish, but the decoloration process of some multicolored goldfish has just begun. Traditionally, the first stage discoloration and the second stage decoloration of goldfish are a process. The author thinks that it takes different time to change the body color, some completely change color within 50 ~ 60 days, others take 2 ~ 3 years. Moreover, the focus of the first stage is to speed up decoloration, and the second stage is to control the decoloration process reasonably. If put together in general, it is not convenient to discuss the breeding of multicolored goldfish. For example, after some blue butterfly tails are discolored in the fry stage, some individuals continue to discolor to form black and white butterfly tails (butterfly tails of magpie flowers)-the famous goldfish variety "Panda Butterfly Tail Dizhu" is formed by continuous decoloration-twelve black butterfly tails are formed after the vertical black lines on both sides of the butterfly tail Dizhu body recede, which is also of great ornamental value, but if the black color continues to recede, the body color change will become. This decolorization process lasts for a long time, some as long as 5 to 6 years. Therefore, it is necessary to study this process independently.

In the decoloring process of multicolored goldfish varieties, individuals with special color distribution will appear. Some parts, such as mouth, eyes and fins, still keep the color before decoloration, while the fish body is white and red. This kind of goldfish is very popular in the market. It has been given attractive names: Tie Bao Jinlanchou, Peony Gaotou, Twelve Red (Black) Lion Head, Twelve Purple (Red, Black) Butterfly Tail and so on. Although these "varieties" are a transitional color, this color tone can be maintained for a long time if properly raised. Therefore, breeders should take appropriate measures not to continue decoloring, so as to prolong the body color of individuals as much as possible and keep them in the "best" state.

Optimization of parent fish: body color is most affected by heredity, and multi-color goldfish should choose parent fish with stable color. Parent fish should be at least 2 years old and keep bright colors. Don't choose goldfish with red belly mixed with black and purple, and parent fish with early decoloration of fin roots.

Slow down development: reduce the frequency of light and water change, and put goldfish indoors so that it is not directly exposed to the sun. If the indoor light is too dim, it can be supplemented manually for 2 ~ 3 hours. Feeding with old water, the goldfish's body color can be maintained for a long time because of its reduced activity and food intake, thus reducing its metabolism.

Colored feed: In recent years, the appearance of artificial colored feed for ornamental fish provides a simple and easy method for goldfish to quickly "color" and control decoloration. In production, relatively cheap carotenoids are often used as feed additives for cost reasons; Family rearing can use shrimp lycopene, which has better brightening effect.

The third stage: old age fades.

The aged five-flowered crown pearls faded into red and white varieties.

The popular iron-clad gold blue silk in the market

The red and white butterfly tails show interesting "lipstick" in the process of decoloration.

The red and white butterfly tails are decolorized into red crowned butterfly tails.

After goldfish are raised to 3 ~ 4 years old, most individuals fade and enter the fading period of old age. For example, the original black spots of Wuhua goldfish gradually receded and became red and white varieties. The black color in the body color of the top varieties of Mo Long Jingshi and Moshizi gradually receded and turned red. Even the most stable white and red have a tendency that the luster of white becomes dim and red becomes orange. However, there are also a few individuals whose fading is not obvious because of excellent varieties or proper breeding. Goldfish are easy to get sick and difficult to cure when they get old, and their life span is generally 6 ~ 7 years, so some individuals can stay the same for life. It is normal for goldfish to age and fade, but if they grow at high temperature, artificially raised or even stimulated by hormones all the year round because they do not pay attention to the control of goldfish growth during the feeding process, they will also age early. In daily feeding, the feeding amount of aged goldfish should be controlled, and the feeding amount in the growing period should be kept at around 1/2. Because the swimming of old goldfish is reduced, the feed is converted into fat accumulation, which accelerates the aging process of fish, and the color is naturally difficult to maintain.

Many scholars and practitioners have studied the discoloration of goldfish, but there are still many questions in many aspects, especially the inheritance of multicolored varieties, which is also the unique mystery of goldfish. I believe that with the attention of more people in the goldfish industry, it is not far away to master the law of discoloration and even cultivate new color varieties.